FitSugar

Jessica Has Tickets to The Gun Show, Do You?

FitSugar — Wed, 05 Sep 2007 23:30:00 -0700

We've been watching Jessica transform into one hard body these days. Maybe it's from tugging around all that LV luggage, but I am pretty sure it has more to do with her new movie, workout regime, diet and trainer. The girl's definitely got curves; curves that I'd be willing to bet you could bounce a quarter off of. But seriously, I can't get over those arms!

So if, like me, you're totally inspired by Jessica's guns to get out and start pumping some iron, here are a few suggestions for toning up your own arms:

Push-ups. If you're new to push-ups, then stick with a basic push-up. If you're familiar with push-ups, try elevating your feet on an exercise ball.
Also, you can add the side push-up to your routine if you really want to spice it up.
Right now I am loving this Plank with Reverse Row.
Love planks? Then try the elbow and side planks.
Another great and fun workout for the arms is this boxing move.
One of my all time favorite arm exercises is the alternating hammer curl.
For a few arm moves in a row, be sure to check out the starter arms video.

So get to it ladies! With a little commitment, and healthy diet, you'll be well on your way to having arms like Jessica's. So, to see more pics of Jessica looking tone and trim, just read more

View 10 Photos ›

Bauer-Griffin

5-Factor Fitness: the Eva Mendes Story

FitSugar — Tue, 14 Nov 2006 07:30:00 -0800

It looks like Eva Mendes has jumped on the 5-Factor Fitness bandwagon and is looking great for it. According to Life and Style Weekly, she's dropped 10 - 15 pounds, she's toned, and she's changed her life style which really is the key to successful dieting. By successful I mean losing the weight and keeping it off.

Eva has joined ranks with other 5-Factor devotees and Hollywood lovelies like Halle Berry, Eve, Orlando Bloom and Benjamin Bratt. Uh huh - the 5 factors are not just for the ladies. To learn about 5-Factor read more

The 5-Factor Fitness is a fairly uncomplicated regimen of 3 meals and 2 snacks daily, consisting of: low-fat protein, fiber, healthy carbs and fats, and a sugar-free drink with every meal. The work out is an integral part of the plan to take the weight off and keep it off. But it is reasonable, combining both strength and cardio in each session of 25 minutes of daily exercise. The plan seems pretty sensible to me.

Check out books by Harley Pasternak the physiologist behind 5-Factor Fitness here. His book the 5-Factor Diet comes out on 12/26/2006.

Source

Mandy Moore and 5-Factor Fitness

FitSugar — Mon, 22 Jan 2007 10:45:17 -0800

According to Life and Style, Mandy Moore has joined the 5-Factor Fitness team, coached by diet and fitness guru Harley Pasternak. Her teammates include: Eva Mendes, Alicia Keyes, Halle Berry, Kanye West and Vanessa Williams. Zach Braff is on Pasternak's client list too, so it seems like something good that she kept from their relationship.

Want the skinny on the 5-Factor plan? Well just read more

The 5-Factor Fitness is a fairly uncomplicated regimen of 3 meals and 2 snacks daily, consisting of: low-fat protein, fiber, healthy carbs and fats, and a sugar-free drink with every meal (yep, that could be a diet soda or my beverage of choice - water). The workout is an integral part of the plan to take the weight off and keep it off. But it is reasonable, combining both strength and cardio in each session of only 25 minutes of daily exercise. The plan seems pretty doable to me, since there are occasional "cheat days" on the diet part.

Pasternak's latest book 5-Factor Diet, Hollywood's hottest eating plan, came out right after Christmas. Buy it from Amazon for $17.72, and look for a 5-Factor website coming soon too.

Cholesterol

FitSugar — Wed, 08 Oct 2008 17:34:59 -0700

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

New Guidelines for Children and Adolescents

In 2007, the American Heart Association (AHA) established new guidelines for assessing and treating high cholesterol in children and adolescents. According to the AHA’s scientific statement:

LDL (“bad") cholesterol goals for children should be 190 mg/dL or less for children without heart disease risk factors and 160 mg/dL or less for children with heart disease risk factors.
Children who are overweight or obese, as well as those with a family history of high cholesterol and heart disease, should get their cholesterol levels checked.
For overweight and obese children with cholesterol imbalances, diet changes and exercise should be tried before drug treatment. For children with cholesterol imbalances who have a family history of cholesterol and heart problems, statins are the best first-line drug therapy.

Herbs and Supplements

Garlic, whether raw or in supplement form, does not help lower LDL in patients with moderately high LDL levels, according to a 2007 Archives of Internal Medicine Study.
Policosanol, a dietary supplement derived from sugar cane, has no effect on cholesterol, indicates a 2006 Journal of the American Medical Association (JAMA) study.

Diet Plans

In a 2007 JAMA comparison study of four diet plans (Atkins, Ornish, Zone, and LEARN), the low-carbohydrate Atkins diet was best at raising HDL (“good cholesterol”) levels and lowering triglyceride levels, but did not affect LDL levels. The low-fat Ornish diet was best at lowering LDL levels.
The Mediterranean diet works better than a low-fat diet in quickly lowering cholesterol as well as blood pressure and blood sugar, suggests a 2006 Annals of Internal Medicine study.

Drug Research

In contrast to research findings released last year, rosuvastatin (Crestor) does not appear to reverse heart disease, according to a 2007 JAMA study. However, the statin drug did help slow the progression of arterial thickening.

Introduction

Lipids are the building blocks of the fats and fatty substances found in animals and plants. They are microscopic layered spheres of oil, which, in animals, are composed mainly of cholesterol, triglycerides, proteins (called lipoproteins), and phospholipids (molecules made up of phosphoric acid, fatty acids, and nitrogen). Lipids do not dissolve in water and are stored in the body to serve as sources of energy.

Cholesterol is a white, powdery substance that is found in all animal cells and in animal-based foods (not in plants). In spite of its bad press, cholesterol is an essential nutrient necessary for many functions, including:

Repairing cell membranes
Manufacturing vitamin D on the skin's surface
Producing hormones, such as estrogen and testosterone
Possibly helping cell connections in the brain that are important for learning and memory

Regardless of these benefits, when cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol. Although the body acquires some cholesterol through diet, about two-thirds is manufactured in the liver, its production stimulated by saturated fat. Saturated fats are found in animal products, meat, and dairy products.

Saturated fats are found predominantly in animal products, such as meat and dairy products, and are strongly associated with higher cholesterol levels. Tropical oils -- such as palm, coconut, and coconut butter -- are also high in saturated fats.

Triglycerides are composed of fatty acid molecules. They are the basic chemicals contained in fats in both animals and plants.

Lipoproteins are protein spheres that transport cholesterol, triglyceride, or other lipid molecules through the bloodstream. Most of the information about the effects of cholesterol and triglyceride actually concerns lipoproteins.

Lipoproteins are categorized into five types according to size and density. They can be further defined by whether they carry cholesterol or triglycerides.

Cholesterol-Carrying Lipoproteins. These are the lipoproteins commonly referred to as cholesterol.

Low density lipoproteins (LDL). (Often called the "bad" cholesterol.)
High-density lipoproteins (HDL), the smallest and most dense. (Referred to as the "good" cholesterol.)

Triglyceride-Carrying Lipoproteins.

Intermediate density lipoproteins (IDL). They tend to carry triglycerides.
Very low density lipoproteins (VLDL). These tend to carry triglycerides.
Chylomicrons (largest in size and lowest in density).

Lipoprotein(a). Lipoprotein(a), or lp(a) has a size and density somewhere between LDL and HDL. The molecules carry a protein that may interfere with the body's ability to dissolve blood clots. Lipoprotein(a) is being investigated as a possible marker or cause of heart disease.

Remnant Lipoproteins. Remnant lipoproteins are byproducts of chylomicrons, very low-density lipoproteins (VLDL), or both. Some research indicates that high levels may be an important risk factor for coronary artery disease, particularly in patients who have otherwise normal cholesterol levels.

Reducing LDL and total cholesterol levels, while at the same time boosting HDL levels, can prevent heart attacks and death in all people (with or without heart disease). Reducing LDL is the primary goal of most cholesterol therapy.

Blood tests can easily measure both HDL and overall cholesterol levels. It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated by subtracting HDL and triglyceride levels from total cholesterol. The exact formula is:

LDL = TOTAL CHOLESTEROL - HDL - TRIGLYCERIDES/5.

In 2004, the National Cholesterol Education Program updated its clinical practice guidelines. The new recommendations set lower treatment goals for LDL levels based on a patient's risk factors for heart disease.

The risk factors include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Two or more of these risk factors increases by 20% the chance of having a heart attack within 10 years.

The LDL cholesterol level is one of the most important factors in determining whether a patient needs cholesterol therapy and whether the treatment is working properly. In particular, the new guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes.


Risk Level	Goal (d/L)	OptimalGoal(d/L)
Very High Risk	70	70
High Risk	100	70
Moderate Risk	130	100
Low Risk	160	130

The following chart summarizes all goals.


Total Cholesterol Goals	LDL Goals	HDL Goals	Triglyceride Goals
Less than 200 mg/dL is desirable. Between 200 and 239 is borderline. Over 240 is high.	70 mg/dL is the new goal for very high-risk patients (recent heart attack; current active or unstable cardiovascular or cerebrovascular disease; or two multiple risk factors as defined above.) Below 100 mg/dL is optimal for everyone. It should be the goal for high-risk people including those with existing heart disease, diabetes, or two or more risk factors for heart disease; 70 mg/dL is an optimal goal for these individuals. 130 mg/dL or below for people with two or more risk factors; 100 mg/dL is an optimal goal. 160 mg/dL or below for people at less risk (one or zero risk factors); 130 mg/dL is an optimal goal. Anything above 160 is high, with levels above 190 being very high. LDL levels over 190 require medication even with no other cardiac risk factors present.	Levels above 40 mg/dL are desirable; levels above 60 mg/dL are optimal.	Below 150 mg/dL is normal. 150 - 199 is borderline high. 200 - 499 is high. Over 500 is very high.
*Risk factors for heart disease include a family history of early heart problems before age 55 for men (before age 65 for women), smoking, high blood pressure, diabetes, being older (over 45 for men and 55 for women), and having HDL levels below 35 mg/dL. People with two or more of these risk factors may have a 10-year risk of heart attack that exceeds 20%, and may therefore need to aim for LDL levels of 100 mg/dL or below.

Although current guidelines as described in the table are extremely useful, they do have pitfalls. For example, the following cholesterol levels pose some dilemmas:

Low LDL levels (protective) accompanied by low HDL, high triglycerides, or both (harmful)
High total cholesterol (harmful) accompanied by high HDL (protective)

Would individuals with these cholesterol balances be at high risk or low risk for developing heart disease? To resolve this dilemma, experts have devised a calculation for a risk ratio by dividing the total cholesterol by either total HDL or LDL. It is not clear at this point which ratio is a better predictor of heart disease, although the HDL ratio may be superior. Using this ratio, the following results indicate better to worse outlook:

The ideal ratio is 3.5 or below.
A ratio of 4.5 carries an average risk.
Ratios of 5 or higher are potentially dangerous.

For example, if a person has a high total cholesterol of 280 mg/dL but a high HDL level of 70 mg/dL, the risk ratio is 4, which actually carries a lower than average risk. The use of this ratio may predict coronary artery disease more accurately than using total cholesterol levels alone. Still, the primary goal of lipid-lowering therapy is reducing LDL levels. Evidence strongly suggests that the lower the LDL levels, the lower the risk for heart disease.

Cholesterol's Effect on the Heart

Coronary artery disease, commonly known as heart disease, is the leading cause of death in the U.S. and was responsible for nearly 500,000 deaths in 2003.

Atherosclerosis is a common disorder of the arteries. Fat, cholesterol, and other substances collect in the walls of arteries. Larger accumulations are called atheromas or plaque and can damage artery walls and block blood flow. Severely restricted blood flow in the heart muscle leads to symptoms such as chest pain.

As many as half of these deaths were probably due to unhealthy cholesterol and lipid levels. Strong evidence points to LDL as the villain and HDL as a hero in the process. The role of other lipids, notably triglycerides, is not entirely clear.

Unhealthy cholesterol, particularly low-density lipoprotein (LDL), forms a fatty substance called plaque, which builds up on the arterial walls. Smaller plaques remain soft, but older, larger plaques tend to develop fibrous caps with calcium deposits.

Click the icon to see an image of the developmental process of atherosclerosis.

The long-term result is atherosclerosis, commonly called hardening of the arteries. The heart is endangered in two ways by this process:

Eventually these calcified and inelastic arteries become narrower (a condition known as stenosis). As this process continues, blood flow slows and prevents sufficient oxygen-rich blood from reaching the heart. This condition leads to angina (chest pain) and, in severe cases, to heart attack.

Click the icon to see an image of a heart attack.

Smaller unstable plaques may rupture, triggering the formation blood clots on their surface. The blood clots block the arteries and are important causes of heart attack.

This process is accelerated and enhanced by other risk factors, including high blood pressure, smoking, obesity, diabetes, and a sedentary life style. When more than one of these risk factors is present, the risk is compounded.

The effects of cholesterol on the heart may involve more than just the arteries. There is some evidence that unhealthy levels may affect the heart muscles and increase the risk for heart failure. High cholesterol levels may even reduce the protection that aspirin provides for people with heart disease.

On an encouraging note, mortality rates associated with coronary artery disease have declined dramatically during the past 30 years. Some experts estimate that about 30% of the decline is due to better cholesterol management and statin drugs.

Studies consistently report a higher risk for death from heart disease with high total cholesterol levels (200 mg/dL and higher). The higher the cholesterol, the greater the risk. One study reported that men with total cholesterol levels higher than 240 mg/dL had a risk nearly two to four times that of men whose cholesterol was below 200 mg/dL. On average, every time a person's cholesterol level drops by a point, the risk of heart disease drops by 2%.

The primary villain in the cholesterol story is low-density lipoprotein (LDL). In a major study, the lowest incidence in heart disease was found among people with the lowest LDL levels. Lowering LDL is the primary goal of cholesterol drug and lifestyle therapy.

Low-density lipoprotein (LDL) transports about 75% of the blood's cholesterol to the body's cells. It is normally harmless. However, if it is exposed to a process called oxidation, LDL can penetrate and interact dangerously with the walls of the artery, producing a harmful inflammatory response. Oxidation is a natural process in the body that occurs from chemical combinations with unstable molecules. These molecules are known as oxygen-free radicals or oxidants.

When LDL collects on arterial walls these oxidants are released from the wall membranes.
Oxidants are missing an electron and tend to bind with other molecules in the body, a process called oxidation.
When the oxidation process modifies LDL, it signals the immune system that a harmful molecule has appeared.

Inflammation and Plaque. In response to oxidized LDL, the body releases various immune factors aimed at protecting the damaged walls. Unfortunately, in excessive quantities they cause inflammation and promote further injury to the areas they target:

White blood cells and other factors gather and form a fatty substance called plaque. (Of interest in this process is an enzyme called lipoprotein-associated phospholipase A2, which binds to oxidized LDL. Studies report that this enzyme may play a major role in the release of plaque-forming inflammatory factors.)
Other immune factors also cause inflammation and injure the endothelium, the layer of cells that line blood vessels.

Click the icon to see an image of the cut section of an artery.

Immune factors that increase the risk for blood clots are also mobilized.
Oxidized LDL plays another dangerous role by reducing levels of nitric oxide, a chemical that helps relax the blood vessels and allow blood to flow freely.

High density lipoprotein (HDL) appears to benefit the body in two ways:

It removes cholesterol from the walls of the arteries and returns it to the liver.

Click the icon to see an image of the liver.

It helps prevent oxidation of LDL. HDL actually appears to have its own antioxidant properties.

HDL helps keep arteries open and reduces the risk for heart attack. High levels of high HDL (above 60 mg/dL) may be nearly as important for the heart as low levels of LDL. HDL levels below 40 mg/dL are considered to be harmful. In one study, for each 4 mg/dL decline in HDL levels there was a 10% increase in coronary artery disease.

Triglycerides are major troublemakers for the heart. They appear to interact with HDL cholesterol in such a way that HDL levels fall as triglyceride levels rise. Low HDL is known to be harmful to the heart.

The harmful imbalance of high triglycerides with low HDL levels is also associated with obesity (particularly around the abdomen), insulin resistance, and diabetes. Insulin is a hormone essential for regulating the storage and use of glucose (sugar) and amino acids (proteins) in the body. Insulin resistance occurs when there are normal levels of insulin but the body cannot use it. Insulin resistance increases the risk for developing type 2 diabetes, and it is also associated with metabolic syndrome. Both of these conditions increase the risk for heart disease.

Some evidence also suggests that high triglycerides pose other dangers, regardless of cholesterol levels. Triglycerides, for example, may be responsible for blood clots that form and block the arteries. High triglyceride levels are also associated with the inflammatory response -- the harmful effect of an overactive immune system that can cause considerable damage to cells and tissues, including the arteries.

Studies are finding an elevated risk for angina and first heart attacks in people with elevated levels of lipoprotein(a), also known as or lp(a). This lipoprotein falls somewhere between HDL and LDL in density and may have some properties that increase the risk for blood clots. Some experts suggest, however, that high levels of lp(a) may merely be markers of late-stage atherosclerosis, not a cause. Because concentrations of lipoprotein(a) are usually inherited, they do not respond to dietary or lifestyle changes. At this time, few experts recommend drug treatments to reduce lp(a) levels. Older women, but not men, appear to be at greater risk for high lp(a) levels and their consequences.

Cholesterol's Effect on the Brain

Having adequate levels of HDL may be the most important lipid-related factor for preventing ischemic stroke, a type of stroke caused by blockage of the carotid arteries that carry blood to the brain. HDL may even reduce the risk for hemorrhagic stroke, a less common type of stroke caused by bleeding in the brain that is associated with low overall cholesterol levels.

The build-up of plaque in the internal carotid artery may lead to narrowing and irregularity of the artery's lumen, preventing proper blood flow to the brain. More commonly, as the narrowing worsens, pieces of plaque in the internal carotid artery can break free, travel to the brain, and block blood vessels that supply blood to the brain. This leads to stroke, with possible paralysis or other deficits.

The effects of high total cholesterol and LDL levels on ischemic stroke are less clear. One study suggested that the risk for ischemic stroke increases when total cholesterol is above 280 mg/dL. A 2002 study suggested that high cholesterol poses a risk for stroke only when specific proteins associated with inflammation are present.

Evidence points to high cholesterol levels, along with high blood pressure and a family history of the disease, as independent risk factors for AD. A major research target for common factors between cholesterol levels and AD has been apolipoprotein E (ApoE). ApoE plays a role in the movement and distribution of cholesterol for repairing nerve cells during development and after injury. People who carry a variant of this gene (ApoE4) are at significantly higher risk for AD.

High cholesterol may pose a risk for Alzheimer's regardless of this genetic factor, however. Some studies report that cholesterol is important within the brain for cell communication and memory.

Risk Factors

About half of all American adults have total cholesterol levels over 200 mg/dL. Over 25% have been told by doctors that they have unhealthy levels. Total cholesterol levels have been declining over the last several decades, at least among middle-aged and older adults. This decline may be partly due to the increased use of statins and other lipid-lowering medications. However, total cholesterol levels are getting higher among younger adults (ages 25 – 34 years). The major risk factor for these high rates may be the Western lifestyle. The typical high-fat/low-fiber American diet coupled with sedentary habits is largely responsible for this unfortunate trend.

Men. Heart disease is the major cause of death in men. On average, men develop coronary artery disease 10 - 15 years earlier than women do and have a greater risk for dying of heart disease at a younger age. A 2006 study suggested that high total cholesterol may also contribute to the development of high blood pressure in men.

Women. Coronary artery disease is also the number one killer of women. Women between the ages of 20 and 34, and after menopause (around age 55), have higher cholesterol levels than men. Some evidence suggests that HDL levels may be more significant in women than in men. In one study, at total cholesterol levels above 200, women with HDL levels below 50 had a higher death rate than those with levels above 50, regardless of their LDL cholesterol levels. Women also appear to be more susceptible to the high-triglyceride low-HDL syndrome, which may be a particular risk factor for heart disease.

Children and Adolescents. Children who have abnormal cholesterol levels are at increased risk of developing heart disease later in life. However, it is difficult to distinguish “normal” cholesterol levels in children. Changes in cholesterol levels occur between the ages of 8 - 18, and vary between genders and population groups. Cholesterol levels tend to naturally rise sharply until puberty, then decrease sharply, and then rise again.

In 2007, the American Heart Association established general LDL goals for children that take into account these fluctuations. The association’s LDL goals are 190 mg/dL or less for children with no additional heart disease risk factors and 160 mg/dL or less for children with additional risk factors (such as family history of high cholesterol, heart disease, and diabetes).

It is also clear that children who are overweight are at higher risk for high triglycerides and low HDL, which may be directly related to later unhealthy cholesterol levels. Studies have confirmed that childhood LDL levels and body-mass index (BMI) are strongly associated with cardiovascular risk during adulthood. The American Heart Association recommends that children who are overweight and obese, as well as those with a family history of high cholesterol, undergo cholesterol screening. Overweight and obese children who have high cholesterol should also get tested for high blood pressure, diabetes, and other conditions associated with metabolic syndrome.

As in adults, the primary source of unhealthy cholesterol levels in children comes from diets high in unhealthy fats: Saturated fats (found mainly in animal and dairy products) and trans fatty acids (found in commercial food products). Over-consumption of unhealthy fats increases the risk for both obesity and heart disease.

Less common causes of unhealthy cholesterol levels in children include:

Low-birth weight (associated with low HDL levels)
Low thyroid levels (hypothyroidism)
Kidney or liver diseases
Homozygous familial hypercholesterolemia. This is an uncommon inherited condition that causes severe cholesterol imbalances and can result in very early heart disease.
Certain medications such as specific antiseizure drugs, corticosteroids, and isotretinoin (Accutane)

Young and Middle-Aged Adults. The strongest evidence of unhealthy cholesterol levels and heart disease is in adults over age 45. However, a 2006 analysis found that while total cholesterol levels are decreasing among older adults, they are increasing in those age 25 - 34 years. Research strongly suggests that the younger a person is when unhealthy cholesterol levels develop, the greater the chance for serious heart and blood vessel problems in the future. A 2006 study in the New England Journal of Medicine indicated that keeping LDL levels low from an early age can help prevent heart disease later in life. In one important study, young men (ages 16 - 34) who had cholesterol levels at or above 240 mg/dL had two to four times the risk of dying from heart attack or other cardiac problems than did men whose cholesterol was lower than 200 mg/dL. Young men without cholesterol problems had a higher life expectancy, by up to 8 years. Other studies have suggested similar risks from unhealthy cholesterol in young women as well.

Elderly Adults. About 85% of people who die from coronary artery disease are over the age of 65. Because high cholesterol is an important risk factor for heart disease, experts strongly recommend statin or other lipid-lowering therapy for elderly people with high cholesterol levels. Surveys indicate that total cholesterol levels have been declining in older people over the last few decades. Many experts believe this is due in part to increased use of statin drugs.

In the U.S., obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, obese individuals tend to have high triglyceride levels and low HDL levels. This combination is a risk factor for heart disease. Obesity also causes other effects (high blood pressure, increase in inflammation) that pose major risks to the heart.

Obesity is a particularly hazard when it is one of the components of the metabolic syndrome, formerly known as syndrome X. This syndrome consists of obesity marked by abdominal fat, unhealthy cholesterol levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Many experts recommend that patients with metabolic syndrome should be aggressively treated with high-dose statin therapy to lower LDL levels.

Obesity is also strongly associated with type 2 diabetes, which itself poses a significant risk for high cholesterol levels and heart disease.

Low thyroid levels (hypothyroidism) are associated with unhealthy lipid levels. (Lipids are fat molecules). Specifically, people with hypothyroidism are at higher risk for high total and LDL cholesterol, triglycerides, and other lipids associated with heart disease. Treating the thyroid condition can significantly reduce cholesterol levels. Some experts suggest that patients with high cholesterol should be evaluated for thyroid function before they are given cholesterol-lowering drugs. Research is mixed on whether mild hypothyroidism (subclinical hypothyroidism) is associated with unhealthy cholesterol levels. [See In-Depth Report #38: Hypothyroidism.]

Hypothyroidism is a decreased activity of the thyroid gland which may affect all body functions. In this condition, the rate of metabolism slows, causing mental and physical sluggishness. The most severe form of hypothyroidism is myxedema, which is a medical emergency.

Genetics play a major role in determining a person's blood cholesterol levels. Children from families with a history of premature heart disease should be tested for cholesterol levels after they are 2 years old. Genes may influence whether a person has low HDL levels, high LDL levels, high triglycerides, or high levels of other lipoproteins, such as lipoprotein(a).

Some inherited disorders and genetic abnormalities have been identified:

Familial hypercholesterolemia causes dangerous increases in cholesterol. It may be more common than previously thought. One European study reported familial hypercholesterolemia in 1 out of every 400 people.
Familial lipoprotein lipase deficiency is a very rare disorder that causes depletion of lipoprotein lipase. This is an enzyme that appears to be important in the removal of lipoproteins that are rich in triglycerides. People who are deficient in it have high levels of cholesterol and fat in their blood. A very low-fat diet is essential and is an effective treatment for these individuals.
Several studies have found a genetic mutation affecting neuropeptide Y in people with high total cholesterol and LDL levels. Neuropeptide Y is a compound in the brain that regulates appetite.
Researchers have identified a gene called APOAV, which may help detect patients at risk for elevated levels of triglycerides.

Other medical conditions strongly associated with unhealthy cholesterol levels include:

Polycystic ovarian syndrome. Women with this disorder, particularly those who are obese, appear to be at increased risk for high triglyceride and low HDL levels. This risk may be due to higher levels of the male hormone testosterone in these women.

Click the icon to see an image of a polycystic ovary.

Kidney disease

Symptoms

There are no warning signs for high LDL cholesterol levels. When symptoms finally occur, they usually take the form of angina or heart attack in response to the buildup of atherosclerotic plaque in the patient's arteries. This is definitely a condition where it pays to invest in preventive medicine before dangerous complications occur.

Atherosclerosis is a disease of the arteries in which fatty material is deposited in the vessel wall, resulting in narrowing and eventual impairment of blood flow. Severely restricted blood flow in the arteries to the heart muscle leads to symptoms such as chest pain. Atherosclerosis shows no symptoms until a complication occurs.

Diagnosis

A blood test for cholesterol should include the entire lipoprotein profile: LDL, total cholesterol, HDL, and triglycerides. It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated using total cholesterol and HDL levels.

To obtain a reliable cholesterol reading, experts advise:

Avoid strenuous exercise for 24 hours before the test.
Do not eat or drink anything but water for 12 hours beforehand.
If the test results are abnormal, a second test should be performed between 1 week and 2 months after the first test.

Home Tests. Tests are available for home use and in public locations, such as shopping malls and pharmacies. For example, the CholesTrak Test can be taken at home with results in 10 minutes, but it measures only total cholesterol. The BioSafe Cholesterol Panel Test is also a home test, but it needs to be sent to a laboratory. This test, however, is very accurate and provides a full lipid profile.

Certain blood tests for factors associated with inflammation in the arteries indicate a higher risk for heart disease, even in people without unhealthy lipids:

C-reactive protein (CRP). CRP is regulated by a very potent immune factor called interleukin-6. Elevated levels have been strongly associated with the inflammatory response and a higher risk for heart attack, even in people with normal cholesterol levels. CRP is also associated with high blood pressure, insulin resistance (the primary problem in type 2 diabetes), and obesity.
A high white blood cell count.
Elevated fibrinogen (a factor responsible for blood clotting).
Lipoprotein-associated phospholipase A2 may prove to be another marker for inflammation and heart disease. Studies suggest that it may play some causal role in coronary artery disease.

A new type of test measures cholesterol levels in the skin. High skin levels may indicate an increased risk for atherosclerosis and serious heart disease.

General Screening Recommendations. Experts groups differ slightly on when screening should start, but the following are generally accepted recommendations:

Periodic cholesterol testing in all adults starting at age 20. Adults with normal cholesterol levels do not need to have the test repeated for 5 years unless changes occur in lifestyle (including weight gain and diet). Adults with risk factors for heart disease or stroke should be rechecked every 2 years.
Selective screening of children who are at risk for high cholesterol and heart disease or familial hypercholesterolemia, which is genetically elevated cholesterol. Risk factors include having parents with total cholesterol levels greater than 240, or having a parent or grandparent who had symptomatic heart disease at age 55 or younger.
Patients already being treated for high cholesterol should be checked every 2 - 6 months.

Lifestyle Changes

Although most studies that prove that lowering cholesterol saves lives are done using drug therapy, the absolute mandate for improving cholesterol levels is to first make changes in lifestyle (both diet and exercise). Even when drugs are used, healthy diet and physical activity are critical companions.

Although there are many major dietary approaches for protecting health, experts generally agree on the following recommendations for heart protection:·

Choose fiber-rich food (whole grains, legumes, nuts) as the main source of carbohydrates, along with a high intake of fresh fruits and vegetables. Walnuts in particular have cholesterol-lowering properties and are a good source of antioxidants and alpha-linolenic acid.
Avoid saturated fats (found mostly in animal products) and trans fatty acids (found in hydrogenated fats and many commercial products and fast foods). Choose unsaturated fats (particularly omega-3 fatty acids found in vegetable and fish oils).
In selecting proteins, choose soy protein, poultry, and fish over meat. A 2006 study found that soy does not help improve cholesterol. However, experts still recommend it as a heart healthy food choice.
Controlling weight, quitting smoking, and exercising are essential companions of any diet program.

After embarking on any heart healthy diet, it generally takes an average of 3 - 6 months before any noticeable reduction in cholesterol occurs. However, some people see improved levels in as few as 4 weeks. An intensive program may be necessary to achieve significant improvements in cholesterol levels and to reduce heart risk factors.

Therapeutic Lifestyle Changes (TLC) from the National Cholesterol Education Program. Guidelines from the National Cholesterol Education Program include these recommendations for preventing and managing high cholesterol levels in adults:

Choose five or more servings of fresh fruits and vegetables and six or more servings of whole grains, legumes. Soluble fiber is preferred (from cereal grains, beans, peas, legumes, and many fruits and vegetables).
Fats can be up to 35% of daily calories, but no more than 7% should be from saturated fat. (People with high triglycerides, low HDL, or both may need a higher fat intake.) Choose fats containing unsaturated fatty acids (from vegetables, fish, legumes, and nuts). Choose margarines containing sterols or stanols (Benecol, Take Control). Avoid trans fatty acids found in commercial baked products.
Protein choices should be fat-free and low-fat milk products, fish, legumes, skinless poultry, and lean meats.
Limit dietary cholesterol intake to less than 200 mg per day.
Maintain healthy body weight and a healthy level of physical fitness.

Mediterranean Diet. The Mediterranean diet is rich in heart-healthy fiber and nutrients, including omega-3 fatty acids and antioxidants. The diet consists of fruits, vegetables, and unsaturated “good” fats, particularly olive oil. Olive oil has been associated with lower blood pressure, a lower risk for heart disease, and possible benefits for people with type 2 diabetes. Olive oil also contains polyphenol, which are phytochemicals that may help boost HDL levels.

A 2006 study that compared several types of Mediterranean diets to a low-fat diet found that Mediterranean diets were better at lowering blood pressure, cholesterol levels, and blood sugar levels after only 3 months. And, in research presented at the 2007 American College of Cardiology annual conference, the Mediterranean diet proved just as good as the American Heart Association low-fat diet for preventing recurrence of heart attack, stroke, or other heart events.

There are several variations to the Mediterranean diet but general recommendations include:

Limit red meats.
Drink one or two glasses of wine each day if alcohol is enjoyable and there are no reasons to restrict its use.
Limit dairy products.
Eat moderate amounts of fish and poultry. Fish is the diet’s main protein source. Some studies suggest that fish is the primary heart-protective ingredient in this diet.
Eat plenty of fresh fruits and vegetables, nuts, legumes, beans, and whole grains.
Season with garlic, onions, and herbs. Unfortunately, garlic does not appear to help lower cholesterol, but it may have other heart benefits. [See Herbs and Supplements in this section.]

Low-Carbohydrate Diets. The Atkins, South Beach, The Zone, and other diet restrict carbohydrate intake include. A 2006 review of low-carbohydrate diets found that they did help weight loss in the short term. However, while these diets appeared to lower triglyceride and raise HDL (“good”) cholesterol levels, they also raised overall and LDL (“bad”) cholesterol levels.

In contrast, a 2007 Journal of the American Medical Association study that compared four different low-carbohydrate and low-fat diet plans (Atkins, Zone, Ornish, and LEARN) found that the Atkins diet was best at raising HDL levels and reducing triglyciderides. In terms of LDL reduction, the low-fat Ornish diet produced the best improvements while the Atkins diet had no effect on LDL. The Atkins diet did result in better moderate weight loss (an average of 10 pounds over the course of a year versus 4 - 6 pounds for the other diet plans), which in itself may have accounted for the improved heart risk factors.

Glycemic Index. Low-carb diets -- such as South Beach, The Zone, and Sugar Busters -- rely on a concept called the "glycemic index," or GI, which ranks foods by how fast and how high they cause blood sugar levels to rise. Foods on the lowest end of the index take longer to digest. Slow digestion wards off hunger pains. It also helps stabilize insulin levels. Foods high on the glycemic index include bread, white potatoes, and pasta while low-glycemic foods include whole grains, fruit, lentils, and soybeans. (These low-glycemic foods are also important components of low-fat diet plans.) A 2006 study indicated that a high-protein, low-glycemic index diet can help produce better reductions in total and LDL cholesterol than a high-protein, high-glycemic index diet. Reducing glycemic load may also help to promote weight loss, especially for women.

Low Fat Diets. Dietary guidelines recommend keeping total fat intake to 20 - 30% of total daily calories, with saturated fat less than 10% of calories. Low-fat diets generally restrict fat intake to 20% or less of total daily calories. The Ornish program, which is recommended for some heart disease patients, limits fats even more drastically. It aims at reducing saturated fats as much as possible, restricting total fat to 10%, and increasing carbohydrates to 75% of calories. In 2006, the largest study to date on low-fat diets found that they did not help prevent heart disease or cancer. Women in the study reduced their fat consumption to 24 - 29% of total daily calories. Some critics say that the study did not do enough to distinguish between good types of fats (monounsaturated omega-3 polyunsaturated) and bad fats (saturated and trans fats).

The DASH Diet. The DASH diet (Dietary Approaches to Stop Hypertension) is proven to help lower blood pressure. Results are sometimes seen within a few weeks. Restricting sodium improves results. The diet appears to have antioxidant effects and may help lower LDL cholesterol levels, although beneficial HDL levels also decline. This diet is not only rich in important nutrients and fiber but also includes foods that contain far more electrolytes, potassium (4,700 mg/day), calcium (1,250 mg/day), and magnesium (500 mg/day) than are found in the average American diet.

A diet that is effective in lowering blood pressure is called Dietary Approaches to Stop Hypertension (DASH).

The DASH diet recommends:

Limit salt intake to no more than 2,300 mg a day (a maximum intake of 1,500 mg a day is an even better goal).
Reduce saturated fat to no more than 6% of daily calories and total fat to 27% of daily calories. (But, include dairy products that are non- or low-fat. Low-fat dairy products appear to be especially beneficial for lowering systolic blood pressure).
When choosing fats, select monounsaturated oils, such as olive or canola oils.
Choose whole grains over white flour or pasta products.
Choose fresh fruits and vegetables every day. Many of these foods are rich in potassium, fiber, or both which may help lower blood pressure.
Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose modest amounts of protein (no more than 18% of total daily calories). Fish, skinless poultry, and soy products are the best protein sources.
Other daily nutrient goals in the DASH diet include limiting carbohydrates to 55% of daily calories and dietary cholesterol to 150 mg. Patients should try to get at least 30 g of daily fiber.

Slight changes to the DASH diet might help lower blood pressure even more, as well as improve cholesterol and lipid levels. Researchers reporting in the Journal of the American Medical Association and at the 2005 American Heart Association meeting said that replacing some carbohydrates in the DASH diet with more protein (from mostly plant sources) or monounsaturated fats may help reduce heart disease risk factors.

Calorie Restriction. Calorie restriction has been the cornerstone of weight-loss programs. Restricting calories in such cases also appears to have beneficial effects on cholesterol levels, including reducing LDL and triglycerides and increasing HDL levels. At this point, reducing calories and increasing exercise is still the best method for maintaining weight loss and preventing serious conditions, notably diabetes. A 2006 study reported that a low-calorie, but nutritionally balanced diet can help prevent an aging-associated change in heart function. Patients in the small study took in 1,400 - 2,000 calories a day for an average of 6 years.

The standard dietary recommendations for losing weight are the following:

As a rough rule of thumb, one pound of fat equals about 3,500 calories, so one could lose a pound a week by reducing daily caloric intake by about 500 calories a day. Naturally, the more severe the daily calorie restriction, the faster the weight loss.
To determine the daily calorie requirements for specific individuals, multiply the number of pounds of ideal weight by 12 - 15 calories. The number of calories per pound depends on gender, age, and activity levels. For instance, a 50-year-old moderately active woman who wants to maintain a weight of 135 pounds might require only 12 calories per pound (1,620 calories a day). A 25-year-old female athlete who wants to maintain the same weight might require 25 calories per pound 2,025 (calories a day).

Fat intake should be no more than 30% of total calories. Most fats should be in the form of monounsaturated fats (such as olive oil). Saturated fats (found in animal products) should be avoided.

Inactivity is one of the four major risk factors for coronary artery disease, on par with smoking, unhealthy cholesterol, and high blood pressure. In fact, studies suggest that people who change their diet in order to control cholesterol only achieve a lower risk for heart disease when they also follow a regular aerobic exercise program.

People who maintain an active lifestyle have a 45% lower risk of developing heart disease than sedentary people. Even moderate exercise reduces the risk of heart attack. One study of women found that just 1 hour of walking a week was associated with a lower risk for heart disease. The effects were similar even in women at high risk for developing heart disease.
Some studies suggest that for the greatest heart protection, it is not the duration of a single exercise session that counts but the total daily amount of energy expended. Therefore, the best way to exercise may be in multiple short bouts of intense exercise.
Burning at least 250 calories a day (the equivalent of about 45 minutes of brisk walking or 25 minutes of jogging) seems to offer the greatest protection against coronary artery disease, most likely because it raises HDL ("good cholesterol") levels. Moderate exercise has little effect on HDL.
Aerobic exercise helps to open up blood vessels and, in combination with a healthy diet, may improve blood-clotting factors.
Resistance (weight) training offers a complementary benefit to aerobics by reducing LDL ("bad cholesterol") levels.
Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina.

Cigarette smoking lowers HDL and is directly responsible for approximately 20% of all deaths from heart disease. The importance of breaking this habit cannot be emphasized enough. Once a person quits smoking, HDL cholesterol levels rise within weeks or months to levels that are equal to their nonsmoking peers. Passive smoking also reduces HDL levels in people exposed to cigarette smoke.

A number of studies have found heart protection from moderate intake of alcohol (one or two glasses a day). Moderate amounts of alcohol help raise HDL levels. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit. Pregnant women, anyone who cannot drink moderately, and people with liver disease should not drink at all.

Manufacturers of herbal remedies and dietary supplements do not need FDA approval to sell their products. Just like a drug, herbs and supplements can affect the body's chemistry, and therefore have the potential to produce side effects that may be harmful. There have been a number of reported cases of serious and even lethal side effects from herbal products. Always check with your doctor before using any herbal remedies or dietary supplements.

The following natural remedies are of interest for cholesterol control:

Garlic. Contrary to popular belief, garlic does not significantly reduce cholesterol, according to a 2007 Archives of Internal Medicine study. Researchers tested raw garlic and two types of garlic supplements in 192 patients with moderately high LDL levels. None of the forms of garlic had any effect on LDL levels. However, the researchers note that garlic may still help people with very high LDL levels and it may contain other heart-protective properties.

Policosonol. Policosanol is a nutritional supplement derived from sugar cane that has been promoted as having lipid-lowering benefits. In a randomized, placebo-controlled trial published in 2007 in the Archives of Internal Medicine, policosanol was no better than placebo in reducing LDL levels.

Treatment

In 2004, the National Cholesterol Education Program issued its latest recommendations for cholesterol control and management. These guidelines increase the number of Americans who should be taking LDL-lowering medication.

Starting Medications. Even modest lowering of high cholesterol levels, whether through drug therapy or lifestyle changes, reduces the risk of disability and death from heart disease. Most experts now focus on lowering LDL ("bad") cholesterol. Reducing LDL levels is particularly critical for patients with diabetes.

The doctor will start or consider medication when:

LDL cholesterol is 190 mg/dL or higher.
LDL cholesterol is 160 mg/dL or higher AND patient has one risk factor for heart disease.
LDL cholesterol is 130 mg/dL or higher AND patient has either diabetes or two other risk factors for heart disease.
LDL cholesterol is 100 mg/dL or higher AND patient has heart disease. (If patient has diabetes, even without heart disease, medication may be considered for an LDL cholesterol of 100 mg/dL.)
LDL cholesterol is greater than 70 mg/dL AND patient has had a recent heart attack or has known heart disease along with diabetes, current cigarette smoking, poorly controlled high blood pressure, or the metabolic syndrome (high triglycerides, low HDL, and obesity).

Risk factors for heart disease include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides)

Recent studies have found that aggressive lipid lowering with high-dose statin therapy is more beneficial than standard statin therapy in patients with existing heart disease. The Pravastatin or Atorvastatin Evaluation and Infection Trial (PROVE-IT) and the Reversal of Atherosclerosis with Aggressive Lipid-Lowering trial (REVERSAL) compared the benefits of standard statin therapy (pravastatin, 40 mg) with intensive statin therapy (atorvastatin, 80 mg) in treating patients with heart disease.

Results from PROVE-IT demonstrated that for high-risk patients, intensive statin therapy is more effective than standard therapy in lowering LDL cholesterol and C-reactive protein (CRP) levels, and that CRP levels predict risk even when LDL cholesterol has been lowered substantially. The REVERSAL data suggest that intensive statin therapy produces greater reductions in LDL and CRP levels, and that the more that statins can lower LDL, the more effective they are in reducing the progression of atherosclerosis.

An important 2006 study found that aggressive treatment with rosuvastatin (Crestor):

Helped lower LDL to below guideline levels
Moderately increased HDL levels
Reduced fatty plaque in the arteries

Experts hoped that these results suggested that statin therapy might have the potential to reverse coronary atherosclerosis. However, a follow-up 2007 study of rosuvastatin indicated that while the drug slowed the rate of atherosclerotic progression, it did not reverse heart disease. Future studies will continue to investigate this issue and to explore whether other statins have a similar positive effect on coronary artery disease. Rosuvastatin lowers LDL more than other statins, but it also carries greater risks for more serious side effects (see Adverse Effects section). Many experts believe that the more that LDL is reduced through statin therapy, the greater the reduction in risk for heart disease, heart attack, and stroke.

It is important to emphasize that cholesterol-lowering medications are used along with healthy lifestyle habits, not in place of them.

Choosing the Correct Lipid-Lowering Medication. Experts now recommend that drug treatments be tailored for raising or lowering specific lipids, depending on the patient's blood lipid picture:

Statins are now the standard drugs for most people who require LDL-lowering therapy. Bile-acid binding resins or niacin may be considered. If LDL goals are not achieved, combinations of a statin with a bile-acid resin or niacin should be considered.
Fibrates or niacin are beneficial for people who need to lower triglycerides and increase HDL.

Considerations for Children and Adolescents. In 2007, the American Heart Association (AHA) issued a scientific statement addressing the use of cholesterol drugs in children and adolescents. The AHA recommends that for children who are overweight or obese, lifestyle modifications (diet, exercise) are preferred over drug therapy and should be the first step in lowering cholesterol.

For children and adolescents who have high-risk cholesterol imbalances -- and have a family history of high cholesterol, heart attack, stroke, and diabetes -- the AHA now recommends statins as the first-line drug therapy.

Considerations for People with Diabetes. At this time, statins are recommended as the best drugs for improving cholesterol and lipid levels in people with diabetes. Studies suggest that they can reduce the risk for adverse heart events in people with diabetes, even if their cholesterol levels are normal or if their diabetes is mild. Furthermore, in one study, a statin was shown to reduce the risk of developing diabetes by 30% in people with high cholesterol. Fibrates may also be useful for people with type 2 diabetes. Niacin (nicotinic acid) has the best effect on the cholesterol profile of people with diabetes but it also increases blood sugar levels. One well-controlled study, however, found that people with diabetes who used niacin had little trouble with glucose control, and some experts believe it now may be used as an alternative to or in combination with statins.


	Effect on High LDL	Effect on Low HDL	Effect on High Triglycerides	Effect on Lp(a)
Statins	Decrease (18 - 55%)	Modest increase (5 - 15%)	Decrease (7 - 30%)	No change
Nicotinic acid (Niacin)	Modest decrease (5 - 25%) In combination with statins, may convert more dangerous LDL type to less dangerous.	Increase (15 - 35%) Drugs of choice for improving HDL levels	Decrease (20 - 50%) Drug of choice for lowering triglycerides	Decrease
Fibrates	Effect varies, but in general has little effect or modest decrease (5 - 20%)	Modest increase (6 - 20%)	Decrease (20 - 50%)	No change
Bile acid-binding resins	Decrease (15 - 30%)	Very modest increase (3 - 5%)	No change	No change

Statins are the most effective drugs for the treatment of high cholesterol, and may even prove important drugs for many people at risk for heart disease who have normal cholesterol levels. Statins inhibit the liver enzyme HMG-CoA reductase, which is used in the manufacturing of cholesterol. These drugs effectively reduce the risk of major coronary events, including first and second heart attacks, in both adult women and men of any age with unhealthy cholesterol levels. Experts estimate a 25 - 30% reduction in mortality rates when patients take statins after a heart attack. (Some believe the decrease may even be greater.) These drugs may also help improve the outcome in patients with heart disease who have had angioplasty.

Important studies have reported lower rates of heart attack, stroke, and mortality rates from all causes in statin users who were at high risk for heart disease, even if they had normal or low cholesterol levels. Benefits were similar in these people regardless of gender, age, or the presence of specific heart risk factors, such as diabetes or peripheral artery disease.

Brands. Statins are currently categorized into four groups:

So-called natural statins, including lovastatin (Mevacor, generics), pravastatin (Pravachol), and simvastatin (Zocor, generics). These are the most studied statins and have proven effectiveness and good safety record.
Synthetic statins include fluvastatin (Lescol) and atorvastatin (Lipitor). Studies using atorvastatin suggest they may reduce LDL more effectively than natural statins. In 2007, Lipitor was approved for additional indications to reduce the risk of heart attacks, strokes, certain types of heart surgery, hospitalization for heart failure, and chest pain in patients with heart disease. Lipitor is also approved for children.
The newer statins include rosuvastatin (Crestor), which was approved in 2003. Trial results have suggested that rosuvastatin is more effective in improving lipid profiles than atorvastatin, simvastatin, or pravastatin. However, like all statin drugs, rosuvastatin can cause serious side effects (see the Adverse Effects section in this report). The risks may be higher for Asian patients; this population should be started on the lowest rosuvastatin dose (5 mg).
Fixed-dose combination statins, which combine two drugs in one pill, first appeared on the market in 2004. Ezetimibe/simvastatin (Vytorin) combines two cholesterol medications that work in different ways. Simvastatin blocks cholesterol production in the liver, while ezetimibe (a non-statin cholesterol medication) blocks cholesterol absorption in the digestive tract. A 2005 study found that Vytorin was more effective than atorvastatin in lowering LDL and increasing HDL levels. Amlodipine/atorvastatin (Caduet) is a dual-therapy medication that combines the antihypertensive calcium channel blocker amlodipine with atorvastatin. It is used to treat simultaneously high blood pressure and high cholesterol.

Statins are generally administered once a day, typically in the evening because most cholesterol synthesis occurs between midnight and 3 a.m. (Atorvastatin and rosuvastatin, however, can be taken in the morning.) Statins are often prescribed along with other cholesterol-lowering drugs such as bile acid-binding resins, nicotinic acid (niacin), and fibrates.

Beneficial Effects on the Heart and Circulation.

Statins are particularly effective for lowering LDL levels. They also reduce triglycerides, apparently in direct proportion to their LDL-lowering effects. Statins also raise HDL levels, but to a lesser extent than other anti-cholesterol drugs. (The newer statins appear to produce more significant increases in HDL.) Evidence now strongly suggests that statins may offer other health benefits beyond lowering cholesterol:

Statins may improve the function of the endothelium (the lining of blood vessels), thereby improving blood flow. (This benefit apparently does not extend to people with diabetes.)
Statins appear to reduce inflammation in the arteries, which is now believed to be a major factor in blood vessel injury.
Some evidence suggests that statins may help prevent blood clotting, a major factor in heart attacks.

Beneficial Effects Outside the Heart. Studies also suggest that the benefits of statins go beyond the heart. At this time, nearly all studies on the following conditions have used natural statins:

Stroke. Statins may reduce the risk for ischemic stroke in high-risk patients with a wide range of cholesterol and lipid levels. (Ischemic strokes occur from blockage in the blood vessels that lead to the brain.) In 2003, statin therapy was shown to reduce both fatal and non-fatal stroke in patients with hypertension and at least three additional cardiovascular risk factors. A 2004 study of stroke patients found that those who were receiving statin therapy at the time of their stroke had more favorable long-term outcomes than patients who were not on statin therapy, suggesting that statin therapy may provide additional benefits to patients who develop stroke.
Diabetes. Statins may have a number of effects that are helpful for patients with diabetes, and may even prevent diabetes in some people with high cholesterol. Statins, however, do not appear to have any effect on blood vessel inflexibility in diabetes, which is an important risk factor for heart disease in these patients. A major 2003 study found that statin therapy helped prevent cardiovascular events including coronary death, heart attack, stroke, and the need for revascularization therapy in patients with diabetes, even in those who did not have high cholesterol levels or established coronary disease.
High Blood Pressure. In an important 2002 study, patients with high blood pressure but normal hMG-CoA reductase or slightly high cholesterol levels had fewer heart attacks and strokes when they took the statin atorvastatin. The study was stopped so all subjects could take statins. An earlier study showed similar benefits with the statin simvastatin.
Alzheimer's Disease. A number of studies have reported a significantly lower risk for Alzheimer's disease in people who take specific statins. Some evidence suggests they may even improve mental function in people without unhealthy cholesterol levels. Statins showing the greatest promise include lovastatin (Mevacor), pravastatin (Pravachol), and atorvastatin (Lipitor.) These statins appear to reduce levels of beta-amyloid. Other statins have not been associated with a lower risk for Alzheimer's. In fact, some researchers are concerned that certain statins that cross the blood-brain barrier may actually worsen Alzheimer's in people who already have it.
Kidney Disease. Statins may prove to protect against heart disease development in patients with mild kidney disorders. According to a 2004 study, statins may also help slow the progression of existing kidney disease.
Eye Disease. Studies are investigating whether statins can help prevent macular degeneration, an age-related eye disease that can lead to blindness. Research is still preliminary, and results have been mixed.

Macular degeneration is a disease of the retina that affects the macula in the back of the eye. The macula is important for clear central vision, allowing an individual to see fine details. There are two types of macular degeneration, dry and wet. Dry macular degeneration is more common and is characterized by the thinning of the retina and drusen, small white deposits that form within the retina. The dry form of macular degeneration is usually mild. Wet macular degeneration can happen more quickly and be more serious. It occurs when vessels under the retinal layer hemorrhage and cause the retinal cells to die, creating blind spots or distorted vision in the central vision. The disease becomes increasingly common among people in each succeeding decade over 50.

Adverse Effects. The statins tend to be better tolerated than other cholesterol-lowering drugs. In many studies the side effects reported were nearly the same as those taking placebo. Side effects may include gastrointestinal discomfort, headaches, skin rashes, muscle aches, sexual dysfunction, drowsiness, dizziness, nausea, constipation, and peripheral neuropathy (numbness or tingling in the hands and feet).

The primary safety concern with statins has involved an uncommon condition called myopathy, which can cause muscle damage and in some cases, muscle and joint pain. A specific myopathy, called rhabdomyolysis, can lead to kidney failure. Reports of rhabdomyolysis prompted the recall of cerivastatin (Baycol) in 2001. The risk for myopathy/rhabdomyolysis is highest at higher doses and in older people (over 65 years), those with hyperthyroidism, and those with renal insufficiency (kidney disease). Both statins and fibrates carry a risk for myopathy. The combination of the two drugs increases this side effect. Some people who use a statin-fibrate combination withdraw from the regimen because of muscle discomfort.

In 2005, the FDA issued a public health advisory for rosuvastatin (Crestor), noting that this drug, like other statins, increased the risk for myopathy and rhabdomyolysis. The risks were greatest at the highest dose level (40 mg). The FDA advises that patients should not start therapy at this dose. In addition, the FDA reported the results of a post-marketing study that found that people of Asian heritage had twice the blood levels of the drug as Caucasians who had taken the same dose. Because of this difference in drug metabolism, the FDA advises that Asian Americans should start treatment at the lowest rosuvastatin dose (5 mg). In general, all statin therapy should start at a lower dose and be raised incrementally until healthy cholesterol levels are maintained. Patients should immediately tell their doctor about any unusual muscle discomfort or weakness, fever, nausea or vomiting, or darkening of urine color.

Statins can also affect the liver, particularly at higher doses, so patients should have periodic liver function tests. Statins should not be taken by anyone with liver problems or by women during pregnancy or breast-feeding. Similarly, high statin doses increase the risk for kidney failure, particularly for patients with other existing risk factors (diabetes, hypertension, atherosclerosis, history of heart failure).

Interactions with Drugs and Food. Statins may have some adverse interactions with other drugs, including other cholesterol-lowering medications. Among the drugs that increase the risk for adverse effects are cyclosporine, macrolide antibiotics, and certain antifungals. Patients should tell their doctors about any other medications they are taking. Grapefruit juice and Seville oranges may increase statin potency.

Brands. Nicotinic acid is the active compound found in niacin, or vitamin B3. It is the first choice for patients with low HDL levels. Brands include Niacor, Nicolar, and Slo-Niacin. An extended-release form (Niaspan), administered at bedtime, may have fewer side effects, including headaches and flushing, than rapidly-acting niacin drugs. Although niacin is available over the counter, the active form used for cholesterol is given in much higher doses and is available only by prescription. It is important to take this medication under a doctor's direction in order to ensure its safety and effectiveness.

Benefits. When used in high doses, it has the following benefits:

Raises HDL levels higher than other anti-cholesterol drugs
Reducing triglyceride levels very effectively
Lowers LDL-cholesterol and lipoprotein(a)
Costs less than other anti-cholesterol drugs

Combinations with other drugs, particularly statins, may add significant benefits.

Side Effects. Many patients do not like the side effects of the rapidly-absorbed form of nicotinic acid. About a quarter of patients who use rapid-acting forms of nicotinic acid stop taking them. The most common side effects are flushing of the face and neck, itching, headache, blurred vision, and dizziness. They usually occur between 5 minutes to hours after taking the drug and can last for minutes to, uncommonly, hours. The body does eventually become tolerant to these effects, and they generally subside.

The following may reduce flushing and itching:

Starting with low doses taken at mealtime and gradually working up to the prescribed dose.
Taking low-dose aspirin about 30 minutes before taking nicotinic acid. This may help prevent flushing.
Avoiding hot drinks.
Choosing an extended release form. (Even with this form, it is wise to gradually increase the bedtime dose over time and take a low-dose aspirin a half-hour beforehand.)

Stomach problems are common. Other side effects include dry skin and mucous membranes and darkening of the skin.

About 30% of patients who take niacin experience elevated levels in blood glucose, which can be a problem for people with diabetes. Niacin's effects on HDL and triglycerides, however, are especially suited for the lipid imbalances that are common in diabetes. And, some studies report that people with diabetes who use niacin have little trouble with blood sugar control.

Potentially Serious Complications. About 3 - 5% of people taking nicotinic acid develop liver problems, which disappear after the medication is discontinued. The extended form (Niaspan) appears to be safe for the liver, but people with chronic liver disease should not use any form of nicotinic acid. People with gout should also avoid nicotinic acid because it elevates uric acid.

Bile-acid binding resins work, as their name suggests, by binding to bile in the digestive tract. This reduces cholesterol in the following way:

Bile is made in the liver and is used as one of the body's primary manufacturing components.

Click the icon to see an image of the gallbladder.

Once the resins bind to bile in the digestive tract, the bile is excreted in feces.
As the resins eliminate bile from the body, the liver takes more cholesterol from the bloodstream in order to produce more bile.
As cholesterol is taken out of the bloodstream, LDL levels drop.

When used in combination with dietary control, LDL levels are reduced by 15 - 20%. Combinations with nicotinic acid are even more effective, with reductions of 40 - 60% observed.

Brands. The bile-acid binding resins and similar drugs include cholestyramine (Questran, Questran Light). They are commonly used in a powder that is dissolved in liquid. Colesevelam (Welchol) is available in tablet form.

Side Effects. None of these drugs poses major risks. Most, however, cause constipation, heartburn, gas, and other gastrointestinal problems, side effects that many people cannot tolerate. One study found that only half the standard dose of colestipol was needed when psyllium, (a soluble fiber supplement found in Metamucil, Fiberall, and Perdiem), was added to the drink. In addition, bloating and constipation were reduced. Colesevelam, a newer resin, appears to have significantly fewer of these side effects.

Bile-acting drugs may contribute to calcium loss and therefore increase the risk for osteoporosis. Over time, deficiencies of vitamins A, D, E, and K may occur, and vitamin supplements may be necessary.

Rarely, toxic effects on the liver have been reported. Patients with liver disorders should be monitored.

Drug Interactions. Bile-acid binding resins may also interfere with other medications, including digoxin (Lanoxin), warfarin, beta-blocker drugs, and a number of medications used to treat low blood sugar. In order to prevent drug interactions, other drugs should be taken 1 hour before or 4 - 6 hours after taking the bile acid-binding resins.

Brands. Fibrates (sometimes called fibric acid derivatives) break down the particles that make triglycerides. Gemfibrozil is the standard fibrate. It is usually taken twice a day, 30 minutes before breakfast and before the evening meal. Newer fibrates, including fenofibrate (Lofibra, Tricor, Triglide), may be more effective in lowering cholesterol than gemfibrozil.

Benefits. Most fibrates have been shown to lower the risk of heart attack. In a 2001 study, men with both low HDL and LDL levels had a slightly lower risk of stroke after taking gemfibrozil. Fibric acid derivatives, or fibrates, have the following effects on cholesterol, lipids, and other factors:

They are good choices for many patients who need to lower triglyceride levels and increase HDL but who cannot take drugs ordinarily used for these purposes, such as nicotinic acid. In one study gemfibrozil, the standard fibrate, reduced the risk for adverse heart events by 22%.
Fibrates can produce modest reductions in LDL levels, although not as effectively as statins or other drugs. LDL may actually increase in patients with very high triglycerides who take these drugs. (The newer fibrates are much more effective in lowering LDL than gemfibrozil.)
A study on bezafibrate suggested it might have anti-inflammatory effects in patients with high triglyceride levels. Inflammation in the blood vessels is now recognized as a major contributor to the process leading to heart disease. However, according to a 2004 study, patients with diabetes or impaired fasting glucose levels were less likely to benefit from bezafibrate.
A study on fenofibrate further suggested that it reduced certain clotting factors (another risk factor for heart disease) and also uric acid (a risk factor for gout). Another study, published in 2004, demonstrated that like bezafibrate, fenofibrate has significant anti-inflammatory properties in patients with high triglyceride levels.

Concerns. Fibrates do not appear to reduce mortality rates. In one study, people who took gemfibrozil had higher rates of death from other causes, including cancer. Some evidence suggests that fibrates may affect receptors involved in cancer development. However, a number of studies have found no higher incidence of cancer.

Side Effects. Side effects may include gastrointestinal discomfort, aching muscles, sensitivity to sunlight, and skin rashes. Fibrates have been known to cause gallstones, so people with gallbladder problems should not use these drugs.

Click the icon to see an image of gallstones in the gallbladder.

The drugs may cause abnormal heart rhythms and can affect the liver and kidney.

Drug Interactions. Fibrates interact with a number of drugs and substances including warfarin, some oral drugs used for diabetes, certain antibiotics, and grapefruit juice.

Ezetimibe (Zetia) blocks absorption of cholesterol that comes from food. Ezetimibe is usually prescribed alone or in combination with a statin. In 2004, the FDA approved Vytorin, which combines ezetimbe and the statin simvastatin into a single pill.

In 2006, the FDA approved the use of ezetimbe in combination with fenofibrate (Tricor) for reduction of total cholesterol and LDL in patients with mixed hyperglycemia (high LDL levels, high triglycerides, low HDL levels) whose cholesterol has not been adequately controlled through diet alone. Fenofibrate is a cholesterol drug that is used along with diet to reduce LDL and triglycerides.

CETP Inhibitors. Cholesteryl ester transfer protein (CETP) inhibitors, such as the experimental drug torcetrapib, are a new drug class that is being investigated for its effect on raising HDL ("good" cholesterol) levels while lowering LDL ("bad") cholesterol levels. Torcetrapib was the most widely studied of these drugs. However, in December 2006, the drug’s manufacturer abruptly stopped late-stage clinical trials after discovering that torcetrapib significantly increased blood pressure and risk of death.

Several studies published in 2007 in the New England Journal of Medicine revealed that while torcetrapib does greatly boost HDL levels (by 61% in one study) and lower LDL, it has no effect on arterial plaque. Scientists are trying to understand why this drug did not work. One theory is that torcetrapib may have increased the quantity of HDL, but not the quality. It is still not clear whether the failure of trocetrapib is specific to this drug or the entire CETP drug class. Given the current findings, it is also unclear whether research will continue on other CETP drugs.

Selective Estrogen-Receptor Modulators(SERMs). Selective estrogen-receptor modulators (SERMs) have been designed to produce the benefits of estrogen without its risks. They are thought to act like estrogen in some tissues but behave like estrogen blockers (antiestrogens) in others. They include tamoxifen (Nolvadex), raloxifene (Evista), and droloxifene. Any beneficial effects of the SERMs on cholesterol and the heart are still unclear. SERMs pose a risk for deep vein blood clots, which may have implications for people with heart problems. Longer studies are needed on possible risks and benefits.

Recombinant ApoA-I Milano. ApoA-I Milano is a type of HDL protein that is found in people with very low levels of HDL. A 2003 study showed that treating patients with a synthetic form of HDL, derived from ApoA-I Milano, caused a significant regression of atherosclerosis. Ongoing trials will evaluate whether this drug can prevent cardiovascular events such as heart attack or death.

Plasmapheresis and Familial Hypercholesterolemia. Plasmapheresis is a blood-filtering procedure that is used to dramatically reduce triglycerides and may also be used to remove LDL. The procedure may be beneficial for patients with severe hereditary forms of high cholesterol who do not respond to other therapies. Studies suggest, for example, that plasmapheresis is particularly useful for patients with familial hypercholesterolemia. The process takes about 3 hours. If not performed regularly, its benefits last only about 2 weeks. People using this procedure are still advised to maintain a healthy diet and continue to take any prescribed medications to control cholesterol.

Resources

www.nhlbi.nih.gov/about/ncep -- National Cholesterol Education Program
www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.acc.org -- American College of Cardiology
www.americanheart.org -- American Heart Association
www.eatright.org -- American Dietetic Association

References

Berthold HK, Unverdorben S, Degenhardt R, Bulitta M, Gouni-Berthold I. Effect of policosanol on lipid levels among patients with hypercholesterolemiaor combined hyperlipidemia: a randomized controlled trial. JAMA. 2006 May 17;295(19):2262-9.

Covas MI, Nyyssonen K, Poulsen HE, Kaikkonen J, Zunft HJ, Kiesewetter H, et al. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Ann Intern Med. 2006 Sep 5;145(5):333-41.

Crouse JR 3rd, Raichlen JS, Riley WA, Evans GW, Palmer MK, O'Leary DH, et al. Effect of rosuvastatin on progression of carotid intima-media thickness in low-risk individuals with subclinical atherosclerosis: The METEOR Trial. JAMA. 2007 Mar 25; [Epub ahead of print]

Deedwania P, Barter P, Carmena R, Fruchart JC, Grundy SM, Haffner S, et al. Reduction of low-density lipoprotein cholesterol in patients with coronary heart disease and metabolic syndrome: analysis of the Treating to New Targets study. Lancet. 2006 Sep 9;368(9539):919-28.

Estruch R, Martinez-Gonzalez MA, Corella D, Salas-Salvado J, Ruiz-Gutierrez V, Covas MI, et al. Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med. 2006 Jul 4;145(1):1-11.

Gardner CD, Kiazand A, Alhassan S, Kim S, Stafford RS, Balise RR, et al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women: the A TO Z Weight Loss Study: a randomized trial. JAMA. 2007 Mar 7;297(9):969-77.

Gardner CD, Lawson LD, Block E, Chatterjee LM, Kiazand A, Balise RR, et al. Effect of raw garlic vs commercial garlic supplements on plasma lipid concentrations in adults with moderate hypercholesterolemia: a randomized clinical trial. Arch Intern Med. 2007 Feb 26;167(4):346-53.

Jolliffe CJ, Janssen I. Distribution of lipoproteins by age and gender in adolescents. Circulation. 2006 Sep 5;114(10):1056-62. Epub 2006 Aug 28.

Kastelein JJ, van Leuven SI, Burgess L, Evans GW, Kuivenhoven JA, Barter PJ, et al. Effect of torcetrapib on carotid atherosclerosis in familial hypercholesterolemia. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

McCrindle BW, Urbina EM, Dennison BA, Jacobson MS, Steinberger J, Rocchini AP, et al. Drug therapy of high-risk lipid abnormalities in children and adolescents. A scientific statement from the American Heart Association Atherosclerosis, Hypertension, and Obesity in Youth Committee, Council of Cardiovascular Disease in the Young, With the Council on Cardiovascular Nursing. Circulation. 2007 Mar 21; [Epub ahead of print]

McMillan-Price J, Petocz P, Atkinson F, O'Neill K, Samman S, Steinbeck K, et al. Comparison of 4 diets of varying glycemic load on weight loss and cardiovascular risk reduction in overweight and obese young adults: a randomized controlled trial. Arch Intern Med. 2006 Jul 24;166(14):1466-75.

Nissen SE, Tardif JC, Nicholls SJ, Revkin JH, Shear CL, Duggan WT, et al. Effect of torcetrapib on the progression of coronary atherosclerosis. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

Review Date:
7/23/2007
Reviewed By:
Alan Greene, MD, FAAP, Chief Medical Officer, A.D.A.M., Inc.; and Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

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adam.com

Colon and rectal cancers

FitSugar — Wed, 08 Oct 2008 17:35:05 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Risk Factors
Dietary Factors
Prevention
Diagnosis
Staging
Prognosis
Surgery
Medications
Radiation Treatment
Follow-up Testing
Treatment for Metastasized ...
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approval

In September 2006, the Food and Drug Administration approved panitumumab (Vectibix) for the treatment of patients with colorectal cancer that has spread to other parts of the body following chemotherapy. Like cetuximab (Ertibux), panitumumab targets the epidermal growth factor receptor (EGFR) on cancer cells. Panitumumab is the first new colorectal cancer drug approved since 2004. The FDA granted accelerated approval to panitumumab based on a clinical trial of patients with metastatic cancer. The average time to disease progression or death was 96 days in patients treated with panitumumab compared to 60 days in patients who received standard care.

Diet and Colorectal Cancer Recurrence

Evidence indicates that diet plays a role in colorectal cancer prevention. Now, a 2007 study in the Journal of the American Medical Association (JAMA) suggests that dietary factors also affect the risk of cancer recurrence. Patients with stage III colorectal cancer who ate lots of red meat, refined grains, and sweets had a higher risk of cancer recurrence and death than patients whose diets were high in fruits and vegetables, poultry, and fish.

Folic Acid No Good for Prevention?

Many experts have long believed that folic acid supplements may help protect against colorectal cancer. But according to a 2007 JAMA study, high-dose folic acid supplements may not prevent colorectal cancer and may actually increase the risk for adenomatous polyp formation. Adenomatous polyps are benign colorectal tumors that can potentially become cancerous. In the study, patients who took folic acid supplements had a greater risk of developing new, more numerous, and larger adenomatous polyps than patients who did not take the supplements.

NSAIDS Not Recommended for Colorectal Cancer Prevention

In March 2007, the U.S. Preventive Services Task Force (USPSTF) recommended against the routine use of aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) to prevent colorectal cancer in people who are at average risk for this disease. Several recent studies have indicated that aspirin, and NSAIDs such as celecoxib (Celebrex), can help prevent colorectal cancer. But the USPSTF notes that the risks of these drugs outweigh the benefits. Long-term daily use of NSAIDs increases the risk for gastrointestinal bleeding, kidney function problems, and heart attack and stroke.

Introduction

Cancers of the colon and rectum, often referred to collectively as colorectal cancer, are life-threatening tumors that develop in the large intestine.

More than 80% of colorectal tumors evolve from adenomatous polyps. These gland-like growths develop on the mucous membrane that lines the large intestine. They are usually either:

Tubular polyps, which protrude mushroom-like
Villous adenomas, which are flat and spreading and are more apt to become malignant (cancerous)

Polyps are very common and almost always benign. Their numbers increase with age. Polyps are found in about 25% of people by age 50, and 50% of people by age 75. Fewer than 1% of polyps under 1 centimeter (slightly less than half an inch) become cancerous. About 10% of larger polyps become cancerous within 10 years, and about 25% of these larger polyps become cancerous after 20 years. Certain inherited polyps can become cancerous more rapidly.

Digestion takes place in the gastrointestinal (GI) tract, essentially a long tube that extends from the mouth to the anus. It is a complex organ system that first carries food from the mouth down the esophagus to the stomach. Food then travels through the small and large intestines before being excreted through the rectum and out the anus.

The esophagus, stomach, large and small intestine -- aided by the liver, gallbladder, and pancreas -- convert the nutritive components of food into energy and break down the non-nutritive components into waste to be excreted.

The esophagus is a narrow muscular tube, about 9 1/2 inches long that begins below the tongue and ends at the stomach.

In the stomach, acids and stomach motion break food down into particles small enough so that the small intestine can absorb nutrients.

Click the icon to see an image of stomach anatomy.

The small intestine, despite its name, is the longest part of the gastrointestinal tract, extending for about 20 feet. Food passes from the stomach through its three parts: first the duodenum, then the jejunum, and finally the ileum. Most of the digestive process occurs in the small intestine.

Click the icon to see an image of small intestine anatomy.

Undigested material, such as plant fiber, is passed next to the large intestine, mostly in liquid form. The large intestine is wider than the small intestine but only about 6 feet long. It is the final portion of the digestive tract and includes the cecum, the appendix, the colon, and the rectum, which extends to the anus.

Cecum and Appendix. The cecum and the appendix are located in the lower-right quadrant of the abdomen.

Colon. The colon absorbs excess water and salts into the blood. The remaining waste matter is converted to feces through bacterial action. The colon is divided into four major sections.

Click the icon to see an image of large intestine anatomy.

The first section, the ascending colon, extends upward from the cecum on the right side of the abdomen.
The second section, the transverse colon, crosses the upper abdomen to the left side.
The third section extends downward on the left side of the abdomen toward the pelvis and is called the descending colon.
The final section is the sigmoid colon.

Rectum and Anus. Feces are stored in the descending and sigmoid colon until they are passed through the rectum and anus. The rectum extends through the pelvis from the end of the sigmoid colon to the anus.

Causes

In most cases of colon or rectal cancers, the cause or causes are unknown. Defects in genes that normally protect against cancer play the major role in causing polyp cells to continuously spread and become cancerous. Some of these cases are caused by inherited genetic defects, and such patients usually have family histories of colorectal cancer. Most of the genetic mutations involved in colon cancers, however, appear to arise spontaneously (no strong family history) rather than being inherited. In such cases, environmental or other factors trigger genetic changes in the intestine that lead to cancer.

About 6% of cases of colon cancer are due to inherited factors.

APC Gene and Familial Adenomatous Polyposis (FAP). When the adenomatous polyposis coli (APC) gene is normal, it helps suppress tumor growth. In its defective form, it permits high levels of the protein beta-catenin to accumulate, which accelerates cell growth leading to polyps. Various genetic mutations that affect the APC gene directly or indirectly have been identified:

Familial adenomatous polyposis (FAP) is a rare and serious disorder in which the patient inherits an adenomatous polyposis coli (APC) mutation from either parent. It occurs in about 1 in 8,000 people. During early adulthood, hundreds to thousands of polyps grow in the colon. FAP causes less than 1% of all cases of colorectal cancer, but if untreated, virtually everyone who inherits this condition develops cancer before the age of 40. Many of the deaths attributed to FAP can be prevented with early and aggressive surgical treatment.
Non-inherited mutations of the APC gene have been detected in nearly all patients with spontaneous colon cancers.

Hereditary Nonpolyposis Colorectal Cancer (HNPCC). Hereditary nonpolyposis colorectal cancer (HNPCC), also known as Lynch syndrome, accounts for at least half of colorectal cancers that run in families. (However, only 3% or less of all colorectal cancers are due to this problem). About 50 - 80% of people who inherit the abnormal gene will develop colon cancer. HNPCC tends to develop in the right side of the colon, often in young individuals. (Left-sided cancers can still occur as well.)

People who inherit HNPCC and other defects are prone to other cancers, including uterine and ovarian cancers, as well as cancers of the small intestine and kidney system (very rare). HNPCC is highly associated with genes containing an abnormality called microsatellite instability (MSI), which is a sign of defective DNA repair. Testing tumors for MSI in people with newly diagnosed colon cancer who also have a family history of the disease may prove to be an effective method for identifying patients with hereditary nonpolyposis colorectal cancer. Tests are being developed that can detect the actual HNPCC genetic abnormality (mutation) that was inherited from a father or mother. The two most commonly affected genes are MSH2 and MLH1.

Cyclooxygenases and Prostaglandins. Cyclooxygenase 1 and 2 (COX-1 and COX-2) are enzymes involved in the production of prostaglandins, substances produced by the body that cause inflammation, widen and narrow blood vessels, control muscle contractions, and inhibit hormones that regulate fat metabolism. COX-2, but not COX-1, appears to play a role in the development and spread of colorectal tumors. COX-2 increases the levels of prostaglandin E2 (PGE2), which, in turn, stimulates factors that inhibit apoptosis, the natural process whereby all cells, including cancerous ones, self-destruct. It also activates interleukin-6 (IL-6), a factor in the immune system that is associated with cancer cell invasion.

C-Reactive Protein (CRP). CRP is another indicator of inflammation. In a 2004 study published in the Journal of the American Medical Association, elevated CRP levels predicted the development of colon -- but not rectal -- cancer.

Bile Acid Salts. Deoxycholic acid, which is found in the fat-digesting bile salts released by the gallbladder, appears to have carcinogenic properties. Its effects are now believed to play a role in some cases of colon cancer. Levels of the acid can rise as a result of high-fat diets or certain diseases.

Growth Factors. Chronically higher circulating levels of growth factors, including insulin-like growth factor, have been associated with colorectal cancer.

Inflammatory bowel diseases include Crohn's disease and ulcerative colitis. These chronic disorders cause persistent injuries in the intestinal tract that can, in some cases, produce cancerous changes.

Symptoms

It is possible to have colon or rectal cancer without symptoms. Many patients are free of symptoms until their tumors are quite advanced.

Weight loss and changes in bowel movements are general symptoms for colon cancer, but these symptoms also occur in many other diseases.

Blood in the stools is a common sign of many intestinal cancers. It may appear red if it is fresh or black if it is old. It should be reported to a doctor immediately, even though it is often caused by conditions other than cancer, including:

Hemorrhoids
Minor tears around the rectal or anal areas
Diverticulosis

In addition, stool can change color by:

Eating certain red foods, such as beets or red licorice (red)
Taking iron supplements and medications that have bismuth subsalicylate, most commonly Pepto-Bismol (black)

Nevertheless, blood in the stools is an abnormal finding that should never be ignored. Always report it to your doctor for further advice.

Symptoms of colorectal cancer vary widely depending on the location of the cancer within the large intestine.

Tumors in the Cecum and Ascending Colon (Right Colon). The waste matter in the first portion of the colon is in liquid or semi-liquid form. Tumors that develop here do not change bowel habits or stool formation, but they may cause intermittent or chronic bleeding. Although the stools look normal, patients may develop symptoms of anemia from iron deficiency. Such symptoms include weakness, fatigue, heart palpitations, shortness of breath, and exercise intolerance.

Tumors in the Transverse Colon. As waste material passes across the upper quadrants of the abdomen (the transverse colon), the intestine absorbs water, and the waste matter becomes more solid. In addition to bleeding, tumors here may cause cramps, gas, partial or complete obstruction, and even perforation of the bowel. Anemia can also occur.

Tumors in the Descending Colon and Rectum (Left Colon). When tumors partially block the lower intestine, thin, pencil-shaped stools may form. Bowel habits can change. Tumors in the rectum and lowest part of the intestine can cause pain and a feeling of fullness. Defecation may be painful, or patients may feel the urge to defecate but nothing happens. Bleeding from these locations may be brisk and bright red or maroon, but cancer is often detected before symptoms of chronic anemia develop.

Risk Factors

Colorectal cancer is the third most common cancer in the U.S., with Americans facing a lifetime chance of 5.5 - 6% for this cancer. In 2007, colorectal cancer was expected to cause 153,760 new cases and 52,180 deaths in the United States. About 73% of cancers occur in the colon and 27% in the rectum.

The lifetime risk of cancer of the colon or rectum is 5.9% for men and 5.5% for women.

Colorectal cancer risk increases with age. More than 90% of these cancers occur in people over age 50. The rate of colorectal cancer in patients under 20 years is less than 1 in 100,000 per year. At age 50 about 1 in 2,000 people per year will develop colorectal cancer. After age 65, this rate increases to almost 3 in 1,000.

African-Americans have the highest risk of being diagnosed with, and dying from, colorectal cancer. Among Caucasians, Jews of Eastern European (Ashkenazi) descent have an elevated rate of colorectal cancer. Asian Americans/Pacific Islanders, Hispanics/Latinos, and American Indians/Alaska Natives have a lower risk than Caucasians.

About 20 - 25% of colorectal cancers occur among people with a family history of the disease. (Seventy-five percent of cases are due to other causes.) People who have more than one first-degree relative (sibling or parent) with the disease are especially at high risk. The risk is even higher if the relative was diagnosed with colorectal cancer before the age of 60.

About 5 - 10% of patients with colorectal cancer have an inherited genetic abnormality that causes the disease. Genetic mutations associated with colorectal cancer include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer.

The risks for colon cancer are far higher in industrialized nations than less developed countries. A Western lifestyle, being sedentary, smoking, and having excess weight have all been associated with increased risk for colorectal cancer. (However, about 75% of cases occur without a known predisposing factor.)

Dietary Factors. Eating a lot of red meat increases the risk for colorectal cancer. Other types of animal protein (low-fat dairy products, fish, poultry) may decrease the risk of developing polyps and colorectal cancer. Studies on fruits, vegetables, and fiber are mixed. Some evidence suggests that diets very low in fruits and vegetables may increase the risk. In any case, eating a variety of fruits and vegetables should be part of a healthy diet.

A 2007 study in the Journal of the American Medical Association suggested that diet may play a role in colorectal cancer recurrence, as well as prevention. The study evaluated patients with stage III colon cancer who had been treated with surgery and chemotherapy. Patients who ate diets high in red and processed meats, refined grains, and sweets had a higher risk of cancer recurrence and poorer survival than patients whose diets were high in fruits and vegetables, poultry, and fish.

Alcohol and Smoking. Alcohol use and smoking increase the risk for colorectal cancer. Patients who smoke and drink may also be diagnosed with colorectal cancer at a younger age than non-drinkers and non-smokers. Several studies suggest that women who smoke are at especially high risk of developing colorectal cancer.

Obesity. There is a demonstrated link between body mass and colon cancer risk for both men and women. The Centers for Disease Control and Prevention has reported that the risk of colon cancer rises as body mass index increases. Obesity has been associated biologically with higher circulating levels of insulin and a hormone called insulin-like growth factor. Chronically high levels of these substances may increase colorectal cancer risk.

Physical Inactivity. More than 50 studies from around the world suggest that physical activity helps prevent colon cancer. In contrast, exercise does not protect against rectal cancer.

Crohn's disease and ulcerative colitis are chronic afflictions of the large intestine known as inflammatory bowel diseases (IBD). Both have been linked to increased risk for colorectal cancer. (Patients with ulcerative colitis have a higher risk than those with Crohn's disease.) Family histories are helpful in determining risk associated with inflammatory bowel disease. Some studies suggest the following:

Patients with IBD who have a family history of colorectal cancer face up to a five-fold risk of colon cancer themselves.
Individuals without IBD who have relatives who suffered from both IBD and colorectal cancer may face a higher risk for developing colorectal cancer themselves.
Individuals without IBD but with a family history of IBD and no colon cancer most likely face no higher risk for cancer themselves.

Crohn's disease, also called regional enteritis, is a chronic inflammation of the intestines that is usually confined to the terminal portion of the small intestine, the ileum. Ulcerative colitis is a similar inflammation of the colon, or large intestine. These and other inflammatory bowel diseases have been linked with an increased risk of colorectal cancer.

Polyps. Polyps are tissue growths, usually benign, that develop in the color or rectum, most often in patients over 50 years of age. When pathologists examine polyps removed from the colon, they classify them as either hyperplastic or adenomatous. Both types are benign, but some adenomas will become malignant. As a preventive measure, polyps should be removed (polypectomy).

Ureterosigmoidostomy. People who have had ureterosigmoidostomy, a surgical procedure to correct a birth defect in the bladder or to treat some bladder cancers, may develop tumors near the site of the defect, which is chronically exposed to urine and feces. Such patients have a 5 - 10% chance of developing colon cancer 15 - 30 years after the operation.

Diabetes. Many studies have identified an association between type 2 diabetes and colon cancer. Both diseases share common risk factors of obesity and physical inactivity, but diabetes itself is a risk factor for colorectal cancer. Both men and women who have diabetes are at risk.

Heart Disease. Coronary artery disease (CAD) increases the risk for colorectal cancer. Both CAD and colorectal cancer share important risk factors, including smoking, high fat diet, sedentary lifestyle, and obesity.

Dietary Factors

Some, but not all, studies have suggested that a high intake of fruits and vegetables can lower the risk for colorectal cancer. One study, for example, reported that these foods do not prevent polyps from forming but may help prevent them from becoming cancerous.

Phytochemicals. Many studies have demonstrated the cancer-fighting effects of plant chemicals called phytochemicals. Fruits and vegetables that contain phytochemicals can often be identified by colors:

Dark green (broccoli, spinach, kale, collard greens, mustard greens). These vegetables contain chemicals called isothiocyanates, which have been associated with a lower risk for cancer in general.
Red (red pepper, tomatoes, watermelon, raspberries, pink grapefruit). Lycopene is a chemical found in these foods that may have strong cancer-protective properties. Cooking tomatoes appears to increase their benefits.
Yellow-orange (carrots, pumpkin, sweet potatoes, oranges, tangerines). The colors in these foods are due to carotenoids. Carotenoids have been associated with health protection, although they may not have much effect on colon cancer itself.
Blue-black (many berries). Dark berries appear to have potent antioxidant chemicals that may be protective against cancer.

Organosulfurs are important food chemicals that are part of the allium family. Studies have reported health benefits from foods containing them. These compounds are found in garlic, leeks, onions, chives, scallions, and shallots. A review of 300 studies concluded that people who eat raw or cooked garlic regularly experience about two-thirds the risk of colorectal cancer as people who eat little or none. Another analysis, however, found the available evidence about garlic to be inconclusive. Garlic supplements, in any case, do not appear to be protective.

Fiber. Studies have been mixed on whether fiber (found in fruits, vegetables, and whole grains) protects the colon from cancer. For example, three major studies in 2002 and 2003 reported no difference in the development of colorectal polyps or cancer recurrence with high intake of fiber. On the other hand, results of the 2003 European Prospective Investigation into Cancer and Nutrition (EPIC) -- the largest study ever conducted on the role of diet in the development of cancer -- suggested that fiber is protective regardless of its source. However, in the study, the greatest benefits were observed for the left side of the colon and the least for the rectum. In any case, fiber, which is only found in plant products, may be beneficial for the heart and have other health advantages.

The role of fats in inflammatory bowel disease is complex and not fully known. A 2006 study from the Women’s Health Initiative found that a low-fat diet did not help reduce the risk for colorectal cancer. However, the study did not distinguish between types of fat.

Monounsaturated fats (olive, peanut, canola oils; avocados, nuts) and omega-3 polyunsaturated fats (fish, flaxseed oil, walnuts) are the healthiest types of fats.
Saturated fats (red meat, butter, high-fat dairy products) and trans-fats (hydrogenated fat found in snack foods, fried foods, commercial baked goods) are unhealthy types of fats.

Dietary guidelines recommend that adults limit the total fat in their diet to 25 - 35% of total daily calories. Saturated fat intake should be less than 7%, and trans fats less than 1%, of total daily calories. (Patients with heart disease or diabetes may need to limit unhealthy fat in their diet even further.) Most fats should come from polyunsaturated and monounsaturated fat sources.

[See In-Depth Report #43: Heart healthy diet; and #42: Diabetes diet.]

Evidence strongly suggests that red meat raises the risk for colon cancer development, and perhaps also recurrence. Red meat contains dietary iron, which has been associated with a higher risk for colon cancer.

High-temperature cooking (grilling, broiling, or pan-frying) has been specifically associated with increased risk for colon polyps and colon cancer. Overcooking meat increases the amount of carcinogens called heterocyclic amines, which has been associated with cancerous changes.

Milk, Lactose, and Probiotics. In one study, adults who drank the most milk had the lowest risk for colon cancer. A 2004 study published in the Journal of the National Cancer Institute supported this conclusion. In this review of 10 epidemiologic studies that included more than 500,000 people, those who consumed more milk and calcium had a lower risk of developing colorectal cancer. Milk contains not only calcium but also other compounds, such as lactose, that may help protect against colon cancer.

Yogurt specifically has been associated with a lower risk for colon cancer if it contains live active bacterial cultures, such as Lactobacillus acidophilus, that are called probiotics. These "friendly bacteria" appear to protect the colon from cancerous changes. (Acidophilus and other probiotic capsules are also available in health food stores.)

Calcium. Calcium, which is found in dairy products, is associated with colon cancer protection. Many studies have shown a possible protective effect from either high-calcium diets or calcium supplements. However, a 2006 study from the Women’s Health Initiative found that calcium and vitamin D supplements do not reduce women’s colorectal cancer risk. Many doctors still recommend that postmenopausal women take these supplements for bone health.

Obesity has been associated with colon cancer. In some studies of people under 67 years old, the amounts of fat and protein were less important than the total number of calories consumed: the higher the energy intake, the greater the risk for developing colon cancer. In older adults, high calorie intake did not make any significant difference. Other studies have indicated that eating too much sugar may increase the risk for colon cancer.

Studies conducted in several countries have found that drinking four or more cups of coffee a day is associated with a lower risk for colorectal cancer. Green tea may have also beneficial properties, but more research is needed in both of these areas.

Folate and B Vitamins. For years, many doctors have believed that the B vitamin folate (called folic acid) may help protect against colorectal cancer, particularly for people who are genetically predisposed to this disease. Folate is found in beans, citrus fruits, and green vegetables, but some studies have indicated that the greatest protective benefits come from taking supplements.

However, an important study published in 2007 in the Journal of the American Medical Association challenged this assumption. The study suggested that high-dose folic acid supplements do not prevent colorectal cancer, and may actually increase the risk for developing certain types of colorectal tumors. The study evaluated over 1,000 men and women who had a recent history of non-cancerous colorectal polyps. (Adenomatous polyps, also called colorectal ademomas, are the most common type of polyp found in colorectal cancer screenings.) The results indicated that patients who took 1 mg/day of folic acid supplements were more likely to develop new adenomatous polyps than patients who did not take supplements. Patients in the folic acid supplement group were also more likely to have advanced adenomas and more numerous adenomas.

Adenomatous polyps are benign tumors, but they can potentially develop into cancerous tumors. Researchers are continuing to investigate the role that folic acid plays in colorectal cancer risk and prevention. It is possible that folic acid may help prevent the initial appearance of adenomatous polyps, but increase the risk for additional polyp formation once they have begun to occur.

Antioxidant Supplements. Antioxidants are chemicals that help eliminate harmful particles called oxygen-free radicals that have been associated with cancerous changes. Some studies have associated supplements of the antioxidants selenium and vitamins A, C, D, and E with lower colon cancer risk, but most studies have found no protective effect.

Prevention

Studies indicate that daily exercise is one of the best ways to reduce the risk of colorectal cancer. The more vigorous the activity, the greater the benefit, but even moderate exercise (walking, stair-climbing) can help reduce colorectal cancer risk. The American Cancer Society (ACS) recommends that people engage in at least moderate exercise for 30 minutes or more at least 5 days a week. The ACS also notes that 45 minutes or more of moderate-to-vigorous activity at least 5 days a week may help further reduce cancer risk.

Some studies also suggest that regular exercise may be beneficial for patients who have been diagnosed with colorectal cancer. Two 2006 studies indicated that exercise may reduce the risk of colorectal cancer recurrence and death for patients with stage I - III cancer.

Nonsteroidal anti-inflammatory drugs (NSAIDs) are very common pain relievers that are available over-the-counter and by prescription. They include aspirin, ibuprofen (Motrin), naproxen (Aleve), and the COX-2 inhibitor celecoxib (Celebrex). Several studies have reported that NSAIDs help reduce the risk of colorectal cancer. However, regular use of NSAIDs, even in low doses, can increase the risk of gastrointestinal bleeding and stomach ulcers. Long-term use of NSAIDs can also increase the risk for heart attack and stroke, especially in people who have a history of heart disease. Several 2006 and 2007 studies in the New England Journal of Medicine reported that celecoxib prevented precancerous polyps, but the drug more than doubled patients’ risk for heart attack and other cardiovascular events.

A 2005 Nurse’s Health Study found that aspirin, but not other NSAIDs, does provide protection against colorectal cancer. However, the risk was only reduced for women who took 2 aspirin a day for more than 10 years. In addition, this dose level greatly increases the risk for gastrointestinal bleeding. Furthermore, a 2007 study in the New England Journal of Medicine suggested that aspirin’s protective effects may only apply to some types of colorectal cancer tumors. Another 2007 study, published in the Lancet, indicated that long-term daily use of aspirin can protect against polyps and colorectal cancer, but experts agree that aspirin’s risks do not outweigh its benefits for most people. (Some people who are at high risk for developing colorectal cancer may benefit from aspirin therapy.)

In March 2007, the U.S. Preventive Services Task Force (USPSTF) recommended against the routine use of aspirin and other NSAIDs to prevent colorectal cancer in people at average risk for this disease. (This recommendation does not apply to people who have a family history of colorectal cancer or who are at high risk for developing colorectal cancer due to other risk factors.) Long-term use of NSAIDs can increase the risk for gastrointestinal bleeding, kidney function problems, and heart problems. Aspirin can also increase the risk for hemorrhagic stroke. Due to these risks, the American Cancer Society and other professional associations also recommend against the use of NSAIDs or other types of medications for colorectal cancer prevention.

Medications containing 5-aminosalicylate (5-ASA) are sometimes given to patients with ulcerative colitis to help control inflammation. These drugs, which include sulfasalazine and mesalamine, are chemically related to aspirin. A 2005 review of clinical trials found that patients with ulcerative colitis who used 5-ASA were 49% less likely to develop colorectal cancer than patients who did not use these drugs

Some studies have suggested that cholesterol-lowering statin drugs may help reduce colorectal cancer risk. A 2006 study in the Journal of the National Cancer Institute did not find any protective benefit for statins.

Estrogen has been associated with a lower risk for colon cancer, perhaps because of specific enzymes that prevent cell proliferation. Drugs containing estrogen, then, may help high-risk women:

There is some evidence that hormone replacement therapy (HRT) reduces the risk of colon cancer in postmenopausal women. It carries other risks, however, including a higher risk for breast and uterine cancer and blood clots. A 2004 New England Journal of Medicine study found that while short-term use of estrogen plus progestin reduced the risk of developing colon cancer, combination HRT users who were diagnosed with the disease had more advanced forms of the cancer. Older women who are at higher risk for colon cancer might discuss risks and benefits of HRT with their doctor.
Oral contraceptives may reduce younger women's risk of colon cancer. Duration of use does not seem to be associated with decreased risk, but protection appears stronger for women who have more recently used oral contraceptives.

Diagnosis

Colon and rectal cancers are diagnosed using the screening tests discussed below. These tests can detect precancerous polyps and colorectal cancers at stages early enough for complete removal and cure.

Unfortunately, only 30 - 40% of adults over 50 years old (mostly in the upper socioeconomic group) have regular screening tests that could detect a cancer early enough for curative treatment. A survey reported that many people are not screened because they are too embarrassed. Those who had already had the tests were willing to have them again if they saved one additional day of their lives.

There is some debate about what is the best screening method. Current screening guidelines offer several different options for patients. Doctors agree that not enough people are screened and that these tests, if adopted with the same regularity as such screening tests as Pap smears, would save many lives. It is especially important for anyone at increased risk or with symptoms, such as rectal bleeding or ulcerative colitis, to have testing at an earlier age.

There is also debate about when people should stop being screened. A 2006 study in the Journal of the American Medical Association indicated that screening provides little benefit for elderly people, especially because colorectal cancers grow very slowly. The researchers suggest that doctors should carefully consider the risks versus benefits of screening patients age 80 and older.

Individuals should discuss with their doctors the risks and benefits of all screening procedures. Some controversy exists over how often people without risk factors for cancer should be screened and which detection method should be used for them.

Guidelines for Adults Age 50 and Over with Average Risk. The following are the five screening options recommended for people age 50 and over who have no symptoms and no family history of colon cancer:

Fecal occult blood test (FOBT) or fecal immunochemical test (FIT) every year
Flexible sigmoidoscopy every 5 years
FOBT or FIT every year plus sigmoidoscopy every 5 years
Double-contrast barium enema every 5 years
Colonoscopy every 10 years

Choosing between Colonoscopy and Sigmoidoscopy. The choice between colonoscopy and sigmoidoscopy for routine screening for older adults with average risk is an area of intense debate. The issues are as follows:

Sigmoidoscopy is less costly, less invasive, quicker, and safer than colonoscopy. Although it allows inspection of only the left side of the colon, any abnormal findings from sigmoidoscopy trigger a full colonoscopy. Therefore, experts estimate that sigmoidoscopy can detect 80% of all significant problems.
Colonoscopy is more sensitive than any other current screening method for detecting colon cancer. It can find 75 - 90% of colorectal cancers. If the goal were to reduce the number of cancer cases, regardless of cost, colonoscopy would be the preferred approach. Colonoscopy, however, is more expensive than sigmoidoscopy and has a slightly higher risk for complications (bowel tears or bleeding when a polyp is removed).

There are 3 basic tests for colon cancer: a stool test (to check for blood), sigmoidoscopy (inspection of the lower colon), and colonoscopy (inspection of the entire colon). All 3 are effective in catching cancers in the early stages, when treatment is most beneficial.

Screening, particularly with colonoscopy, in increased- and high-risk populations can save lives. The most important risk factors are a family history of colorectal cancer and personal history of colorectal cancer, polyps, or chronic inflammatory bowel disease. People with these risk factors should be screened before age 50 and may need more frequent screenings.

Guidelines for Increased-Risk Groups. Anyone with first-degree relatives diagnosed with colon cancer younger than 60, or with two relatives who have been diagnosed with colon cancer at any age, should consider beginning the standard screening regimen with a colonoscopy every 5 years, beginning at age 40 or 10 years before the youngest case in the family (whichever is earlier).

Men of African descent are also considered to be at increased risk for colon cancer and should discuss similar screening guidelines with their doctors.

Guidelines for High-Risk Groups. The following guidelines may be useful for specific high-risk groups.

People who have the mutated hereditary nonpolyposis colorectal cancer gene (MSH2 or MLH-). Frequent colonoscopy (for instance, every 1 - 2 years) beginning in their early 20s. (Regular screening for other cancers, such as uterine cancer, is also reasonable.)
People who have the mutated familial adenomatous polyposis (FAP) gene. Frequent screening with endoscopy (flexible sigmoidoscopy or colonoscopy) beginning in early puberty. Genetic testing is now recommended for family members of people with known FAP.
People with predisposing intestinal problems, such as widespread and active ulcerative colitis or Crohn's disease. Annual screening with colonoscopy with biopsies of suspicious areas.

Guidelines for Follow-Up After Detection of Precancerous Polyps. Patients who have had a previous examination in which polyps were detected (and removed) should have a repeat colonoscopy 1 - 3 years later, depending on the size, number, and type of polyps removed.

The digital rectal examination is used to detect tumors in the rectum, lower intestine, and prostate gland. The doctor inserts a lubricated-gloved finger into the patient's rectum and feels for lumps or other abnormalities. The exam is quick and painless but embarrassing for some. Fewer than 10% of colon cancers develop within the region that can be evaluated by a DRE, so it is not useful as a sole screening test.

Blood in bowel movements is not always visible, in which case it is called occult (hidden) blood. Fecal occult blood tests (FOBTs) are used to detect this hidden blood. The most common FOBT method is called the guaiac-based test. The patient is asked to supply up to six stool specimens in a specially prepared package. A small quantity of feces is smeared on specially treated paper, which reacts to hydrogen peroxide. If blood is present, the paper turns blue.

Accuracy. FOBTs can miss more than 75% of advanced cancers. Nevertheless, large studies have indicated that this simple test, performed annually, saves lives and may reduce the risk of dying from colon cancer by 15 - 33%. The following factors may affect its accuracy:

The levels of iron in the blood can affect results. Patients should not take iron supplements or eat red meats several days before the test.
Certain raw fruits and vegetables that contain the chemical peroxidase (cauliflower, horseradish, radishes, melons, and turnips) can cause a positive test reaction even if no blood is present.
Aspirin and NSAIDs are anticoagulants that can cause minor bleeding. They should not be taken for a week before the test. However, a 2005 study suggested that the prescription anticoagulant warfarin does not affect FOBT results.
Vitamin C and foods rich in this vitamin may cause a false negative reaction and should be avoided a few days before the test.
Bleeding from other causes, such as menstruation, hemorrhoids, gingivitis, or urinary infections, can produce blood in the stools and affect results.

Even if none of these conditions is present, a test that shows hidden blood does not necessarily mean that cancer is present. About 20 - 30% of people with occult blood have noncancerous polyps or other conditions, such as gastritis, and only 5 - 10% actually have cancer. Any abnormal result, however, requires further testing, such as colonoscopy.

Lack of Compliance. Compliance is a major problem. Patients are asked to perform the tests at home and send the test cards to the laboratory. Only 35 - 50% of patients actually follow through. Occult-blood tests that give results at home are available but are extremely inaccurate. In one large study, these tests failed to detect advanced cancer in about 62% of cases, although they may detect some early cancers.

If a digital rectal exam (DRE) or fecal occult blood test (FOBT) shows signs of trouble, several methods to visualize the colon are available. They include colonoscopy, sigmoidoscopy, and double-contrast barium enema. They have the following similarities and differences:

Sigmoidoscopy can only view the rectum and the left side of the colon, while colonoscopy and barium enemas allow a view of the entire large intestine.
Both flexible sigmoidoscopy and colonoscopy involve snaking a fiber optic tube through regions of the rectum and colon to view the walls of the intestine. The tube contains a tiny camera that transmits the image to a video screen. The use of an ultrasound (sound wave) scanner is proving to enhance viewing quality. Barium enemas simply use x-rays.
During either sigmoidoscopy or colonoscopy, the doctor is able to remove polyps or other abnormalities revealed by these procedures with surgical instruments inserted through the tube. It is not possible to remove polyps with a barium enema, which is not invasive.

Sigmoidoscopy. Sigmoidoscopy examines the rectum and the lower two feet of the colon. It cannot, however, detect the roughly half of cancers that occur in the right colon. Right-sided cancers are more common in older people.

The procedure uses a flexible fiber optic tube (it is thus referred to as flexible sigmoidoscopy) that contains a tiny camera and surgical instruments.
It lasts about 10 minutes and may be mildly uncomfortable, but it is not painful and is generally very safe. In one study, 70% of patients reported that the procedure was far less unpleasant than they had expected.

This procedure has been found to reduce the risk of fatal cancers in the rectal and sigmoid area by 60%. If polyps are detected, a colonoscopy is then used.

Colonoscopy. Colonoscopy is the most accurate testing method and can reduce cancer incidence by up to 90%. It is clearly indicated for anyone with an increased risk for colorectal cancer, including those with a personal or family history of the disease. As with sigmoidoscopy, a colonoscopy uses a flexible tube, but it is snaked through the entire large intestine.

For about a day before the procedure the patient eats nothing and drinks a laxative solution that cleans out the colon. The taste of the solution is unpleasant, although it has improved in recent years.
The procedure typically uses a sedative that produces a "twilight" sleep and often makes the procedure more comfortable than sigmoidoscopy.
Air may be introduced into the intestine to widen it and allow the tube to navigate curves. A colonoscopy avoids the risk of radiation associated with a barium enema, but it is important to note that even a colonoscopy does not detect all cancers.

Complications are rare, but include the following:

Hyponatremia. Hyponatremia is a low concentration of sodium in the blood. The complication may be caused by the effects of bowel cleaning before the procedure that can result in water retention and reductions in sodium. When severe, it can cause temporary neurological symptoms, such as confusion, lethargy, unsteadiness, and slurred speech. Researchers suggest that sodium concentrations be measured in patients who develop such symptoms after colonoscopy.
Bowel perforation (very low risk, about 2 in 1,000 procedures). The risk for bowel perforation is greater with colonoscopy than flexible sigmoidoscopy.
Bleeding at the site of biopsy or polyp removal.

Overall, colonoscopy is a safe procedure. However, according to a 2006 study in the Annals of Internal Medicine, serious complications occur in about 5 of every 1,000 colonoscopies. Most of these complications occurred when a biopsy or polyp removal was performed. (The risk for complications without biopsy or polyp removal is about 1 in every 1,000 colonoscopies.) This study looked at colonoscopies in general, including those that are done to diagnose the causes of a patient's symptoms. The risk may be lower for colonoscopies performed solely to screen for colorectal cancer.

Barium Enema. The double-contrast barium enema, which uses an x-ray image, is the less expensive alternative for viewing the entire colon. It is not as accurate as colonoscopy, and if any polyps or abnormalities are revealed on x-ray, a colonoscopy is then required to remove suspicious tissue, so it is now recommended much less often than in the past.

The barium enema is a valuable diagnostic tool that helps detect abnormalities in the large intestine (colon). The barium enema, along with colonoscopy, remains the standard in the diagnosis of colon cancer, ulcerative colitis, and other diseases of the colon.

Screening for familial adenomatous polyposis. Genetic screening for familial adenomatous polyposis (FAP) and hereditary nonpolyposis colon cancer (HNPCC) is now available and may be recommended for high-risk patients. The test for FAP detects a mutation in the adenomatous polyposis coli in up to 90% of people who carry it. Testing for HNPCC mutation is somewhat more complex.

Screening for insulin-like growth factor. A gene that regulates insulin-like growth factor (IGF-2) is functional during fetal development and then becomes inactive. Some evidence now suggests that people who have IGF-2 in adulthood have a higher risk for colon cancer. Blood tests for detecting IGF-2, then, may be helpful in identifying patients who should have more intensive screening. Currently, however, this is only used as a research tool.

Stool DNA Testing. A promising technique for colorectal cancer screening is the detection of altered DNA in cancer cells that have shed from the colon and are excreted in the stool. Such tests may prove to detect both inherited and noninherited genetic mutations. This may become a widely used tool in the future. However, larger clinical studies are needed.

Virtual Colonoscopy. A promising experimental technique called virtual colonoscopy allows three-dimensional imaging of the colon without using invasive instruments. As with standard colonoscopy, the patient takes a laxative first to clear out the intestine. The procedure itself involves pumping air into the colon and scanning the intestine using computed tomography (CT). It is very safe and takes about only 10 minutes. The procedure is similar in accuracy to conventional colonoscopy for detection of larger polyps (6 mm or more in diameter) and is also potentially less expensive. Colonoscopy is required, however, if suspicious areas are found, which may occur frequently with the CT procedure, since it erroneously identifies a high number of nonexistent polyps.

A study published in April 2004 in the Journal of the American Medical Association compared results of standard colonoscopy versus virtual colonoscopy in over 600 patients at nine major medical centers. Virtual colonoscopy had much lower rates of successfully finding polyps than standard colonoscopy. Virtual colonoscopy detected polyps of at least 6 mm in 39% of patients and polyps of at least 10 mm in 55% of patients. By contrast, standard colonoscopy detected 99% of polyps of at least 6 mm, and 100% of polyps of at least 10 mm. In addition, accuracy rates varied widely among the different hospitals. The authors advised that until more improvement in training and technique is achieved, virtual colonoscopy "is not yet ready for widespread clinical application."

Magnetic Resonance Colonography. Magnetic resonance colonography (MRC) is another non-invasive technique for visualizing the colon. The patient receives an enema containing a contrast substance, and then magnetic resonance images are taken. MRC is fast, comfortable, and less invasive than colonoscopy. Currently, however, there is a poor detection rate for flat tumors and for polyp tumors less than 10 mm in diameter.

Staging

A diagnosis of cancer will lead to staging and other tests to help determine the outlook and the appropriate treatments.

The large intestine is a long hollow organ lined with mucous membrane (mucosa). Muscle layers wrap around the entire length and help move food material through to the rectum.

Unlike many other cancers, the size of the tumor is not a major factor in determining the outcome of colorectal cancer. Of greater importance is how far the cancer has spread. To determine this, doctors will assign a stage to the tumor. There are several methods for staging. The older system, known as Dukes', categorizes four basic stages: A, B, C, and D. A more recent system refers to these stages as I, II, III, and IV but divides the categories slightly differently. The term "5-year survival" means that patients have lived at least 5 years since diagnosis. Most patients who live 5 years without a recurrence are considered to be cured of their disease.


Stage	Condition	5-Year Survival
A or I	Tumor superficially involves the inner lining of the intestine.	More than 90%
B or II	Tumor has penetrated through the muscle wall of the intestine but has not reached the lymph nodes.	70 - 85%
C or III	Lymph nodes are involved.	65% or below
D or IV	Tumor has spread to other organs (metastasized), usually the liver first.	5 - 9%

Click the icon to see an image of the stages of cancer.

Researchers are continually seeking to identify tumor markers, substances (usually found in blood samples) that will assist in the diagnosis of cancer and in monitoring effects of treatment.

Carcinoembryonic Antigen. High blood levels of a protein called carcinoembryonic antigen (CEA) sometimes indicate the presence of colon cancer. Unfortunately, it is also elevated in other cancers and in some noncancerous conditions. CEA is not effective as a screening tool for healthy people, but might eventually be helpful for patients with cancer.

An advanced diagnostic technique called polymerase chain reaction (PCR) can detect genetic evidence of CEA. One study indicated that when these microscopic footprints of colon cancer are detected in the lymph nodes of patients with Stage II cancer (whose lymph nodes otherwise appear to be not involved with cancer), the outlook is similar to that of patients with Stage III cancer. Patients without this so-called micrometastasis have a very favorable prognosis. Further research is needed, however, before PCR can be used in widespread practice.
In patients with a history of, or active, colon cancer, follow-up measuring of blood CEA levels may be helpful in detecting recurrence of the cancer and effectiveness of treatments.

Defective P53 Gene. The presence of a defective p53 gene is a marker for very poor prognosis in patients with advanced colon cancer. In its normal state, the gene is important for regulation of cell growth. Testing for this abnormality, however, is not widely done because it is not clear how to use this information.

Other Tumor Markers. Other tumor markers under investigation include a protein called GLUT1, cancer antigen 19-9 (CA 19-9), matrix metalloproteinase-9 (MMP-9) RNA, HER-2/neu oncoprotein, transforming growth factor beta-1 (TGF-beta-1), and CD44.

Click the icon to see an image of drawing blood for culture.

A technique known as a sentinel node biopsy is increasingly performed by experienced surgeons in selected patients. This procedure is used to determine if cancer has spread beyond the nodes, possibly reducing the need for complete axillary lymphadenectomies. It involves the following:

The procedure uses an injection of a tiny amount of a tracer, either a radioactively-labeled substance (radioisotope) or a blue dye, into the tumor site.
The tracer or dye then flows via the lymphatic system into the so-called sentinel node. This is the first lymph node to which any cancer would spread.
The sentinel lymph node and possibly one or two others are then removed.
If they do not show any signs of cancer, it is highly likely that the remainder of the lymph nodes will be cancer free, and further surgery becomes unnecessary.

It is still not known if the sentinel node biopsy has any survival advantages compared to the standard procedures with lymph nodes removal. However, one study indicated that careful and complete removal of potentially cancerous lymph nodes is still very important for improving survival in patients with Stage II and III colorectal cancer.

Whole-body imaging scans that combine positron emission tomography (PET) and computed tomography (CT) may be helpful in accurately staging colorectal cancer, according to preliminary research published in 2006 in the Journal of the American Medical Association.

Prognosis

Survival rates for colorectal cancer have been rising in recent years. The 5-year survival rate is as high as 90% for cancer that has not spread to the lymph nodes (localized cancer). When cancer has spread to lymph nodes and other parts of the body, survival rates drop to 65% and below. Because many cancers are detected at later stages, the overall survival rate is currently about 60%. African-Americans and other minorities tend to have lower survival rates than Caucasians. Studies suggest, however, these higher mortality rates are largely due to less access to optimal health care, including appropriate surgical care and aggressive treatments.

In most cases, age is not a factor in treatment success. Good survival rates are achieved in the elderly as well as in young people. Chances for survival are less in Stage II cancers if the intestine is obstructed or perforated. If cancer has spread to lymph nodes (Stage III), the outlook is better if three or fewer lymph nodes are involved. Treatment can prolong life even when cancer has spread.

Surgery

Surgical removal of the tumor ("resection") along with any affected surrounding tissue is the standard initial treatment for potentially curable colorectal cancers (cancers that have not spread beyond the colon or lymph nodes). Drug and radiation therapy are often used for advanced cancers and are continuously being tested with surgery in different combinations and sequences.

Although choosing a qualified surgeon is critical, choosing a hospital experienced in procedures is also important. The more often colon cancer surgery is performed at a given hospital, the lower the mortality rate at that hospital is likely to be.

Unless cancer is very advanced, most tumors are removed by an operation known as colectomy:

Colectomy involves removing the cancerous part of the colon and nearby lymph nodes.
The surgeon then reconnects the intestine.
If the surgeon cannot reconnect the intestine, usually because of infection or obstruction, the surgeon will perform a colostomy. The need for colostomies is higher after surgery for rectal cancer. In most cases of colon cancer, colostomies are not needed. [See "Colostomy" below.]

Click the icon to see an illustrated series detailing colon cancer treatment.

The Surgical Approach. The standard technique for a colectomy is open, invasive surgery. Laparoscopy, sometimes called “keyhole surgery,” is a less invasive method. Laparoscopy is still considered an investigational technique for treating colon cancer, but it is gaining more acceptance and showing good results in clinical trials.

Open Surgery:

Open surgery uses a wide incision to open the patient's abdomen. The surgeon then performs the procedures with standard surgical instruments. This is the usual method for performing colectomy.

Laparoscopy:

Laparoscopy uses a few small incisions through which the surgeon passes a fiber optic tube (laparoscope) containing a small camera or tiny instruments. It is generally used for early colon cancer (for tumors less than 2 centimeters or for well-defined tumors less than 3 centimeters).
A 2004 New England Journal of Medicine study found that patients who received laparoscopic colectomy had similar rates of surgical complications, cancer recurrence, and survival as those who received traditional open surgery. However, the patients who had laparoscopy recovered faster and did not need as many narcotic painkillers.
Several 2005 studies indicated that laparoscopy works as well as conventional surgery for treatment of colon cancer. However, laparoscopy does not appear to be as effective for rectal cancer.

Click the icon to see an image detailing pelvic laparoscopy.

Click the icon to see an illustrated series detailing a resection of the large intestine.

Other Investigational Measures. Researchers are testing expandable metal tube-like devices called stents to keep the intestine open. Stents may be used before a procedure to allow bowel cleansing or for long-term use to keep open colons that can't be operated on.

A colostomy is performed in order to bypass or remove the lower colon and rectum. The procedure generally involves creating a passage, called a stoma, through the abdominal wall that is connected to the colon. The feces pass through this passage and are eliminated. Patients must learn how to care for the stoma and keep the area sanitary.

A colostomy usually will have one opening (single-barreled), or there may be two loops opening through the skin (double-barreled).

Usually the colostomy is temporary and can be reversed by a second operation after about 3 - 6 months. It the rectum and sphincter muscles in the rectum need to be removed, the colostomy is permanent. Permanent colostomies are more common when the cancerous regions are within 2 - 3 centimeters of the anus. Fortunately, surgical advances and knowledge of the extent of safe margins are reducing the need for permanent colostomies.

Click the icon to see an illustrated series detailing a colostomy procedure.

Managing Permanent Colostomies. In cases where the colostomy is permanent, the patient must wear a colostomy pouch, which sticks to the skin using a special glue. Pouches are available as one- or two-piece systems. The one-piece system is simpler, but the two piece system allows replacement of the pouch without removing the tape.

For best results, the pouch should be emptied when about one-third full. It should be replaced 1 - 2 times a week, depending on signs of leakage (itching or burning of the skin near the stoma). The pouches are odor proof.

Surgical treatments for cancer in the rectum are complex since they involve muscles and tissue that are critical for urinary and sexual function.

Local Excision or Polypectomy for Early Stages. In order to preserve the function of the anal sphincter and prevent the need for colostomy, Stage I and Stage II tumors may be removed by local excision, sometimes followed by chemotherapy and radiation. In this procedure, the tumor is cut out without removal of a major section of rectum. In some cases cancer recurs, but a second operation may be possible. Another treatment for early-stage rectal cancer, called electrocoagulation, destroys tumors using a high frequency electric current. It is being tested in clinical trials.

Radical Resection. In about a third of cases of rectal cancer, the cancer occurs in the lower part of the rectum, where between 70 - 80% of cancers have spread beyond the rectal wall. These patients need a radical resection, in which surrounding structures, including the sphincter muscles that control bowel movements, must often be removed.

The use of chemotherapy and radiation prior to surgery may prevent the need for permanent colostomy in some patients. This is an active area of clinical research, and trials are under way to address this issue. Another technique, called coloanal anastomosis, reconstructs the area to avoid the need for colostomy, and may be appropriate in some patients.

Total Mesorectal Excision. Total mesorectal excision (TME) involves dissection and removal of the entire cancerous area of the rectum along with surrounding fatty regions where the lymph nodes are located (the mesorectum). When successful, TME preserves the sphincter muscle, reducing the need for a permanent colostomy. Increasing use of this procedure is resulting in lower recurrence rates, lower levels of impotence and incontinence, and better overall survival rates compared to other resection techniques. Some experts now recommend it as a first choice for certain patients with locally advanced rectal cancer.

Combining chemotherapy and radiation either before or after TME is yielding promising long-term results and a low risk for local recurrence. There are many questions, however, and it is not clear which approach is better for specific patients.

Side effects of colon surgery include:

Sexual dysfunction. This is of particular concern. In general, colostomy does not usually affect sexual function. However, wide rectal surgery can cause short- or long-term sexual dysfunction. Sildenafil (Viagra) may help men who experience this after surgery.
Irregular bowel movements.
Gas and flatulence. Pouching filters are available to reduce gas. Certain foods produce more gas than others -- usually within 6 - 8 hours after ingestion for colostomy patients. They include beans, oat bran, most fruit, and certain vegetables (cabbage, cauliflower, Brussels sprouts, broccoli, and asparagus). To prevent swallowing air, patients should avoid sipping through straws, chewing gum, and chewing with their mouths open.
Diarrhea.
Bladder complications.
Sense of urinary urgency.
Fecal incontinence. Patients with rectal surgery have a higher risk for bowel dysfunction than those who had a colostomy.
Complications in or around the stoma. These can occur early after surgery to many years after the procedure. They include skin infection or breakdown, hernias, narrowing of the stoma, bleeding, and collapse.

There are no dietary restrictions, although many patients avoid foods that can produce gas. Everyone should drink plenty of fluids and get sufficient fiber.

The potential side effects of sexual and bowel dysfunction for colorectal surgical patients can be devastating, although many patients do very well and live normal productive lives. Positive emotions play a strong role in recovery. Patients who are depressed should discuss with a doctor all aspects of treatment that affect the quality of life, and consider seeking support groups.

Medications

Chemotherapy uses drugs that kill cancer cells throughout the body. There are two situations in which chemotherapy is used:

The adjuvant setting. Adjuvant refers to the use of chemotherapy after surgery in patients with Stage III tumors and selected patients with high-risk Stage II tumors (disease that is potentially curable). The goal of this therapy is to eliminate any cancer cells that surgery may have missed, thereby preventing recurrence and increasing the chance of cure. Patients of all ages, including the elderly, can benefit.
In metastatic disease. In patients with metastatic disease (where the cancer has spread to other parts of the body) the goal of chemotherapy is to shrink tumors, improve symptoms and quality of life, and lengthen life.

In the adjuvant setting, there are some differences in chemotherapy treatments between colon and rectal cancers:

Chemotherapy for Stage II is considered standard care for Stage II rectal cancer but is under debate for colon cancer.
Chemotherapy is standard for patients with Stage III colon cancer. Chemotherapy is also standard for patients with Stage III rectal cancer but is used in combination with radiation.

Chemotherapy for Stage II Colon Cancer. Adjuvant chemotherapy for Stage II colon cancer is controversial. Such patients tend to have a good outcome after surgery, and the positive effects of chemotherapy have been difficult to demonstrate. To date, the survival advantage of adjuvant chemotherapy in this group has been reported to be only in the range of 2%. However, better trials are still needed to confirm or refute the benefits in specific patient groups.

Although not yet known with certainty, some data suggest that certain patients with Stage II cancer may be at higher risk of recurrence and would theoretically benefit from adjuvant therapy. These include patients with cancers that have:

Obstructed the bowel
Perforated the wall of the colon
Adhered to structures outside the intestine

Advanced diagnostic techniques are under investigation for helping to select appropriate candidates for adjuvant therapy. None of these methods, however, are ready to be used routinely to help make treatment decisions. The decision whether to pursue chemotherapy for Stage II disease should be made after careful discussion between the patient and their oncologist, especially after features, such as bowel perforation or obstruction, are taken into account.

Chemotherapy for Stage III Colon Cancer. Since the early 1990s, adjuvant chemotherapy with 5-FU and leucovorin has been the standard of care for Stage III colon cancer. In recent years, the FOLFOX (5-FU, leucovorin, oxaliplatin) regimen has also been used for chemotherapy following surgery. Numerous trials have shown that adjuvant chemotherapy in this setting reduces the absolute risk of death from colon cancer by about one-third and improves survival by 10%. Clinical trials are also investigating combinations of other drugs.

Chemotherapy for Advanced Colorectal Cancer. Chemotherapy is either given directly into the arteries of the liver or intravenously (through a vein) with 5-FU and leucovorin. Oxaliplatin is sometimes added, but recent evidence suggests that the targeted therapy biologic drug bevacizumab may be a better addition. Other alternative chemotherapy choices are capecitabine, or irinotecan combined with cetuximab. Radiation therapy may be used in place of chemotherapy or in combination with it. Studies indicate that chemotherapy offers only a modest improvement in survival, but may help reduce symptoms.

Seven drugs are currently approved for colorectal cancer chemotherapy:

5-fluorouracil (5-FU, Adrucil), which is often given in combination with leucovorin (Wellcovorin). Leucovorin is a vitamin that helps boost the effectiveness of 5-FU.
Capecitabine (Xeloda)
Oxaliplatin (Eloxatin)
Irinotecan (Camptosar)
Bevacizumab (Avastin)
Cetuximab (Erbitux)
Panitumumab (Vectibix)

Capecitabine is a pill form of 5-FU. The other drugs are administered intravenously. Many of these drugs are given in combination with each other. Common chemotherapy combination regimens include:

5-FU / LV (5-FU and leucovorin)
FOLFOX (5-FU with leucovorin and oxaliplatin)
FOLFORI (5-FU with leucovorin and irinotecan)
IFL (Irinotecan, 5-FU, leucovorin)
XELOX (Capecitabine and oxaliplatin)

Side effects occur with all chemotherapeutic drugs. They are more severe with higher doses and increase over the course of treatment. Because cancer cells grow and divide rapidly, anticancer drugs work by killing fast-growing cells. This means that healthy cells that multiply quickly can also be affected. The fast-growing normal cells most likely to be affected are blood cells forming in the bone marrow, and cells in the digestive tract, reproductive system, and hair follicles. Nausea and vomiting is a very common side effect, but drugs such as ondansetron (Zofran) can help provide relief. In general, side effects are nearly always temporary, and medications can help manage them. Most patients are able to continue with normal activities for all but perhaps 1 - 2 days a month.

5-Fluorouracil (5-FU) with Leucovorin. Adjuvant therapy using 5-fluorouracil, either alone or with leucovorin (5-FU/LV), is the standard treatment for patients with high-risk colon cancer (Stage III or select patients with Stage II tumors). Leucovorin, also called folinic acid, is a form of the B vitamin folic acid, which helps increase 5-FU’s effectiveness. Patients are given a series of cycles that usually continue for at least 6 months.

There are many different ways of giving 5-FU, including intravenously over several hours once a week, intravenously daily for 5 consecutive days every month, or as continuous infusion with a portable pump.

The side effects can be quite different, depending on the way 5-FU is given, and women may be more susceptible than men. In one analysis, 53% of women and 40% of men experienced severe side effects, while response rates and survival were similar for both sexes. Many patients, however, tolerate 5-FU with leucovorin well, with manageable side effects. The most common side effects include nausea and vomiting, diarrhea, loss of appetite, hair loss, swelling of hands and feet, rashes, and mouth sores.

Irinotecan. Irinotecan (Camptosar) blocks an enzyme essential for cell division. Irinotecan can be given alone or in combination with 5-FU and leucovorin. This combination therapy (irinotecan plus 5-FU/LV) is also referred to as the "Salz regimen," or IFL. When it was approved in the mid 1990s, irinotecan was the first new drug developed for colon cancer in over 30 years. Studies have shown that irinotecan combined with 5-fluorouracil and leucovorin (5-FU/LV) significantly delays the time at which tumors progress and improves survival in metastatic cancer compared to 5-FU/LV alone. While the survival advantage is small, the combination has become the standard of care for metastatic cancer. Of concern, however, are studies that have reported an increased risk of death from toxic effects with the use of the three-drug combination. These deaths appeared to be related to blood-clotting complications. Doctors should carefully monitor dosages. Diarrhea is a common side effect of irinotecan.

Capecitabine. Capecitabine (Xeloda), an oral form of 5-FU, was approved in 2001 as a treatment for metastatic colorectal cancer. It is the only pill approved for colorectal cancer. A major 2005 study, published in the New England Journal of Medicine, found that capecitabine works as well as the standard 5-FU/LV regimen and causes significantly fewer side effects. The study involved patients with Stage III colon cancer who had undergone surgical removal of the tumor. In 2005, capecitabine was approved for postsurgical treatment of patients with Dukes’ C colon cancer. Capecitabine is also showing promise in combination with radiation therapy for rectal cancers.

Oxaliplatin. Oxaliplatin (Eloxatin) is related to cisplatin, a widely used platinum-based chemotherapy drug. Oxaliplatin is used in combination with 5-FU and leucovorin. (This triple combination therapy is called the FOLFOX regimen.) Oxaliplatin was first approved in 2002 for use in combination with 5-FU and leucovorin as a second-line treatment for cancer that has progressed after initial therapy.

Since 2002, oxaliplatin has received additional approvals as a first-line treatment for advanced colorectal cancer, and as a post-surgical treatment for patients who have undergone tumor resection.

Oxaliplatin can cause pain and tingling sensations in the hands and feet (neuropathy) that is worsened by exposure to cold. Recent research suggests that adding xaliproden (Xaprila) to the FOLFOX regimen may help reduce the frequency of neuropathy without interfering with the benefits of chemotherapy. Xaliproden is a drug used to treat the neurological disease amyotrophic lateral sclerosis (also known as Lou Gehrig's disease).

Bevacizumab. Bevacizumab (Avastin) was approved in February 2004 as a first-line treatment for patients with metastatic colorectal cancer (advanced cancer that has spread in the body). It is used in combination with IFL (irinotecan, 5-FU, leucovorin). Bevacizumab is a genetically engineered monoclonal antibody that targets and inhibits vascular endothelial growth factor (VEGF), a protein that regulates angiogenesis (the development of new blood vessels that feed a tumor's blood supply). It is the first anti-angiogenic therapy approved for the treatment of colorectal cancer.

In a study of 800 patients with metastatic colorectal cancer, bevacizumab administered intravenously along with IFL extended survival by about 5 months longer than IFL alone. Common side effects of bevacizumab include nosebleeds, fatigue, diarrhea, and high blood pressure. Less common side effects include stroke, heart attacks, angina, and formation of holes in the colon and stomach (gastrointestinal perforation).

Cetuximab. Cetuximab (Erbitux) was approved in February 2004 for the treatment of metastatic colorectal cancer. This monoclonal antibody drug targets epidermal growth factor receptor (EGFR), a protein required by cancer cells in order to proliferate. It can be used either in combination with irinotecan or alone for patients who have not responded to irinotecan. Studies of the cetuximab-irinotecan combination suggest it can help in tumor shrinkage. It has a modest effect on survival, prolonging patients’ lives by about an additional month.

Panitumumab. Panitumumab (Vectibix) was approved in September 2006 for treatment of colorectal cancer that has metastasized following standard chemotherapy. Like cetuximab, panitumumab is a monoclonal antibody drug that targets EGFR. In clinical trials, panitumumab helped delay disease progression and prolong survival by about 3 months. About 8% of patients experienced tumor shrinkage. Common side effects of this drug include skin rash, fatigue, abdominal pain, nausea, and diarrhea or constipation. Serious side effects include pulmonary fibrosis, severe skin rash, and skin reactions at the infusion site.

One of the most promising recent developments in cancer treatment research has been the emergence of so-called "targeted therapies." Traditional chemotherapy drugs can be effective, but because they do not distinguish between healthy and cancerous cells their generalized toxicity can cause severe side effects. Targeted therapies work on a molecular level by blocking specific mechanisms associated with cancer cell growth and division. Because they selectively target cancerous cells, they may induce less severe side effects. In addition, these drugs hold the promise of creating options for more individualized cancer treatment based on a patient's genotype. In the future, diagnostic tests may help doctors identify which patients are more likely to respond successfully to specific drugs.

Biologic therapies use the body's immune system to attack the cancer (immunotherapy). These drugs are derived from biological sources and include vaccines, monoclonal antibodies (MAbs), and gene therapies. Many targeted therapies are classified as biologics. Bevacizumab (Avastin), cetixumab (Erbitux), and panitumumab (Vectibix) are currently the three biologic drugs approved for colorectal cancer treatment, but many other drugs are in development.

Targeted therapies involve many different types of drugs and molecular pathways. These include:

Angiogenesis Inhibitors. Anti-angiogenesis drugs inhibit the formation of new blood vessels that supply tumors with the blood, oxygen, and nutrients vital to tumor growth. Angiogenesis inhibitors, such as the monoclonal antibody bevacizumab (Avastin), target vascular endothelial growth factor (VEGF). Cediranib (Recentin), formerly AZD2171, is a new angiogenesis inhibitor that is in Phase III clinical trials for treatment of colorectal cancer.

Tumor Growth Factor Inhibitors. Tumor growth factors, such as epidermal growth factor, stimulate cell growth. Cetixumab (Erbitux) and panitumumab (Vectibix) are the two currently approved colorectal cancer drugs that target the epidermal growth factor receptor (EGFR). Nimotuzumab (TheraCIM) is currently being studied in combination with irinotecan in Phase III trials.

Tyrosine Kinase Inhibitors. Tyrosine kinase is an enzyme associated with EGFR that is involved with the signaling mechanisms that prompt cell growth. The EGFR/tyrosine kinase inhibitor erlotinib (Tarceva), which is approved for the treatment of pancreatic and lung cancers, is being investigated as an adjuvant treatment for metastatic colorectal cancer. Sunitinib (Sutent), which is approved for renal cell carcinoma, is another tyrosine kinase inhibitor in Phase III trials for colorectal cancer.

Radiation Treatment

Radiation therapy uses x-rays to kill cancer cells that might remain after an operation or to shrink large tumors before an operation so that they can be removed surgically. The object of radiation therapy is to damage the tumor as much as possible without harming surrounding tissues. Radiation may be administered in the following ways:

Externally by an x-ray machine (external beam radiation).
By passing radioactive pellets through thin plastic tubes inserted into the intestine.
By implanting tiny radiation seeds directly into the tumor (brachytherapy).
Computer imaging techniques providing 3-dimensional pictures of the cancerous area are allowing precise targeting of radiation to the tumor.

Postoperative radiation treatment combined with chemotherapy is common practice for patients with rectal cancer in Stages II and III. Such patients are at risk of recurrence both at the site of their original tumor and elsewhere in the body. Although there can be significant long-term side effects, the combination of 5-FU and radiation is still considered standard after surgery.

The standard procedure in the U.S. is to apply radiation after surgery (postoperative). Pre-operative chemotherapy and radiation, however, are sometimes used to preserve sphincter-muscle function and reduce the chance that a patient will need a colostomy. Furthermore, some studies suggest that the use of radiation before surgery reduces the likelihood of recurrences and may slightly prolong survival in some patients with rectal cancer. (It has no additional advantages, however, if the subsequent surgery does not completely remove the cancerous regions.) Studies comparing preoperative and postoperative chemotherapy and radiation are currently under way.

Radiation therapy can also be used during surgery (a procedure called intra-operative radiotherapy). It allows the surgeon to move healthy tissue out of the path of the radiation beam.

Short-term side effects of radiation include:

Diarrhea
Skin irritation around the anus
Incontinence
Fatigue
Bowel movement problems

Longer-term complications may include:

Incontinence
Hip and pelvic fractures
Diarrhea
Increased risk for bowel obstruction

Follow-up Testing

The American Society of Clinical Oncology (ASCO) sets guidelines for follow-up testing to detect recurring cancer after the completion of treatment. The following guidelines are based on ASCO’s 2005 updated recommendations.

Most colorectal cancer recurrences happen within 3 years after surgery. American Society of Clinical Oncology recommends that a colorectal cancer patient sees their doctor for a physical examination every 3 - 6 months for the first 3 years, every 6 months for the fourth and fifth years, and at the doctor's and patient's discretion during subsequent years.

Patients should have a colonoscopy 3 years after surgery. If the results are normal, patients should then receive a colonoscopy every 5 years. Some patients with hereditary types of colorectal cancer may need more frequent screenings.

A flexible sigmoidoscopy is recommended every 6 months for 5 years for patients with Stage II or III rectal cancer who did not receive radiation therapy.

Carcinoembryonic antigen (CEA) levels should be measured every 3 months after surgery for 3 years in patients with Stage II or III cancer. High CEA levels in the blood may indicate that the cancer has spread to other parts of the body.

Patients at high risk for cancer recurrence should receive an annual computerized tomography (CT) scan for the first 3 years after treatment. The CT scan can help determine if cancer has spread to the lungs or liver. Patients who have had rectal cancer, and did not have radiation therapy, should receive a pelvic CT scan. The scan is not recommended for most lower-risk patients with Stage I or II colorectal cancer.

American Society of Clinical Oncology does not recommend other follow-up blood tests such as complete blood count, liver function tests, fecal occult blood tests. There appears to be no additional benefit for these tests.

Treatment for Metastasized Colorectal Cancer

The liver is the most frequent site for colorectal cancers to spread (metastasized). Here, treatments may slow the spread of cancer and even prolong survival. Cure is very rare.

When cancer has spread, surgery to remove or bypass obstructions in the intestine may be performed. In these circumstances, surgery is considered palliative in that it may improve symptoms but will not lead to cure. In rare cases, metastatic colon cancer may be cured with surgical removal of tumors in areas to which the cancer has spread, such as the liver, ovaries, and lung. The liver is the most common site of spread. Only selected patients may be eligible for such surgery, but in these patients, 5-year survival has been 25% or higher.

Chemotherapy may help improve symptoms and possibly prolong survival in metastasized colorectal cancers. Several investigational drugs are being tested. Doctors are also testing chemotherapy administered directly into the liver -- a treatment called hepatic arterial infusion (HAI). A 2006 study found that hepatic arterial infusion improves survival and quality of life for patients whose cancer has spread to the liver. The study indicated that HAI works better for these patients than chemotherapy delivered intravenously.

Other investigative techniques used to destroy liver tumors include:

Cryosurgery. This approach freezes the tumor or surrounding tissue.
Embolization. Embolization employs a catheter to deliver substances into the liver that block blood vessels and therefore starve the tumor. Chemotherapy is often administered during this procedure.
Radiation.

For end-stage cancer, hospice care is a compassionate option.

Resources

www.cancer.org -- American Cancer Society
www.cancer.gov -- National Cancer Institute
www.oncolink.org -- OncoLink cancer information
www.asco.org -- American Society of Clinical Oncology
www.plwc.org -- People Living with Cancer
www.nccn.org -- National Comprehensive Cancer Network
www.cancer.gov/clinicaltrials -- Find clinical trials

References

Chan AT, Ogino S, Fuchs CS. Aspirin and the risk of colorectal cancer in relation to the expression of COX-2. N Engl J Med. 2007 May 24;356(21):2131-42.

Cole BF, Baron JA, Sandler RS, Haile RW, Ahnen DJ, Bresalier RS, et al. Folic acid for the prevention of colorectal adenomas: a randomized clinical trial. JAMA. 2007 Jun 6;297(21):2351-9.

Flossmann E, Rothwell PM; British Doctors Aspirin Trial and the UK-TIA AspirinTrial. Effect of aspirin on long-term risk of colorectal cancer: consistent evidencefrom randomised and observational studies. Lancet. 2007 May 12;369(9573):1603-13.

Kerr DJ, Dunn JA, Langman MJ, Smith JL, Midgley RS, Stanley A, et al. Rofecoxib and cardiovascular adverse events in adjuvant treatment of colorectal cancer. N Engl J Med. 2007 Jul 26;357(4):360-9.

Levin TR, Zhao W, Conell C, Seeff LC, Manninen DL, Shapiro JA, Schulman J. Complications of colonoscopy in an integrated health care delivery system. Ann Intern Med. 2006 Dec 19;145(12):880-6.

Meyerhardt JA, Niedzwiecki D, Hollis D, Saltz LB, Hu FB, Mayer RJ, et al. Association of dietary patterns with cancer recurrence and survival in patients with stage III colon cancer. JAMA. 2007 Aug 15;298(7):754-64.

U.S. Preventive Services Task Force. Routine aspirin or nonsteroidal anti-inflammatory drugs for the primary prevention of colorectal cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2007 Mar 6;146(5):361-4.

Veit-Haibach P, Kuehle CA, Beyer T, Stergar H, Kuehl H, Schmidt J, et al. Diagnostic accuracy of colorectal cancer staging with whole-body PET/CT colonography. JAMA. 2006 Dec 6;296(21):2590-600.

Review Date:
9/8/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Coronary artery disease

FitSugar — Wed, 08 Oct 2008 17:35:07 -0700

In This Report

Highlights
Introduction
Prognosis
Risk Factors
Diagnosis
Managing Heart Disease
Anti-Clotting Medications...
Other Medications
Surgery
Coronary Artery Bypass Graf...
Angioplasty and Stents
Other Treatments
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Angioplasty Versus Drugs

Angioplasty works no better than drug therapy (high blood pressure, cholesterol, anti-platelet, and other medication) in preventing heart attack and stroke in patients with stable coronary artery disease (CAD), according to an important New England Journal of Medicine study. Experts still recommend angioplasty for patients with unstable or severe CAD.

Stents

Stents coated with drugs may have a slightly higher risk of causing blood clots than bare metal stents, according to FDA meetings held in late 2006. Researchers still need to conduct more research before reaching final conclusions.
Drug-coated stents work well when they are used for patients with specific types of heart conditions, indicate several studies published in the New England Journal of Medicine. However, problems may develop when these stents are used for “off-label” purposes. Experts are also concerned that both bare metal and drug-coated stents may be used too frequently.
Patients who receive a drug-coated stent must take both aspirin and an anti-platelet thienopyridine drug (usually clopidogrel) for at least 1 year after the stent is inserted, advises an important statement from the American Heart Association. Patients who cannot take a thienopyridine drug should receive a bare metal stent instead of a drug-coated stent.

Anti-Bleeding Drugs for Coronary Artery Bypass Graft (CAGB)

Aprotinin (Trasylol), a drug used to control bleeding during CABG, is more dangerous than other types of anti-bleeding drugs, according to a 2007 study in the Journal of the American Medical Association. Many experts now recommend against its use.

Diagnosis

Blood tests for biomarkers do not provide much more predictive information than standard disease risk factors, suggest several recent studies. In a 2006 study published in the New England Journal of Medicine, researchers found that risk factors such as high blood pressure, high cholesterol, and diabetes are still the best methods for predicting the likelihood of heart disease and heart-related death.

Introduction

The heart is the human body's hardest working organ. Throughout life it continuously pumps blood enriched with oxygen and vital nutrients through a network of arteries to all parts of the body's tissues.

The external structures of the heart include the ventricles, atria, arteries, and veins. Arteries carry blood away from the heart while veins carry blood into the heart. The vessels colored blue indicate the transport of blood with relatively low content of oxygen and high content of carbon dioxide. The vessels colored red indicate the transport of blood with relatively high content of oxygen and low content of carbon dioxide.

In order to perform the difficult task of pumping blood to the rest of the body, the heart muscle itself needs a plentiful supply of oxygen-rich blood, which is provided through a network of coronary arteries. These arteries carry oxygen-rich blood to the heart's muscular walls (the myocardium).

Click the icon to see an image of the anterior heart arteries.

If blood flow to the myocardium is interrupted, an injury known as an infarct occurs. This is also known as myocardial infarction or, more commonly, a heart attack.

Click the icon to see an animation about coronary artery disease.

Coronary artery disease is the end result of a complex process called atherosclerosis (commonly called "hardening of the arteries"). This causes blockage of arteries (ischemia ) and prevents oxygen-rich blood from reaching the heart. There are many steps in the process leading to atherosclerosis, some not fully understood.

Click the icon to see an image of atherosclerosis.

Increasingly, however, researchers are studying the interactions between cholesterol and processes known as oxidation and the inflammatory response.

Cholesterol and Lipoproteins. The story begins with cholesterol and sphere-shaped bodies called lipoproteins that transport cholesterol.

Cholesterol is a white, crystalline substance that is found in all animal cells and in animal-based foods. It is critical for many functions, but under certain conditions cholesterol can have harmful effects.
The lipoproteins that transport cholesterol are referred to by their size. The most commonly known are low-density lipoproteins (LDL) and high density lipoproteins (HDL). LDL is often referred to as the "bad" cholesterol and HDL as the "good" cholesterol.

Click the icon to see an image of cholesterol inside an artery.

Oxidation. The damaging process called oxidation is an important trigger in the atherosclerosis story.

Oxidation is a chemical process in the body caused by the release of unstable particles known as oxygen-free radicals. It is one of the normal processes in the body, but under certain conditions (such as exposure to cigarette smoke or other environment stresses) these free radicals are overproduced.
In excess amounts, they can be very dangerous, causing damaging inflammation and even affecting genetic material in cells.
In heart disease, free radicals are released in artery linings and oxidize low-density lipoproteins (LDL). The oxidized LDL is the basis for cholesterol build-up on the artery walls and damage leading to heart disease.

Inflammatory Response. For the arteries to harden there must be a persistent reaction in the body that causes ongoing harm. Researchers now believe that this reaction is an immune process known as the inflammatory response. The following is one theory about how the inflammatory response contributes to heart disease:

The injuries to the arteries during oxidation signal the immune system to release white blood cells (particularly those called neutrophils and macrophages) at the site. These factors initiate the inflammatory response.
Macrophages literally "eat" foreign debris, in this case oxidized LDL cholesterol.
The process converts LDL cholesterol into foamy material that attaches to the smooth muscle cells of the arteries. The cholesterol becomes mushy and accumulates on artery walls.
Over time the cholesterol dries and forms a hard plaque, which causes further injury to the walls of the arteries.
In response to this additional harm, the immune system releases other factors called cytokines. These are powerful inflammatory molecules that attract more white blood cells and perpetuate the whole cycle, causing persistent injury to the arteries.

Click the icon to see an image of atherosclerosis.

Evidence is growing that the inflammatory response may be present not only in local plaques in single arteries but also throughout the arteries leading to the heart.

Blockage in the Arteries. Eventually these calcified (hardened) arteries become narrower (a condition known as stenosis).

As this narrowing and hardening process continues, blood flow slows and prevents sufficient oxygen-rich blood from reaching the heart.
Such oxygen deprivation in vital cells is called ischemia. When it affects the coronary arteries, it causes injury to the tissues of the heart.
Injured inner vessel walls also fail to produce enough nitric oxide, a substance critical for maintaining blood vessel elasticity. (Nitric oxide has complex effects and may increase inflammation in the arteries.)
These narrow and inelastic arteries not only slow down blood flow but also become vulnerable to injury and tears.

Click the icon to see an image of coronary artery blockage

The End Result: Heart Attack. Heart attack can occur as a result of one or two effects of atherosclerosis.

(1) If the artery becomes completely blocked and ischemia becomes so extensive that oxygen-bearing tissues around the heart die.

(2) If the plaque itself develops fissures or tears. Blood platelets adhere to the site to seal off the plaque, and a blood clot (thrombus) forms. A heart attack can then occur if the formed blood clot completely blocks the passage of oxygen-rich blood to the heart.

Click the icon to see an image of the developmental process of atherosclerosis.

Angina is the primary symptom of coronary artery disease and, in severe cases, of a heart attack. It is typically experienced as chest pain and occurs when the heart muscle does not get as much blood (hence as much oxygen) as it needs for a given level of work (ischemia). Angina is usually referred to as one of two states:

Click the icon to see an image about angina.

Stable Angina (which is predictable)
Unstable Angina (which is less predictable and a sign of a more serious situation)

Angina itself is not a disease. Much evidence indicates that onset of angina less than 48 hours before a heart attack may be protective, possibly by conditioning the heart to resist the damage resulting from the attack. Angina may be experienced in different ways and can be mild, moderate, or severe.

Click the icon to see an image of angina.

Specific factors are typically considered in determining whether symptoms indicate angina:

Quality of the pain. Angina pain is typically described by patients as squeezing, heavy, suffocating, or griplike. It is rarely described as stabbing or burning. Changing one's position or breathing in and out does not affect the pain. The intensity of the pain does not always relate to the severity of the medical problem. Some people may feel a crushing pain from mild ischemia, while others might experience only mild discomfort from severe ischemia. In some cases, the patient experiences shortness of breath, fatigue, or palpitations instead of pain. In others, the ischemia is entirely asymptomatic ("silent ischemia").
Duration. A typical angina attack lasts minutes. If it is more fleeting or lasts for hours, it is probably not angina.
Location. Pain is usually in the chest under the breast bone. It often radiates to the neck, jaw, or left shoulder and arm. Less commonly, patients report symptoms that radiate to the right arm or back.
Triggers of Angina. Angina is usually triggered by physical exertion, emotional stress, or exposure to cold.
Factors that Relieve Angina. Angina is usually relieved by rest or by taking nitroglycerine under the tongue.

Stable Angina. Stable angina is predictable chest pain. Although less serious than unstable angina, it can be extremely painful. It is usually relieved by rest and responds well to medical treatment (typically nitroglycerin). Any event that increases oxygen demand can cause an angina attack. Some typical triggers include:

Exercise
Cold weather
Emotional tension
Large meals

Angina attacks can occur at any time during the day, but most occur between 6 a.m. and noon.

Unstable Angina and Acute Coronary Syndrome. Unstable angina is a much more serious situation and is often an intermediate stage between stable angina and a heart attack, in which an artery leading to the heart (a coronary artery) becomes completely blocked. A patient is usually diagnosed with unstable angina under one or more of the following conditions:

Pain awakens a patient or occurs during rest.
A patient who has never experienced angina has severe or moderate pain during mild exertion (walking two level blocks or climbing one flight of stairs).
Stable angina has progressed in severity and frequency within a 2-month period, and medications are less effective in relieving its pain.

Unstable angina is now usually discussed as part of a condition called acute coronary syndrome (ACS). ACS also includes people with a condition called NSTEMI (non ST-segment elevation myocardial infarction) -- also referred to as non-Q wave heart attack. With NSTEMI, the blood tests suggest a developing heart attack. These conditions are less severe than heart attacks but may develop into full-blown attacks without aggressive treatment. [See In-Depth Report #12: Heart attack and acute coronary syndrome.]

Prinzmetal's Angina. A third type of angina, called variant or Prinzmetal's angina, is caused by a spasm of a coronary artery. It almost always occurs when the patient is at rest. About two-thirds of people with it have severe atherosclerosis in at least one major blood vessel. Irregular heartbeats are common, but the pain is generally relieved immediately with standard treatment.

Click the icon to see an image of a coronary artery spasm.

Silent Ischemia. Some people with severe coronary artery disease do not experience angina pain. This condition is known as silent ischemia, which some experts attribute to abnormal processing of heart pain by the brain. This is a dangerous condition because patients have no warning signs of heart disease. Some studies suggest that people with silent ischemia experience higher complication and mortality rates than those with angina pain. (Angina pain may actually protect the heart by conditioning it before a heart attack.)

Syndrome X. Syndrome X is a condition that occurs when patients have atypical angina chest pain. Their electrocardiograms are abnormal during a stress test, but they have no signs of blocked arteries. It is more likely to occur in women. Although it unclear what causes this condition, imaging tests suggest that Syndrome X may also be caused by ischemia, as is angina.

Prognosis

According to a 2007 report, nearly 16 million Americans have coronary artery disease. In the U.S., coronary artery disease is the leading killer of both men and women. In 2004, nearly 500,000 people died because of CAD. On the positive side, heart attack mortality rates have been declining. Half of men and 63% of women who die of heart disease do not have angina or other warning symptoms prior to their fatal attacks. Although at this time no tests can reliably predict whether a heart attack will occur, experts estimate that up to 30% of fatal attacks and many follow-up surgeries could be avoided with healthy lifestyle changes and by sticking to medical treatments. Two-thirds of patients who have suffered a first heart attack, however, do not take the necessary steps to prevent another.

The following syndromes suggest different degrees of severity among patients with heart disease.

Stable Angina. This condition can usually be managed with lifestyle measures and medications, such as low-dose aspirin. The more severe the angina, however, the greater the chance for progressing to a more serious condition.

Acute Coronary Syndromes (ACS). ACS includes severe and sudden heart conditions that require aggressive treatment but have not developed into a full-blown heart attack. ACS refers to either unstable angina or NSTEMI (non ST-segment elevation myocardial infarction). NSTEMI is also known as non Q-wave myocardial infarction.

Angina is a specific type of pain in the chest caused by inadequate blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).

Unstable angina is potentially serious and chest pain is persistent, but blood tests do not show markers for heart attack.
With NSTEMI, the blood tests suggest a developing heart attack, but, most likely, injury in the arteries is less serious than with a full-blown heart attack.

Most discussions of the treatment of unstable angina now refer to acute coronary syndrome. Doctors use the presence of a number of factors to help predict which ACS patients are most at risk for developing a heart attack.

First, patients are categorized by whether they have a history of heart disease or risk factors for heart disease (such as diabetes, high blood pressure, peripheral artery disease) or other complicating conditions (such as lung disease, heart failure). The doctor also evaluates the severity of the angina. Other factors that pose a high risk for ACS include:

Age 65 years or older
Evidence of severe heart tissue injury
Having a lighter weight
Having a history of severe chronic angina
Having abnormal lung sounds called rales (a bubbling or crackling sound) on examination
ST-segment deviation
Having either very slow or very fast heat beats
Having very low blood pressure

Heart Attack. A full-blown heart attack occurs with severe damage to the heart, which blocks oxygen.

ANYONE WHO BELIEVES THEY ARE HAVING A HEART ATTACK SHOULD IMMEDIATELY CALL THE EMERGENCY MEDICAL SYSTEM (911 IN THE UNITED STATES).

People with known heart disease and any unusual chest pain or other symptoms of heart attack that do not clear up with medications should go to the hospital. The degree of pain and the specific symptoms before a heart attack vary greatly among individuals. Symptoms can be abrupt, gradual, or intermittent.

Chest Pain. People with heart disease or risk factors should be concerned about any chest pain, usually precipitated by exercise or stress, that interrupts normal activities and does not clear up after resting or taking angina medications. Chest symptoms might be experienced as follows:

Pain is typically felt as a crushing weight against the chest, accompanied by profuse sweating. The pain may radiate to the left shoulder and arm, the neck or jaw, and even infrequently to the right arm. The arm may be tingling or numb.
Some people may have only a tingling sensation or a sense of fullness, squeezing, or pressure in the chest.
In some patients with a history of heart disease, chest pain is mild. Such patients may have experienced unexplained fatigue, depression, and ill health within a month of a heart attack. Although chest pain is the classic symptom, it occurs in only about half of patients with a heart attack.

Other Common Symptoms.

Nausea, vomiting, and cold sweats
A feeling of indigestion or heartburn
Fainting
A great fear of impending death, a phenomena known as angor animi

Atypical Symptoms. Some studies suggest that nearly half of patients with heart attack do not have chest pain as the primary symptom. Common atypical symptoms of a heart attack include:

Shortness of breath
Cardiac arrest
Dizziness, weakness, and fainting
Abdominal pain

Patients most likely to have atypical symptoms are women and the very elderly (although they can certainly have classic heart attack symptoms as well).

In one study, 52% of elderly people with acute coronary syndrome had atypical symptoms that included shortness of breath, nausea, profuse sweating, pain in the arms, and fainting. Such symptoms were more likely to occur in people with personal or family history of heart disease.
Before a heart attack, women are more likely than men to be nauseous and experience pain high in the abdomen or chest. Their first symptom may be extreme fatigue after physical activity rather than chest pain. Chest pain in women is also more likely to be caused by non-heart problems than in men.

Symptoms That Are Less Likely to Indicate a Heart Attack. The following symptoms are less likely to be due to a heart attack:

Sharp pain brought on by lung movements or coughing
Pain that is mainly or only in the middle or lower abdomen
Pain that can be pinpointed with the top of one finger
Pain that can be reproduced by moving or pressing on the chest wall or arms
Pain that is constant and lasts for hours (although no one should wait hours if they suspect they are having a heart attack)
Pain that is very brief and lasts for a few seconds
Pain that spreads to the legs

However, the presence of these symptoms does not always rule out a serious heart event.

Chest pain is a very common symptom in the emergency room, but heart problems account for only 10 - 33% of all episodes.

The most common causes of chest pain are muscular and bone problems. Problems affecting the ribs and chest muscles include injured muscles, fractures, arthritis, spasms, and infections.

Other causes of chest pain include:

Anxiety attacks
Gastrointestinal disorders (gallstone attacks, peptic ulcer disease, hiatal hernia, heartburn)
Asthma
Spasm in the coronary artery
Abnormalities of the heart muscle
Rupture of the aorta
Collapsed lung
Acute inflammation of the heart
Blood clot in the lung
High thyroid levels (hyperthyroidism)
Anemia
Vasculitis (a group of disorders that cause inflammation of the blood vessels)
Exposure to high altitudes (rare)

Individuals who experience symptoms of a heart attack should take the following actions:

For angina patients, take one nitroglycerin dose either as an under-the-tongue tablet or in spray form at the onset of symptoms. Take another dose every 5 minutes up to three doses or when the pain is relieved, whichever comes first.
Call 911 or the local emergency number. This should be the first action taken if angina patients continue to experience chest pain after taking the full three doses of nitroglycerin. However, only 20% of heart attacks occur in patients with long-standing angina. Therefore, anyone who has heart disease or risk factors for it and experiences heart attack symptoms should contact emergency services.
The patient should chew an aspirin (250 - 500 mg) and be sure that emergency health providers are informed of this so an additional dose is not given.
Patients with chest pain should go immediately to the nearest emergency room, preferably traveling by ambulance. They should not drive themselves.

Click the icon to see an image about heart attack symptoms.

Click the icon to see another image about heart attack symptoms.

Risk Factors

Over 13 million Americans have had angina, a heart attack, or both. Each year, about 1.2 million people will experience a serious heart event. About 25% of all Americans have one or more risk factors for heart disease. Most risk factors for heart disease are related to lifestyle and environmental factors.

Over the past decades, heart disease rates declined in both men and women as they quit smoking and improved dietary habits. This rate, however, has stabilized in recent years, most likely because of the dramatic increase in obesity in the U.S. and other industrialized nations. There have also been minimal changes in other risk factors, including smoking, sedentary behavior, and blood pressure control. Some risk factors cannot be changed, including age, gender, and genetics. Nevertheless, their effects can still be modified with healthy lifestyle changes.

Heart disease may be prevented with a healthy diet and regular exercise, and by quitting smoking if you smoke. Follow your health care provider's recommendations for the treatment and prevention of heart disease.

The American Heart Association guidelines for preventing heart disease recommend:

Improve Cholesterol. People with at least two risk factors and a 10-year risk for heart disease or stroke of more than 20% should aim for LDL levels of less than 100 mg/dl. Statins are now used in more cases.

Keep Blood Pressure Low. People in normal health should have a blood pressure reading of 120/80 mm Hg or less. According to the latest guidelines, blood pressure readings of 120/80 are considered normal, readings of 140/90 or higher indicate hypertension, and readings in between the two are called pre-hypertension. Patients with diabetes or chronic kidney disease should maintain blood pressure readings of 130/80 mm Hg or less, while others should be no higher than 140/90 mm Hg.

Exercise. Everyone in normal health should engage in at least moderate physical activity for a minimum of 30 minutes on most, if not all, days of the week.

Healthy Diet. Everyone should aim for a diet that contains a healthy balance of fruits, vegetables, grains, fish, nuts, legumes, poultry, lean meat, and low-fat dairy items. Avoid saturated fats and trans-fatty acids.

Quit Smoking. Also avoid exposure to secondhand smoke.

Maintain Weight. People should aim for a BMI index of 18.5 - 24.9.

Taking Aspirin. People whose risk for heart disease within 10 years is 10% or more should take a low-dose aspirin every day, unless they have medical reasons to avoid aspirin.

Control Diabetes. People with diabetes should aim for fast blood glucose levels of less than 110 mg/dl and hemoglobin A1C or less than 7%.

Control Atrial Fibrillation. People with atrial fibrillation should use anticoagulants to reduce the risk for blood clots.

Age. About 85% of people who die from heart disease are over the age of 65.

Gender. Coronary artery disease and heart attacks are much more common in middle-aged men. Women have, on average, 10 - 15 more years of heart disease-free life than do men, but as women age, they catch up to men. Women, in fact, are more likely to have angina than men. Younger women with heart disease often do not have the same symptoms as their male counterparts and may be less likely to be diagnosed correctly. They are also more likely than men to die after a heart attack.

In 2007, the American Heart Association issued updated guidelines focusing on prevention of heart disease in women. The new guidelines recommend:

Healthy diet (fresh fruits and vegetables, low-fat dairy products, salt and saturated fat restrictions, alcohol moderation)
Eating oily fish (such as salmon) at least twice a week. Women with existing heart disease should consider taking fish oil supplements of 850 – 1,000 mg eicosapentaenoic acid (EPA) and docosahexaenoic acid (DPA).
Increased physical activity (60 – 90 minutes, preferably 7 days a week)
Quitting smoking
Low-dose aspirin therapy for all women age 65 years and older who can safely take aspirin. High-risk women may require 75 – 325 mg / day; lower-risk women may benefit from 81 mg a day or 100 mg every other day.

Genetic Factors. Genetics are involved in increasing the likelihood of developing important risk factors such as diabetes and high blood pressure. For example, one genetic variant called apolipoprotein E4 (ApoE4) affects cholesterol levels, particularly those associated with heart disease.

Ethnicity. African-American women face the highest risk for death from heart disease, and their rate of heart attacks is increasing. (Mortality rates in men do not differ much by race.) Native American men have a lower risk for heart disease than Caucasian men, and Hispanics have the lowest risk for heart disease of all major American population groups.

African-Americans face a number of biologic and social dangers to their hearts.

They have a higher prevalence of diabetes and hypertension than do Caucasians.
They tend to have poorer diets, higher stress levels, and less access to health care.
All African-Americans risk discrimination in obtaining optimal treatments, but women may be at particular risk for unequal treatment. In one study in which female actors portrayed heart patients, African-American women were 60% less likely to receive aggressive (and expensive) diagnostic tests than African-American men or any Caucasians, even though they presented with similar symptoms.
While African-Americans comprise 13% of the U.S. population, African-Americans have comprised only 2 - 9% of subjects in most major research trials, so knowledge about their specific risks is limited.
Some African-Americans with coronary artery disease appear to have a genetic trait that increases the danger of triglycerides, which may be particularly hazardous for women.

Click the icon to see an image about ethnicity and heart disease risks.

Cholesterol. In spite of its bad press, cholesterol is an essential nutrient necessary for many cellular functions. However, when certain cholesterol levels rise in the blood, they can have dangerous consequences, depending on the type of cholesterol. Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol responsible for many heart problems. Triglycerides are another type of lipid (fat molecule) that can be bad for the heart. High-density lipoprotein (HDL) cholesterol is the "good" cholesterol that helps protect against heart disease. Doctors test for a "total cholesterol" profile that includes measurements for LDL, HDL, and triglycerides. The ratio of these lipids can affect heart disease risk.

For example, according to one study, men with total cholesterol levels over 240 mg/dl have a risk that is two to four times higher than men whose cholesterol is below 200. A number of studies have demonstrated that reducing LDL and total cholesterol levels and boosting high-density lipoprotein (HDL) levels can improve survival and prevent heart attacks in people with and without heart disease.

It is very difficult to measure LDL levels by themselves, but LDL levels can be reliably calculated by the Friedewald formula: LDL=TC-HDL-TG/5. (LDL=low-density lipoprotein; TC= total cholesterol; HDL=high-density lipoprotein; TG=triglycerides.)

Click the icon to see an image about serum cholesterol.

Cholesterol Goals. In 2004, the National Cholesterol Education Program updated its clinical practice guidelines. The new recommendations set lower treatment goals for LDL levels based on a patient's risk factors for heart disease.

These risk factors include:

Having a first-degree female relative diagnosed with heart disease before age 65 or a first-degree male relative diagnosed before age 55
Being male and over age 45 or female and over age 55
Cigarette smoking
Diabetes
High blood pressure
Metabolic syndrome (risk factors associated with obesity such as low HDL levels and high triglycerides

Having two or more of these risk factors indicates a greater than 20% chance of having a heart attack within 10 years.


Risk Level	Goal (d/L)	Optimal Goal(d/L)
Very High Risk	70	70
High Risk	100	70
Moderate Risk	130	100
Low Risk	160	130

LDL cholesterol, together with other risk factors for heart disease, is the best determinant for whether cholesterol therapy is needed and whether it is working properly. In particular, the new guidelines emphasize lower LDL levels and earlier treatment for people with coronary artery disease, or other forms of atherosclerosis, and diabetes.


Total Cholesterol Goals	LDL Goals	HDL Goals	Triglyceride Goals
Less than 200 mg/dL is desirable. Between 200 and 239 is borderline. Over 240 is high.	70 mg/dL or less is the new goal for very high-risk patients (recent heart attack; current active or unstable cardiovascular or cerebrovascular disease; or two multiple risk factors as defined above.) Below 100 mg/dl is optimal for everyone. It should be the goal for high-risk people including those with existing heart disease, diabetes, or two or more risk factors for heart disease; 70 mg/dL is an optimal goal for these individuals. 130 mg/dl or below for people with two or more risk factors; 100 mg/dL is the optimal goal. 160 mg/dl or less for people at less risk (one or zero risk factors); 130 mg/dL is the optimal goal. Anything over 160 is high with levels over 190 being very high. LDL levels over 190 require medication even with no other cardiac risk factors present.	Levels above 40 mg/dL are desirable; levels above 60 mg/DL are optimal.	Below 150 mg/dL is normal. 150-199 is borderline high. 200-499 is high. Over 500 is very high.
*Risk factors for heart disease include a family history of early heart problems before age 55 for men, before age 65 for women, smoking, high blood pressure, diabetes, being older (over 45 for men and 55 for women), and having HDL levels below 35 mg/dl. People with two or more of these risk factors may have a 10-year risk of heart attack that exceeds 20%, and may therefore need to aim for LDL levels of 100 mg/dL or below.

Other Lipids. Elevated levels of other fatty molecules (lipids) are also now thought to be important indicators of heart disease risk. Studies are finding an elevated risk for angina and first heart attacks in people with elevated levels of lipoprotein(a), or lp(a). This lipoprotein falls somewhere in density between HDL and LDL and may have some properties that increase the risk for blood clots. Some experts suggest, however, that high levels of lp(a) may merely be markers of late-stage atherosclerosis, not a cause.

[See In-Depth Report #23: Cholesterol; and In-Depth Report #43: Heart-healthy diet.]

High blood pressure, or hypertension, has long been a proven cause of coronary artery disease. Blood pressure is categorized as normal, prehypertensive, and hypertensive (which is further divided as Stage 1 or 2 according to severity). High blood pressure is generally considered to be a blood pressure reading greater than or equal to 140 mm Hg (systolic) or greater than or equal to 90 mm Hg (diastolic). Blood pressure readings in the prehypertension category (120 - 139 systolic or 80 - 89 diastolic) indicate an increased risk for developing hypertension. [See Table Blood Pressure Ranges.]

A normal blood pressure reading is 120/80 mm Hg or lower. Most people with high blood pressure should aim for a goal of below 140/90 mm Hg. Patients with certain health problems should aim lower (blood pressure in patients with kidney disease, heart failure, or diabetes should be equal to or lower than 130/80 mm Hg.)

Click the icon to see an image about hypertension.


Blood Pressure Category	Ranges for Most Adults (systolic/diastolic)
Normal Blood Pressure (systolic/diastolic)	Systolic below 120 mm Hg Diastolic below 80 mm Hg
Prehypertension (Formerly Classified as Normal to High-Normal Blood Pressure)	Systolic 120 to 139 mm Hg Diastolic 80 to 89 mm Hg (NOTE: 139/89 or below should be the minimum goal for everyone. People with diabetes or chronic kidney disease should strive for 130/80 or less.)
Mild Hypertension (Stage 1)	Systolic 140 to 159 mm Hg Diastolic 90 to 99 mm Hg
Moderate-to-Severe Hypertension (Stage 2)	Systolic over 160 mm Hg and/or Diastolic over 100 mm Hg
Note: If one of the measurements is in a higher category than the other, the higher measurement is usually used to determine the stage. For example, if systolic pressure is 165 (Stage 2) and diastolic is 92 (Stage 1), the patient would still be diagnosed with Stage 2 hypertension. A high systolic pressure should be a major focus of concern in most adults.

American obesity is at epidemic levels in all age groups. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels are usually high while HDL (beneficial cholesterol) levels tend to be low, both risk factors for heart disease. Obesity has other effects (hypertension, increase in inflammation) that pose major risks to the heart.

Click the icon to see an image of childhood obesity.

Obesity is particularly hazardous when it is one of the components of the metabolic syndrome. This syndrome is diagnosed when three of the following are present: abdominal obesity, low HDL cholesterol, high triglyceride levels, high blood pressure, and insulin resistance. Metabolic syndrome is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. A 2002 study estimated that 24% of the population now has this condition. Obesity is highly linked with type 2 diabetes, and diabetes itself poses a significant risk for high cholesterol levels and heart disease.

Some obese patients with coronary artery disease may consider having bariatric surgery (stomach bypass) to lose excess weight. The weight lost after surgery can help improve blood pressure, cholesterol, blood sugar and other factors associated with CAD. A 2005 study reported that bariatric surgery is safe for patients with CAD who cannot lose weight with diet and exercise, which should always be tried first.

[See In-Depth Report #53: Weight control and diet.]

People who are sedentary are almost twice as likely to suffer heart attacks as are people who exercise regularly. Exercise has a number of effects that benefit the heart and circulation, including:

Improving cholesterol and lipid levels
Reducing inflammation in the arteries
Assisting weight loss programs
Helping to keep blood vessels flexible and open

Studies continue to show that physical activity and avoiding high-fat foods are the two most successful means of reaching and maintaining heart healthy levels of fitness and weight.

Experts have been attempting to define how much exercise is needed to produce heart benefits. In 2002, a well-conducted study on overweight adults confirmed previous research that reported beneficial changes in cholesterol and lipid levels even when people performed low amounts of moderate or high intensity exercise (walking or jogging 12 miles a week). However, more intense exercise is required to significantly change cholesterol levels, notably by increasing HDL (the so-called good cholesterol). Overweight people who have trouble losing pounds can still achieve considerable heart benefits by exercising. Resistance (weight) training has also been associated with heart protection. Exercises that train and strengthen the chest muscles may prove to be very important for patients with angina.

Click the icon to see an image about exercise.

Click the icon to see an image about hypertension and lifestyle changes.

Some studies suggest that for the greatest heart protection, it is not the duration of a single exercise session that counts but the total daily amount of energy expended. Therefore, the best way to exercise may be in multiple short bouts of intense exercise, which can be particularly helpful for older people.

Sudden strenuous exercise (such as snow shoveling and mowing lawns) puts many people at risk for angina and heart attack. Activities that involve raising the arms above the head may also be risky. Patients with angina should never exercise shortly after eating. People with risk factors for heart disease should seek medical clearance and a detailed exercise prescription. And all people, including healthy individuals, should listen carefully to their bodies for signs of distress as they exercise. [See In-Depth Report #29: Exercise.]

Heart disease and stroke are the leading causes of death in people with diabetes. People with diabetes are at risk for the following heart-risk conditions, and the more of these conditions they have, the worse the outlook.

High blood pressure (hypertension). Up to 75% of cardiovascular problems in people with diabetes may be due to hypertension.
Very unhealthy cholesterol and lipid balances (high triglyceride levels and lower HDL).
Blood clotting problems.
Impaired nerve function (neuropathy), which can also damage the heart. Some experts estimate that the mortality rates from neuropathy-related heart conditions range from 15 - 53%.

People with both diabetes and heart disease may have a higher risk for silent ischemia, a condition in which people have blocked arteries but do not experience the angina, the chest pain that signals heart disease. [See In-Depth Report #9: Diabetes - type 1; or In-Depth Report #60: Diabetes - type 2.]

Peripheral artery disease (PAD) occurs when atherosclerosis affects the extremities, particularly the feet and legs. The major risk factors for heart disease and stroke are also the most important risk factors for PAD. (The combination of such conditions with PAD also produces more severe forms of heart or circulatory disease.) Although signs of heart disease are detected in only 20 - 40% of patients with PAD after an initial diagnosis, studies suggest that when intense heart-diagnostics tests are performed, such as angiography or thallium stress tests, co-existing heart disease is detected in up to 90% of all PAD patients. [See In-Depth Report #102: Peripheral artery disease.]

Smokers in their 30s and 40s have a heart-attack rate that is five times higher than their nonsmoking peers. Cigarette smoking may be directly responsible for at least 20% of all deaths from heart disease, or about 120,000 deaths annually. Smoking cigars may increase the risk of early death from heart disease, although evidence is much stronger for cigarette smoking. Although heavy cigarette smokers are at greatest risk, a 2002 study suggested that people who smoke as few as three cigarettes a day are at higher risk for blood vessel abnormalities that endanger the heart. Regular exposure to passive smoke also increases the risk of heart disease in nonsmokers. [See In-Depth Report #41: Smoking.]

Eating habits can be protective or dangerous to the heart. Avoiding saturated fats and trans-fatty acids is particularly important for controlling cholesterol.

Diet plays an important role in the health of the heart. In 2006, the American Heart Association (AHA) issued revised diet and lifestyle recommendations. The current guidelines recommend:

Balance calorie intake and physical activity to achieve or maintain a healthy body weight. (Controlling weight, quitting smoking, and exercising regularly are essential companions of any diet program. Try to get at least 30 minutes, and preferably 60 – 90 minutes, of daily exercise.)
Consume a diet rich in a variety of vegetables and fruits. Vegetables and fruits that are deeply colored (spinach, carrots, peaches, berries) are especially recommended as they have the highest micronutrient content.
Choose whole-grain, high-fiber foods. These include fruits, vegetables, and legumes (beans). Good whole grain choices include whole wheat, oats/oatmeal, rye, barley, brown rice, buckwheat, bulgur, millet, and quinoa.
Consume fish, especially oily fish, at least twice a week (about 8 ounces/week). Oily fish such as salmon, mackerel, and sardines are rich in the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Consumption of these fatty acids is linked to reduced risk of sudden death and death from coronary artery disease.
Limit daily intake of saturated fat (found mostly in animal products) to less than 7% of total calories, trans fat (found in hydrogenated fats, commercially baked products, and many fast foods) to less than 1% of total calories, and cholesterol (found in eggs, dairy products, meat, poultry, fish, shellfish) to less than 300 mg per day. Choose lean meats and vegetable alternatives (such as soy). Select fat-free and low-fat dairy products. Grill, bake, or broil fish, meat, and skinless poultry.
Use little or no salt in your foods. Reducing salt can lower blood pressure and decrease the risk of heart disease and heart failure.
Cut down on beverages and foods that contain added sugars (corn syrups, sucrose, glucose, fructose, maltrose, dextrose, concentrated fruit juice, honey.)
If you consume alcohol, do so in moderation. The AHA recommends limiting alcohol to no more than 2 drinks per day for men and 1 drink per day for women.

[See In-Depth Report #43: Heart-healthy diet.]

Stress. The effects of mental stress on heart disease are controversial. Stress can affect the heart when it activates the sympathetic nervous system (the automatic part of the nervous system that affects many organs, including the heart). Some studies suggest an association between acute stress and a higher risk for serious cardiac events, such as heart rhythm abnormalities and heart attacks, in people with heart disease. However, not all studies report strong evidence that stress has any effect on the heart, particularly in people without any history of heart disease. [See In-Depth Report #31: Stress.]

Depression. Depression increases the severity of heart attack and may even worsen a patient's response to medication for heart disease. Although people with heart disease may become depressed, this does not explain entirely the link between the two problems. Data suggest that depression itself may be a risk factor for heart disease as well as its increased severity.

A number of studies indicate that depression has biologic effects on the heart, including blood clotting and heart rate. One study, for example, reported an association between depression and a greater risk for death from heart problems even in people without a history of heart disease. Even mild depression, which includes feelings of hopelessness experienced over many years, may harm the heart. A 2007 study suggested that depressive symptoms (fatigue, loss of appetite) may be a sign of thickening arteries, the early stage of coronary artery disease. [See In-Depth Report #8: Depression.]

Benefits of Moderate Drinking. Several studies have found heart protection from moderate intake of alcohol (one or two glasses a day). Moderate alcohol consumption can help boost HDL levels. Alcohol may also prevent blood clots and inflammation. Although red wine is most often cited for healthful properties, any type of alcoholic beverage appears to have similar benefit.

Adverse Effects of Heavy Drinking. By contrast, heavy drinking harms the heart. In fact, heart disease is the leading cause of death in alcoholics. Evidence suggests that people who consume more than three drinks a day have abnormal blood clotting factors. Heavy alcohol consumption can raise blood pressure, and binge drinking may increase the risk for hemorrhagic stroke (caused by bleeding in the brain). Large doses of alcohol can trigger irregular heartbeats, which can be dangerous in people with existing heart disease.

Pregnant women and people who can't drink moderately should not drink at all.

Homocysteine and Vitamin B Deficiencies. Deficiencies in the B vitamins folate (known also as folic acid), B6, and B12 have been associated with a higher risk for heart disease in some studies. Such deficiencies produce higher blood levels of homocysteine, an amino acid that has been associated with a higher risk for heart disease, stroke, and heart failure. Researchers have been studying whether vitamin B supplements can reduce homocysteine levels and, consequently, heart disease risks.

Several major 2006 studies indicated that while B vitamin supplements do help lower homocysteine levels, they have no effect on heart disease outcomes. The studies, published in the New England Journal of Medicine, examined patients who had either recently had a heart attack or suffered from diabetes or heart disease. Results showed a similar number of heart attacks and strokes among patients who took B vitamins and those who received placebo. Some experts think that homocysteine may be a marker for heart disease rather than a cause of it.

Click the icon to see the benefits of vitamin B.

Click the icon to see the food sources of vitamin B.

C-Reactive Protein. C-reactive protein is a product of the inflammatory process. Evidence increasingly suggests that high levels may predict future heart disease. It is not known if the protein plays any causal role or whether it is simply a marker for other factors in the disease process.

C. pneumoniae and Other Infectious Organisms. Some microorganisms and viruses have been under suspicion for triggering the inflammation and damage in the arteries that contribute to heart disease. The strongest evidence to date supports a possible role from Chlamydia (C.) pneumoniae (a non-bacterial organism that causes mild pneumonia in young adults). C. pneumoniae has been detected in plaques in the arteries of patients with heart disease. In some studies, evidence of previous infection has been associated with a higher risk for heart events.

Other studies also suggest that cytomegalovirus (CMV), a common virus, may have similar effects. Many people, however, have been infected with these organisms, and no clear association has been found with any of these infections.(H. pylori, the bacteria that causes peptic ulcers, has also been studied for heart effects, but evidence is very weak on any link.)

Erectile Dysfunction. Recent research suggests that erectile dysfunction may be a warning sign of coronary artery disease, even in men who are not considered at risk for the condition. Some studies indicate that men with erectile dysfunction have higher levels of C-reactive protein and more symptoms of atherosclerosis than men without erectile problems.

Periodontal Disease. A number of studies support an association between periodontal disease and cardiovascular disorders. According to a 2003 major analysis, periodontal (gum) disease is associated with a 20% higher risk for ischemic stroke and heart disease. (The added risk may be even higher in adults under 65.) Recent evidence is pointing to the inflammatory response as the common element.

Click the icon to see an image of gum disease.

Anemia. Anemia has adverse effects on the heart and increases the severity of cardiac conditions, including heart failure and heart attacks. A 2002 study suggested that anemia may even be a risk factor for heart disease itself. Blood transfusions after a heart attack improve survival rates in elderly patients who are anemic.

Iron Overload. An inherited disease called hemochromatosis, in which the intestinal tract absorbs too much iron from food, has been associated with atherosclerosis and heart attack. About 10% of Caucasians carry the gene for this condition. There is no strong evidence that excess iron levels in people without hemochromatosis can contribute to heart disease.

Sleep Apnea. Obstructive sleep apnea is a condition in which tissues in the upper throat collapse at intervals during sleep, thereby blocking the passage of air. It has been strongly associated with high blood pressure and obesity, but is also associated with heart disease and heart attacks, regardless of these risk factors. Some evidence suggests that obstructive apneas cause an increase in stiffness and inflammation in the arteries.

Some inborn or natural conditions are not risk factors themselves but have been associated with a higher incidence of heart disease or its consequences:

Factors Before Birth and In Infancy. Low weight at birth and in the womb has been associated with later heart disease in a few studies. Some suggest, however, that this may just reflect poor nutrition in the mother, which appears to affect life-long risk.

Seasonal Differences. More deaths from heart disease occur in December and January, and the fewest in the summertime. Although lower temperatures and snow shoveling may play a role in some cases, more winter deaths have been reported even in warm regions. Holiday stress or fewer daylight hours have been suggested as other reasons for these higher winter rates.

Physical Characteristics. Male pattern baldness, hair in the ear canals, and creased earlobes are associated with a higher risk for heart disease in Caucasian males.

Click the icon to see an image of an ear lobe crease.

Diagnosis

Many tests can diagnose possible heart disease. The choice of which (and how many) tests to perform depends on the patient's risk factors, history of heart problems, and current symptoms. Usually the tests begin with the simplest and may progress to more complicated ones.

Doctors routinely check for high blood pressure and unhealthy cholesterol levels in all older adults. Specific tests are also important in people who may have risk factors or symptoms of diabetes. Doctors may also test for homocysteine, the protein albumin, and blood clotting factors, especially fibrinogen.

An electrocardiogram (ECG) measures and records the electrical activity of the heart. Between 25 - 50% of people who suffer from angina or have silent ischemia, however, have normal ECG readings. The waves measured by the ECG correspond to the contraction and relaxation pattern of the different parts of the heart. Specific waves seen on an ECG are named with letters:

The electrocardiogram (ECG, EKG) is used extensively in the diagnosis of heart disease, from congenital heart disease in infants to myocardial infarction and myocarditis in adults. Several different types of electrocardiogram exist.

P. The P wave is associated with the contractions of the atria (the two chambers in the heart that receive blood from outside).
QRS. The QRS is a series of waves associated with ventricular contractions. (The ventricles are the two major pumping chambers in the heart.)
T and U. These waves follow the ventricular contractions.

The most important wave patterns in diagnosing and determining treatment for heart disease and heart attack are called ST elevations and Q waves.

A depressed or horizontal ST wave suggests some blockage and the presence of a heart disease, even if there is no angina present. (This finding, however, is not very accurate, particularly in women, and can occur without heart problems).
ST elevations and Q waves are the most important wave patterns in diagnosing and determining treatment for a heart attack. They suggest that an artery to the heart is blocked, and that the full thickness of the heart muscle is damaged. ST segment elevations do not always mean the patient has a heart attack. And, some heart attack patients do not have elevated ST segments. Other factors are important in making a diagnosis.

The primary value of exercise stress tests is not to detect coronary artery disease but to help determine the severity and predict the outcome of an existing heart condition. It is considered for the following people:

Patients with possible or probable angina and low or intermediate risk for adverse heart events.
Selected adults who do not have symptoms of heart disease but are at moderate risk to high risk for developing heart disease (a 10 - 20% chance within 10 years). Moreover, heart blockage without angina (silent ischemia) may suggest a more severe condition, at least in men.

Basic Procedure. A stress test (exercise tolerance test) monitors the patient's heart rhythms, blood pressure, and clinical status. It can tell how well the heart handles work and if parts of the heart have decreased blood supply. A typical stress test involves:

The patient walks on a treadmill or rides a stationary bicycle. Exercise continues until the heart is beating at least 85% of its maximum rate, until symptoms of heart trouble occur (changes in blood pressure, heart rhythm abnormalities, angina, fatigue), or the patient simply wants to stop.
For patients who cannot exercise, the doctor may administer dobutamine or arbutamine, which are drugs that simulate the stress of exercise.
An ECG is used to monitor heart rhythms during a stress test. (An echocardiogram or more advanced imaging technique may also be used to visualize the actions of the heart and blood flow.)

More than 25% of patients stop exercising before they reach their own maximum limits because of fear of a heart event. Patients should be reassured that the activities performed in the test under the guidance of a professional are safe.

Interpreting Results. To accurately assess heart problems, experts look at a number of findings derived from the ECG and other tools during exercise. They include:

Exercise capacity. This is a measure of a person's capacity to reach certain metabolic rates.
Heart rate and ST waves. On ECGs, doctors specifically look for abnormalities in part of the wave tracing called an ST segment. A certain type of ST segment depression may suggest the presence of heart disease. However, gender, drugs and other medical conditions can affect the ST segment. Using a measurement that adjusts the ST segment to heart rate improves accuracy.
Dukes Treadmill Score. This important score uses the number of minutes a patient can exercise and other factors that are present in patients with exercise-limiting angina.
Heart rate recovery.
Chronotropic index. This is the percentage of the heart-rate reserve that is used during the exercise. A result of 80% or less suggests a significant risk for serious heart problems in most patients.
Changes in systolic blood pressure.

Using these and other measures, doctors can determine risk fairly accurately, particularly for men of any age with chronic stable angina. The test has limitations, however, and some are significant. For example, a 2002 study indicated that in patients with suspected unstable angina the chances for a future adverse heart event remain high even if the exercise test shows low risk. In addition, for many reasons, the test is less accurate in women, and an echocardiogram may be a more accurate procedure for them. About 10% of patients, particularly younger people, will have false positive test results. In such cases, test results indicate abnormalities when there are no heart problems.

An echocardiogram is a noninvasive test that uses ultrasound images of the heart. This test is more expensive than an ECG, but it can be very valuable, particularly when used with a stress test, to detect the location and extent of heart muscle damage. It appears to be more accurate for women than ECG stress tests, but at this time it is not routinely recommended as a replacement for most women.

Computed tomography (CT) scans used alone or with ECG may be used to detect calcium deposits on the arterial walls, which are strong indicators of current and future coronary artery disease. The presence of calcium does not always signify narrowing of the arteries. But, the absence of calcification in the arteries indicates the patient has no risk for heart disease.

Advanced CT techniques are improving accuracy:

Click the icon to see an image of a CT scan.

Electron Beam Computed Tomography. Electron beam computed tomography (EBCT) is a CT technique that scans the heart so quickly that the motion of the heart appears frozen. This procedure identifies calcification and stratifies cardiac risk accurately.
Multidetector Computed Tomography. Another CT technique called multidetector computed tomography (MDCT) is able to take pictures of the entire heart in 1 millimeter slices in the time it takes for a patient to hold one breath. A 2006 study indicated that MDCT tends to have a high “false-positive” rate (indicating disease when it is not actually there), but for some patients the test may be helpful in ruling out coronary artery disease.

Some expert groups recommend CT scans in selected patients who have an intermediate risk (10 - 20% chance of heart disease within 10 years). For some of these patients, EBCT may be preferred over exercise stress testing, but most experts recommend a stress test as the main diagnostic tool. In general, the use of these expensive imaging tests is probably not very helpful for people at low or high risk. (For people with high risk, the additional information from these tests would not add much value.) More research is needed to determine the benefits of CT scanning in specific individuals.

Radionuclide procedures use imaging techniques and computer analyses to plot and detect the passage of radioactive tracers through the region of the heart. Such tracing elements are typically given intravenously. Radionuclide imaging is useful for diagnosing and determining:

Severity of unstable angina when less expensive diagnostic approaches are unavailable or unreliable
Severity of chronic coronary artery disease
Success of surgeries for coronary artery disease.
Whether a heart attack has occurred

Various imaging techniques may be used with radionuclide procedures, including:

Planar scintigraphy uses a special overhead camera and is the oldest scanning technique.
Single-photon emission computed tomography (SPECT) uses a camera that rotates around the patient and takes pictures of "slices" of the heart. It is more accurate than planar imaging in precisely locating problems in the arteries.
Positron-emission tomographic (PET) scanners employ multiple rings that surround the patients, which detect and record atomic particles (photons) that are emitted by the tracer elements (such as radioactive oxygen, nitrogen, or carbon). It is more expensive and less widely available than SPECT.

Myocardial Perfusion (Blood Flow) Imaging Test (also called the Thallium Stress Test). This radionuclide test is typically used with an exercise stress test to determine blood flow to the heart muscles. It is a reliable measure of severe heart events. It may be useful in determining the need for angiography if CT scans have detected calcification in the arteries. About a minute before the patient is ready to stop exercising, the doctor administers a radioactive tracer into the intravenous line. (Tracers include thallium, technetium, or sestamibi.) Immediately afterwards, the patient lies down for a heart scan, usually with a planar scintigraphy or with SPECT. If the scan detects damage, more images are taken 3 or 4 hours later. Damage due to a prior heart attack will persist when the heart scan is repeated. Injury caused by angina, however, will have resolved by that time.

Radionuclide Angiography. This is a technique for visualizing the chambers and major blood vessels of the heart. It uses an injected radioactive tracer and can be performed during exercise, at rest, or with use of stress-inducing drugs. It is an excellent test for assessing the heart's pumping action and for determining the severity of coronary artery disease. It is an alternative to echocardiograms in certain situations.

Click the icon to see an internal view of the heart.

Magnetic Resonance Angiography (MRA). MRA is a very promising noninvasive imaging technique that can provide three-dimensional images of the major arteries to the heart and identify disease with high accuracy. Experts believe this approach will eventually be a good alternative to angiography.

Click the icon to see an image of a MRI.

Angiography is an invasive test. It is used for patients who show strong evidence for severe obstruction on stress and other tests, and for patients with acute coronary syndrome.

A narrow tube is inserted into an artery, usually in the leg or arm, and then threaded up through the body to the coronary arteries.
A dye is injected into the tube, and an x-ray records the flow of dye through the arteries.
This process provides a map of the coronary circulation, revealing any blocked areas.

Click the icon to see an image of dye in the coronary artery.

Major complications include stroke, heart attacks, and kidney damage. These risks are very low (about 0.1%), however, if the procedure is done in an experienced medical center (one that performs at least 300 of these operations every year). Allergic reactions can also occur. The procedure is expensive, and between 10 - 30% of patients who have this procedure have normal results.

When heart cells become damaged, they release different enzymes and other molecules into the bloodstream. Elevated levels of such markers of heart damage in the blood or urine may help predict a heart attack in patients with severe chest pain and help determine treatment. Some of these factors include:

Troponins. The proteins cardiac troponin T and I are released when the heart muscle is damaged. Both are proving to be among the best diagnostic indications of heart attacks. They help to identify many individuals with ACS who might otherwise be misdiagnosed.
Creatine kinase myocardial band (CK-MB). CK-MB has been a standard marker, but the MB fraction is not as accurate as troponin levels, since elevated levels can appear in people without heart injury.
Myoglobin. Myoglobin is a protein found in heart muscles. It is released early in the injured heart, and it may be useful in combination with CK-MB and the troponins.
Newer biomarkers, including C-reactive protein (CRP), homocysteine, B-type natriuretic peptide (BNP), urinary albumin, and fibrinogen.

Several 2006 studies that evaluated how well biomarkers predict risk of heart events concluded that they do not provide much more useful information than standard risk factors (high blood pressure, unhealthy cholesterol levels, diabetes). At this time, most experts feel that these standard disease risk factors provide the best predictors of the likelihood of developing coronary artery disease, heart attack, or stroke.

Managing Heart Disease

The approach for managing any degree of coronary artery disease involves lifestyle changes. Depending on severity and individual conditions, patients may need one or more medications, surgery, or both.

Healthy diet, regular exercise and quitting smoking if you are a smoker may prevent heart disease. Follow your health care provider's recommendations for treatment and prevention of heart disease.

Experts have come up with a mnemonic device (ABCDE) for remembering 10 factors that are fundamental for management of stable angina and coronary artery disease:

A. Aspirin and anti-angina drugs

B. Blood pressure and beta-blockers

C. Cholesterol-lowering drugs (typically statins) and cigarettes (stopping)

D. Diet and diabetes control

E. Exercise and education

Unstable angina is now usually classified with non-Q myocardial infarction as acute coronary syndrome (ACS) in professional discussions of treatments. ACS usually requires more aggressive treatments, including surgery. [ACS is more fully discussed in In-Depth Report #12: Heart attack and acute coronary syndrome.]

Click the icon to see an image about angina.

Anti-Clotting Medications

Anti-clotting drugs that inhibit or break up blood clots are used at every stage of heart disease. They are generally classified as either antiplatelets or anticoagulants. All anti-clotting therapies carry the risk of bleeding, which can lead to dangerous situations, including stroke.

A thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body. Thrombi or emboli can lodge in a blood vessel and block the flow of blood in that location depriving tissues of normal blood flow and oxygen. This can result in damage, destruction (infarction), or even death of the tissues (necrosis) in that area.

Antiplatelet Drugs. These drugs prevent formation of blood platelets. Platelets are very small disc-shaped blood cells that are important for blood clotting.

Aspirin. Aspirin is an antiplatelet. It is the most common anti-clotting drug. Nearly anyone with existing heart disease or at risk for it is advised to take a low-dose aspirin every day.
Thienopyridines. Clopidogrel (Plavix) and ticlopidine (Ticlid) are thienopyridines, another type of anti-platelet drug.
Glycoprotein IIb/IIIa Inhibitors. These powerful blood-thinning drugs include abciximab (ReoPro, Centocor), eptifibatide (Integrilin), tirofiban (Aggrastat), and lamifiban. They are administered intravenously in the hospital and are used after angioplasty surgery and stent placement.

Click the icon to see an image about blood.

Anticoagulants. Anticoagulants help thin blood and include:

Heparin
Warfarin (Coumadin)
Direct thrombin inhibitors

Aspirin. Aspirin is known as a nonsteroidal anti-inflammatory drug (NSAID). It stops blood platelets, which are major clotting factors, from sticking together to form a blood clot. A daily low-dose aspirin (75 - 325 mg) is usually the first choice for preventing heart disease in high-risk individuals. Aspirin can prevent by 25 – 50% the risk of heart attacks and death in people with existing heart disease and a history of heart attack. It also reduces the risk for stroke. According to a 2006 review, aspirin works equally well for both men and women.

Click the icon to see an image about stomach ulcers.

Side effects from prolonged use of aspirin may include stomach ulcers and bleeding. (There may be a slight increased risk for bleeding-related strokes, which are very uncommon, however. Furthermore, this risk may be outweighed by protection against the more common type of stroke, which is caused by artery blockage.)

Clopidogreland Ticlopidine. Clopidogrel (Plavix) and ticlopidine (Ticlide) are anti-platelet drugs known as thienopyridines. When taken with aspirin, these drugs can significantly reduce the risk for heart attack and stroke in patients with acute coronary syndrome (unstable angina or early signs of heart attack). The combination of aspirin and a thienopyridine is essential for patients who have a drug-eluting stent. According to a 2007 American Heart Association advisory, patients who have a drug-eluting stent must take both aspirin and a thienopyridine for at least 1 year after the stent is inserted. Many experts recommend clopidogrel instead of ticlopidine because ticlopidine has been associated with dangerous blood disorders, particularly thrombocytopenia.

Clopidogrel is also recommended for patients who are undergoing angioplasty. For patients having coronary bypass surgery, it should be withheld for at least 5 -7 days prior to surgery because of a significant bleeding risk. Researchers are investigating whether clopidogrel and aspirin together are better than aspirin alone in reducing the risks following coronary bypass surgery. A 2006 study suggested that for some patients with heart disease, clopidogrel plus aspirin does not work better than aspirin alone for preventing a first heart attack or stroke.

Click the icon to see an image of the developmental process of atherosclerosis.

Click the icon to see an image about atherosclerosis.

Anticoagulants are drugs that prevent or delay blood coagulation and the formation of blood clots. Heparin has been the standard anticoagulant, but a number of drugs are now available that are proving to be better choices in many cases.

Standard (Unfractionated) Heparin. The heparin referred to as unfractionated heparin has been the standard for years and is used alone or in combination with aspirin for managing unstable angina. It is no longer the recommended first choice, however, for this patient group. It must be intravenously administered and monitored with frequent blood tests. The major complication is thrombocytopenia (a severe drop in platelets). This condition is extremely serious and can become life-threatening, particularly with bleeding in various body tissues. Alternatives include low-molecular weight heparin and direct thrombin inhibitors.

Low-Molecular Weight Heparin. Enoxaparin (Lovenox), dalteparin (Fragmin), tinzaparin (Innohep) are drugs known as low-molecular weight heparins (LMWHs). Many doctors now recommend these drugs over standard heparin for patients with unstable angina (unless bypass surgery is being planned). They have similar rates of survival, recurring angina, and bleeding as standard heparin. However, they pose lower risks for heart attack, repeat angioplasties, and thrombocytopenia. They require injections but do not require the ongoing monitoring that standard heparin does. Patients may even be able to self-administer LMWHs as people with diabetes do insulin.

Warfarin. Warfarin (Coumadin) is an oral anticoagulant. It prevents clots by inhibiting vitamin K. Warfarin is used with aspirin after a heart attack to prevent another one and to prevent blood clots in patients with atrial fibrillation. Warfarin is also proving to be more effective than aspirin for preventing heart attacks in patients with acute coronary syndromes. Warfarin therapy poses a dangerous risk for bleeding and blood coagulation must be monitored with frequent blood tests.

Direct Thrombin Inhibitors (DTIs). Direct thrombin inhibitors are a more recent group of anti-coagulants. The first DTI was hirudin, a natural substance derived from the saliva of leeches. New forms include argatroban (Novastan), bivalirudin (Angiomax), danaparoid (Orgaran), lepirudin (Refludan), desirudin (Revasc), and ximelagatran (Exanta). Many of these drugs are used along with warfarin and may be good options for patients who develop thrombocytopenia with heparin use. DTIs may prove to be superior to standard heparin for patients with acute coronary syndrome.

Other Medications

Nitrates have been used in the treatment of angina for over 100 years. These drugs release nitric oxide, thereby relaxing the smooth muscles in blood vessels. Many nitrate preparations are available. The most commonly used are nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates can be absorbed from the gastrointestinal tract (oral tablet), skin (ointment or patch), or from under the tongue (sublingual tablet or spray).

Rapid Acting Nitrates. Rapid-acting nitrates are used to treat acute attacks. Nitroglycerin is the most widely used drug for this purpose. It can be administered under the tongue (sublingually or as a spray) or pocketed between the upper lip and gum (buccally) and can relieve angina within minutes. The procedure for taking nitroglycerin during an attack is as follows:

At the onset of an angina attack, the patient administers one sublingual or buccal tablet or one metered dose of the spray.
If the pain is not relieved within 5 minutes the patient takes a second dose; a third can be taken after another 5 minutes if symptoms persist.
If pain continues after a total of three doses in 15 minutes, the patient should go immediately to the nearest emergency room.

Nitroglycerin is very volatile so its potency can be easily lost. Patients should take the following precautions:

Keep no more than 100 tablets on hand, stored in their original container.
When first opened, the cotton filler should be discarded, and the cap screwed on tightly immediately after each use.
A supply should always be kept close at hand in case of an attack, with the rest kept in a cool dry place.

Intermediate to Long-Term Nitrates. Sublingual tablets of isosorbide dinitrate have a somewhat slower onset of action than nitroglycerin and are useful for preventing exercise angina. Ointments, patches, and oral tablets are used for longer-term prevention of angina attacks:

Transdermal patches are applied in the morning to any hair- or injury-free area on the chest, back, stomach, thigh, or upper arm. Hands should be washed after each patch or ointment application, and sites of application should be rotated to avoid skin irritation.
Nitroglycerin ointment is applied by measuring out an even amount on an applicator paper and then placing, not rubbing or massaging, it on the chest, stomach, or thigh. Any ointment that remains from the previous application should be removed.

Long-acting forms may lose their effectiveness over time, so doctors generally schedule nitrate-free breaks to prevent tolerance. Some concern exists that nitrate-free periods might increase the risk for angina and adverse heart events. One large study, however, found no increased danger when patients used a nitroglycerine patch with scheduled breaks. The use of high blood pressure drugs known as ACE inhibitors may help prevent tolerance to nitrates.

Side Effects. Nitrates have many side effects, some of which can be serious.

Common side effects of nitrates include headaches, dizziness, nausea and vomiting, blurred vision, fast heartbeat, sweating, and flushing on the face and neck. Low blood pressure and dizziness can be relieved by lying down with the legs elevated. These effects are significantly worsened by alcohol, beta-blockers, calcium channel blockers, sildenafil (Viagra), and certain antidepressants. The doctor may prescribe medicines to lessen these side effects. Patients should contact their doctor if these side effects are persistent or severe.

Serious side effects requiring immediate medical help include fever, joint or chest pain, sore throat, skin rash (especially on the face), unusual bleeding or bruising, weight gain, and swelling of the ankles.

Withdrawal. Withdrawal from nitrates should be gradual. Abrupt termination may cause angina attacks.

Beta-blockers are useful for preventing angina attacks and reducing high blood pressure. They reduce the heart's oxygen demand by slowing the heart rate and lowering blood pressure. They are recognized for reducing deaths from heart disease and from heart surgeries, including angiography and coronary bypass. Beta-blockers are the drugs of choice for older patients with stable angina and may also be beneficial for people with silent ischemia. They are, however, less useful for the treatment of Prinzmetal’s angina. Beta-blockers are often prescribed along with other drugs such as nitrates, calcium channel blockers, or statins. A 2006 study suggested that beta-blockers and statins may help stabilize coronary artery disease and prevent the development of heart attacks.

Specific Beta-blockers. Beta-blockers include propranolol (Inderal), carvedilol (Coreg), bisoprolol (Zebeta), acebutolol (Sectral), atenolol (Tenormin), labetalol (Normodyne, Trandate), metoprolol (Lopressor, Toprol-XL), and esmolol (Brevibloc). A nasal spray form of propranolol appears to be very helpful in reducing exercise-induced angina attacks.

Side Effects. Beta-blocker side effects include fatigue, lethargy, vivid dreams and nightmares, depression, memory loss, and dizziness. They can lower HDL (“good”) cholesterol. Beta blockers are categorized as non-selective or selective. Non-selective beta blockers such as carvedilol and propranolol can narrow bronchial airways. These beta-blockers should not be used by patients with asthma, emphysema, or chronic bronchitis.

Patients should never abruptly stop taking these drugs. The sudden withdrawal of beta-blockers can rapidly increase heart rate and blood pressure. The doctor may advise a patient to slowly decrease the dose before stopping completely.

Calcium channel blockers reduce heart rate and slightly dilate the blood vessels of the heart, thereby decreasing oxygen demand and increasing oxygen supply. They also reduce blood pressure. CCBs vary chemically, however, and although some are helpful, others may even be dangerous for certain patients with angina.

Click the icon to see an image of the anterior heart arteries.

Long-acting nifedipine (Adalat, Procardia) and nisoldipine (Sular) and newer CCBs, such as amlodipine (Norvasc) and nicardipine (Cardene), may be beneficial for some patients with angina. They can be considered alone for patients who cannot tolerate beta-blockers, but may provide the best results when used in combination with a beta-blocker. Studies suggest that they reduce the need for repeat angioplasties. Their effects on other outcomes, including mortality rates and heart attack, are less clear.
Short-acting CCBs, including short-acting forms of verapamil, diltiazem, nifedipine, and nicardipine, are helpful for many patients with Prinzmetal's angina. However, short-acting forms of certain CCBs, such as nifedipine and nisoldipine, have been associated with severe and even dangerous side effects, including an increase in heart attacks and sudden death in some patients with unstable angina. They also increase the risk for adverse effects in patients with stable angina. Short-acting CCBs are, therefore, not used for stable or unstable angina.

There is no strong evidence that any calcium channel blockers improve survival rates. Overdose can cause dangerously low blood pressure and slow heart beats. Patients with heart failure have a higher risk for death with these drugs and should not take them. No one taking any calcium channel blocker should withdraw abruptly because such action could dangerously increase the risk of high blood pressure. Note: Grapefruit and Seville oranges boost the effects of CCBs, sometimes to toxic levels. (Regular oranges do not appear to pose any hazard.)

Angiotensin converting enzyme (ACE) inhibitors are important heart-protective drugs, particularly for people with diabetes and high blood pressure. They reduce the production of angiotensin, a chemical that causes arteries to narrow, and so are commonly used to lower blood pressure. They may also reduce risk for heart attack, stroke, complications of diabetes, and death in patients at high risk for heart disease.

ACE inhibitors include captopril (Capoten), ramipril (Altace), enalapril (Vasotec), quinapril (Accupril), benazepril (Lotensin), perindopril (Aceon), and lisinopril (Prinivil, Zestril).

Side Effects. Side effects of ACE inhibitors are uncommon but may include an irritating cough, excessive drops in blood pressure, and allergic reactions. In the past, doctors sometimes avoided giving aspirin to patients who were taking ACE inhibitors because the combination was believed to cause kidney problems. But, a 2005 study of patients with both coronary artery disease and heart failure found that taking aspirin and ACE inhibitord together is safe. The researchers also noted that taking aspirin with an ACE inhibitor can significantly reduce the risk of death for older patients with CAD and heart failure. [See In-Depth Report #14: High blood pressure.]

In 2004, the National Cholesterol Education Program issued updated recommendations on how to control cholesterol levels. These guidelines emphasize that patients should lower their LDL (“bad”) cholesterol and recommend that more people take LDL-lowering medication. Lowering LDL cholesterol and raising HDL (“good”) cholesterol can significantly reduce the risks of heart disease. Several different types of drugs (statins, bile-acid binding resins, niacin, and fibrates) are used to treat cholesterol. [See In-Depth Report #23: Cholesterol.]

Statins are the most important of these drugs. Brands include lovastatin (Mevacor), pravastatin (Pravachol), simvastatin (Zocor), fluvastatin (Lescol), atorvastatin (Lipitor), and rosuvastatin (Crestor). A major analysis of over 200 studies found that statins reduced the risk for heart problems by 60% and stroke by 17%. A 2005 review found that the more that statins lower LDL, the more they reduce CAD and other heart disease risks.

An important 2006 study found that aggressive treatment with statins may have the potential to reverse coronary artery disease. In the study, rosuvastatin reduced fatty plaque in the arteries in addition to improving LDL and HDL cholesterol levels. However, a follow-up 2007 study of rosuvastatin indicated that while the drug slowed the rate of atherosclerotic progression, it did not reverse heart disease. Future studies will continue to investigate this issue.

Side effects of statins may include stomach upset, headaches, skin rashes, muscle aches, sexual dysfunction, drowsiness, dizziness, nausea, constipation, and peripheral neuropathy (numbness or tingling in the hands and feet).

The main safety concern with statins is an uncommon condition called myopathy, which can cause muscle and joint pain and possible muscle damage. Doctors will immediately stop statin therapy if myopathy occurs. Patients should talk to their doctor about any unusual muscle discomfort or weakness, or if their urine becomes brown-colored. Statins can also affect the liver, particularly at higher doses, so patients taking these drugs should receive regular liver function tests.

Click the icon to see an image of cholesterol.

Influenza Vaccinations (Flu Shots). Evidence suggests influenza vaccinations help protect against adverse heart events (including after heart surgeries), stroke, and death from all causes in the elderly. Still, studies suggest that only two-thirds of at risk people are vaccinated, mostly because of unwarranted fears of ineffectiveness or adverse effects.

Antibiotics. Researchers have investigated antibiotics for treating patients with heart disease and past infection of the bacteria Chlamydia pneumoniae. Results from several recent large-scale clinical trials suggest that antibiotic treatment provides no benefit in preventing heart attack or other cardiac events in patients with coronary artery disease. In addition, a 2006 study indicated that short-term treatment with the antibiotic clarithromycin may increase the risk for death in patients with coronary artery disease. While it is still possible that C. pneumoniae may play a role in triggering inflammatory responses associated with ACS, antibiotic therapy is no longer considered appropriate for treatment or prevention of heart disease.

Ranolazine (Ranexa) was approved in 2006 for treatment of chronic angina. It is recommended for patients who have not responded to other angina drugs. Ranolazine is taken in combination with amlodipine, beta blockers, or nitrates. The drug appears to work better in men than in women

Gene Therapy and Angiogenesis. Proteins known as growth factors are being investigated for their ability to grow new blood vessels for supplying oxygen to the heart. After promising small trials, two large studies of genetically engineered forms of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF [GenerX]) failed to detect any benefits. Studies on therapies that actually genetically encode these proteins are underway.

Testosterone Supplements. Some trials using testosterone supplements or patches have reported improved exercise-induced blood flow in the coronary arteries and improvement in angina in some cases. Supplements of this male hormone, however, may increase the risk for prostate cancer. Experts suggest that testosterone be used only in older men with significant deficiencies in testosterone.

Selective Estrogen-Receptor Modulators (SERMs). Selective estrogen-receptor modulators (SERMs), including raloxifene (Evista), have been designed to produce the benefits of estrogen without its risks. They are thought to act like estrogen in some tissues but behave like estrogen blockers (antiestrogens) in others. Raloxifene may have some heart benefits, although it poses a risk for deep vein blood clots, which may have long-term implications for patients with heart problems. A major study is underway to determine its effects on the heart.

Surgery

Surgery is usually recommended for patients who have:

Unstable angina that does not respond promptly to medical treatment
Severe recurrent episodes of angina that last more than 20 minutes
Acute coronary syndrome
Severe coronary artery disease (severe angina, multi-artery involvement, evidence of ischemia), particularly if abnormalities are evident in the left ventricle of the heart, the main pumping chamber

Researchers have been investigating whether surgery offers any advantages if used as an early treatment for mild angina. A major analysis in 2003 reported that the use of angioplasty in patients with mild heart blockage did not reduce the risk for heart attack or death over the long term. A landmark 2007 study found that angioplasty was no better than drug therapy for preventing heart attack and stroke in patients with stable coronary artery disease. (For more information, see Angioplasty and Stents.)

Two effective surgical procedures for heart patients are:

Coronary artery bypass grafting (commonly called bypass or CABG)
Percutaneous coronary intervention (commonly called angioplasty or PCI), usually with coronary artery stent placement

Click the icon to see an image about bypass grafting.

Each of these procedures is described below.

Studies have generally reported similar survival rates with either procedure. There are some differences, however, and decision often depends on individual conditions. Patients considering surgery should discuss all options and risks with their doctor. No surgical procedure cures coronary artery disease, and patients must continue to rigorously maintain a healthy lifestyle and any necessary medications. For some patients, lifestyle changes and medications may be able to control the disease without surgery or angioplasty.

Considerations for Choosing Angioplasty with Stent Placement. Angioplasty has the following advantages for most patients. It is:

Less invasive than bypass. (Although a minimally invasive variation of bypass surgery may reduce this distinction.)
Less expensive than bypass. (Although the postoperative need for more medications and the high risk for repeat procedures to reopen the artery may reduce the long-term difference in cost between the two procedures.)
Life-saving emergency procedure for many patients with heart attacks. (The use of bypass after a heart attack has much higher mortality rates than when it is used electively and its use is controversial in heart attack patients.)

It has the following disadvantages:

The blood vessels can close up again (restenosis) so that patients require additional procedures. (New blood thinning drugs, coronary stent coatings, and radiation treatments may help to significantly reduce restenosis rates. However, there is also some indication that stents, especially drug-eluting stents, may increase the risk for blood clots.)
It is not as appropriate as bypass for many patients with angina (people with diabetes, elderly patients, or those with multi-vessel blockage). Increasingly, however, angioplasty is proving to be as safe and as effective as bypass in many high-risk patients. Patients should be sure to discuss with their doctors the relevant risks and benefits of angioplasty and bypass.

Considerations for Choosing Bypass. Bypass is usually the appropriate procedure in patients with high-risk conditions, such as:

Multi-vessel blockage. (In one report comparing surgery to angioplasty in patients with two or three blocked vessels, the mortality rate 1 year after bypass was 0.8% and after angioplasty was 2.5%. About 80% of patients in the study were men.)
Diabetes. (Bypass produces significantly higher survival rates in these patients. Some experts believe angioplasty should rarely, if ever, be used in this population.)
Being elderly.
Certain structural features, such as a left main artery narrowed by 50% or more or a very long diseased portion of the artery.

Considerations for Women. Studies have reported higher mortality rates in women than in men after any heart surgery. Some experts theorize that on average women may be older and sicker when they have a heart operation. A 2002 study, however, suggested that when women with acute coronary syndromes are given the same aggressive and early treatment as men are, their survival rates are equal or even better.

In addition to angioplasty and bypass procedures, a number of other procedures are available or under investigation for coronary artery disease. They include:

Atherectomy
Myocardial Laser Revascularization
Enhanced External Counterpulsation (EECP)

Coronary Artery Bypass Graft Surgery

Coronary artery bypass graft surgery (CABG) is a good alternative to angioplasty for many patients, but it is very invasive. The surgery involves the following processes:

Click the icon to see an animation about CABG.

The chest is opened, and the blood is rerouted through a lung-heart machine.
The heart is stopped during the procedure.
Large blood vessels supply the grafts, which are used to reroute the blood. The blood vessel grafts are transplanted in front of and beyond the blocked arteries, so the blood flows through the new vessels around the blockage.
The standard grafts now use arteries taken from the chest wall. Studies are reporting that with such grafts arteries remain open in 90% of cases after 15 years.
In general, patients with triple bypass procedures stay in the hospital for 5 days. Those with one-vessel bypass may be able to go home in 3 days.

Click the icon to see an illustrated series detailing a heart bypass surgery.

In spite of the invasive nature of this procedure, elective bypass procedures produce better long-term survival rates than angioplasty, particularly in patients with diabetes and multi-vessel blockage. Overall mortality rates after this procedure range from 1% to slightly over 2%. The risk for stroke or heart attack after a bypass operation ranges from 1.3 - 5%. Finding a surgeon who performs at least 100 of the procedures a year helps reduce the risk for complications.

Blood clots may form in the new graft, closing it up or narrowing the treated vessel over time. Therapy with aspirin and other anti-clotting drugs help keep the graft open and working properly. For long-term prevention of closure, as well as for slowing progression of atherosclerosis, aggressive treatment with cholesterol-lowering drugs may be more beneficial than standard anti-clotting drugs.

Bleeding is also a potential complication of CABG. Anti-bleeding (also called hemorrhage-sparing) drugs are sometimes used to limit blood loss in patients who undergo this surgery. In 2006, concerns were raised about one of these drugs, aprotinin (Trasylol). Data suggested that aprotinin seriously increased the risks for kidney failure, heart failure, and stroke.

An important study, published in 2007 in the Journal of the American Medical Association, compared aprotinin with two anti-fibrinolytic drugs, aminocaproic acid (Amicar) and tranexamic acid (Cyklokapron), which are also used to control blood loss. The study of nearly 4,000 patients who had CABG found that over a 5-year period, the death rate for patients who took aprotinin was 21%, and patients had a 48% increased risk of dying. By comparison, the death rate was 16% for aminocaproic acid, 15% for tranexamic acid, and 13% for no anti-bleeding drug. Because aprotinin is more expensive as well as potentially more dangerous than other anti-bleeding drugs, experts are now recommending against its use in CABG.

Minimally invasive bypass (also called buttonhole or keyhole bypass) surgeries are exciting advances in basic bypass surgery. Studies indicate good success of these procedures for patients with disease in single vessels. They are also being investigated for multiple vessels.

One variation of minimally invasive bypass uses a four-inch incision. The surgeon works on the front of the heart while it is beating slowly. To date, there have been no differences in cardiac events or later mental complications between this so-called off-pump procedure and the standard bypass procedure.
In another variation, the heart is stopped, and the patient is put on a machine that reroutes the blood through a device that keeps it oxygenated. Fiberoptic scopes and instruments are passed through a number of finger-sized incisions. The surgeon works on all sides of the heart, guided by a video image from a tiny camera inserted through a 4-inch incision.
Some advanced heart centers now use robotic systems, which allow the surgeon to perform extremely delicate maneuvers on tiny vessels through pencil-size incisions. They are not yet used for the whole bypass process.

Eventually, minimally invasive bypass procedures may prove to be less expensive, require a shorter hospital stay, and have fewer complications than conventional coronary artery bypass surgery -- or even angioplasty. At this time, however, they are experimental procedures, performed in only a few medical centers for select candidates. Long term-success rates are unknown.

Angioplasty and Stents

Percutaneous coronary intervention (PCI), also called angioplasty, involves procedures such as percutaneous transluminal coronary angioplasty (PTCA) that help open the blocked artery.

Click the icon to see an animation about percutaneous transluminal coronary angioplasty.

A typical angioplasty procedure follows these steps:

The cardiologist threads a narrow catheter (a tube) containing a catheter into the blocked vessel.
The doctor opens the blocked vessel using balloon angioplasty, in which the surgeon passes a tiny deflated balloon through the catheter to the vessel.
The balloon is inflated to compress the plaque against the walls of the artery, flattening it out so that blood can once again flow through the blood vessel freely.
In order to keep the artery open afterwards, surgeons use a device called a coronary stent, an expandable metal mesh tube that is implanted during angioplasty at the site of the blockage. (In some cases, a stent may be used as the initial opening device instead of balloon angioplasty.)
Once in place, the stent pushes against the wall of the artery to keep it open.

Click the icon to see an animation about percutaneous transluminal coronary angioplasty.

Complications occur in about 10% of patients (about 80% within the first day). Outcomes are better in hospital settings with experienced teams and backup.

Click the icon to see an illustrated series detailing coronary artery balloon angioplasty surgery.

The most important long-term complication is reclosure (restenosis), which can lead to heart attack if not treated with a repeat procedure. Stenting and other advances have helped significantly in preventing reclosure and reducing heart attack rates. Nevertheless, a repeat procedure is still needed to restore the opening in 10 - 15% of procedures that use stents.

PCI (angioplasty) has been proven to help reduce the frequency of angina attacks. It is commonly recommended for patients who have critically blocked arteries or have already had a recent, acute heart attack. PCI can also help improve survival and prevent heart attacks in patients with acute coronary syndrome (ACS). However, doctors have been uncertain about angioplasty’s benefits for survival and heart attack prevention in lower-risk patients with stable coronary artery disease.

In 2007, a landmark study was published in the New England Journal of Medicine and presented at the 2007 meeting of the American College of Cardiology. The COURAGE study found that PCI works no better than standard heart medication (drugs to control blood pressure, lower cholesterol, and prevent blood clots) in preventing heart attack, stroke, and hospitalization in patients with stable coronary artery disease. Based on this study’s findings, experts are now recommending angioplasty only for patients who have severe heart disease. For patients with stable heart disease, drug therapy may be sufficient enough treatment and allow them to safely defer having surgery.

Angioplasty is less invasive than bypass surgery, requiring only one night in the hospital. Recuperation takes about a week. Chest pain after the procedure is very common and usually due to problems other than ischemia. Mild chest pain is even more common when a stent is used, possibly because the artery is stretched.

Reclosure of the artery during or shortly after angioplasty often occurs. A number of anti-clotting drugs are used to help prevent this.

Aspirin and the anti-platelet drug clopidogrel (Plavix) are often used to prevent reclosure during the procedure.
A high dose of the anticoagulant heparin is typically given before the operation.
Intravenous glycoprotein IIb/IIIa inhibitors, powerful drugs that block platelets, also prevent reclosure after stenting in many high-risk patients, and evidence now strongly suggests that they reduce rates of heart attack and death. Eptifibatide (Integrilin) and tirofiban (Aggrastat) are the standard drugs used during angioplasty. They may be most effective if administered during angioplasty, rather than beforehand.

All of these drugs pose a risk for bleeding complications.

Narrowing or reclosing of the artery (restenosis) can occur within a year of angioplasty or even longer in 15 - 60% of angioplasty patients. Coronary stents, anti-clotting drugs, and other advances have reduced these events significantly, but have not eliminated the problem. Theories for the cause of restenosis include:

The release of oxidants (damaging unstable particles) at the surgical site may cause injury and activate immune factors that produce cellular overgrowth in smooth muscles of the blood vessels.
Other activities, including scarring, may remodel and narrow the blood vessels. (This is most likely the reason for restenosis in patients with stents.)

Symptoms of restenosis include chest pain on exertion. (Heart attacks, however, do not usually occur with such events.) The narrowing of the artery in this case is not due to blood clots, so anti-clotting drugs are not useful. Restenosis usually requires a repeat operation. A number of approaches, mostly investigative, have been developed to prevent restenosis after angioplasty.

Drug-Coated Stents. Stents coated with the drugs sirolimus (Rapamune) or paclitaxel (Taxol) have been increasingly used in the last several years. Drug-eluting stents (as they are also called) can help prevent restenosis. However, because drug-eluting stents reduce arterial tissue growth, they can increase the risks of blood clots. In late 2006, the FDA held several meetings to discuss the increased risks of blood clots associated with drug-eluting stents. The committees found that drug-eluting stents do appear to have a small increased risk of blood clots compared to bare metal stents, but not enough research has been conducted to fully determine their risks for heart attack and death.

Five studies published in the New England Journal of Medicine in March 2007 indicated that drug-eluting stents are safe and effective for patients with coronary artery disease when they are used for FDA-approved indications. Problems have arisen when these stents are used for “off-label” purposes in patients with more complicated health problems. There is still some concern as to whether all stents (both bare metal and drug eluting) are used too frequently for patients who may be better served by drugs or bypass surgery.

In February 2007, the American Heart Association and other professional organization issued an extremely important joint advisory statement. The statement advises that all patients who have drug-eluting stents must continue to take aspirin and clopidogrel (or, rarely, ticlopidine) for at least 1 year after the stent is inserted to reduce the risk of blood clots. Clopidogrel and ticlopidine are thienopyridine drugs that, like aspirin, help prevent blood platelets from clumping together. It is very important that patients who have drug-eluting stents take both aspirin and a thienopyridine drug. If for some reason patients cannot take a thienopyridine drug, they should receive a bare metal stent instead of a drug-eluting stent.

Coronary Artery Brachytherapy. Radiation treatment called coronary artery brachytherapy (Gamma One, Beta-Cath) can slow the cell growth in the arteries that causes restenosis. With this approach, any blockage in the stent is first removed, and a tube with an inflatable balloon is inserted. The surgeon then implants a temporary device that delivers radiation. Brachytherapy has shown excellent results in preventing restenosis and significantly reducing heart events and improving survival. Brachytherapy is also showing promise in preventing restenosis in stented artery grafts that were put in place after bypass surgery and later failed. However, several 2006 studies in the Journal of the American Medical Association indicated that drug-coated stents may work better than brachytherapy in preventing restenosis in failed stents. In these studies, the drug-coated stents were inserted inside the original bare metal stents.

Medications. A number of medications are being studied for prevention of restenosis, although benefits to date have been modest. Other drugs under investigation include statins, various anti-clotting drugs, and B vitamins.

Other Procedures. Other procedures under investigation to keep the arteries open use ultrasound, "soft" x-rays, and cryotherapy (very low temperatures).

Other Treatments

Transmyocardial laser revascularization (TMLR) applies laser energy directly to areas in the heart where blockage has occurred, creating 10 - 50 tiny channels. TMLR is recommended for patients with severe angina who have not responded to surgical bypass or angioplasty procedures. TMLR is not suitable for patients who have severely damaged heart muscles. A variant called percutaneous transmyocardial laser revascularization uses a small laser (a holmium YAG laser), which is smaller than the device used in TMLR and does not require open chest surgery and a general anesthetic.

Patients report improved symptoms and exercise tolerance. Both procedures carry risks for serious complications, however, including some that can be life-threatening. It is not clear if either TMLR procedure improves survival, and, in one study, the quality of life afterwards was less than with standard heart surgeries.

A noninvasive technique called enhanced external counterpulsation (EECP) has been used successfully by over a million people in China. The technique uses an air pump that inflates and deflates pressurized cuffs around the legs, causing blood to be pushed into the heart.

EECP may help patients with angina who have not had pain relief from nitrate drugs and who do not qualify as candidates for bypass or angioplasty. In different studies, it has relieved angina in over 75% of patients who used it and reduced the need for medication. The benefits persist, and there is some evidence that it produces actual cellular changes that benefit the heart. In 2002, the FDA approved EECP for the treatment of heart failure but some insurance companies still consider its use “experimental” and will not pay for it. EECP is not recommended for patients with arrhythmia, serious heart valve problems, or peripheral artery disease.

Atherectomy procedures clear the narrowed arteries by using an approach called debulking. All of these procedures use a catheter (a thin tube) that is inserted into an artery (usually in the groin) and threaded up to the blockage. Devices are inserted through the tube to remove the plaque. They include:

Rotational atherectomy, which uses a tiny cutter spinning at 2,500 rpm
Extractional atherectomy, which "shaves" the plaque
Directional atherectomy, which slices the plaques

Although they are successful in opening arteries, they offer no advantages over standard angioplasty and are used only for special cases.

Resources

www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.americanheart.org -- American Heart Association
www.acc.org -- American College of Cardiology

References

Boden WE, O'Rourke RA, Teo KK, Hartigan PM, Maron DJ, Kostuk WJ, et al. Optimalmedical therapy with or without PCI for stable coronary disease. N Engl J Med. 2007 Mar 26; [Epub ahead of print]

Crouse JR 3rd, Raichlen JS, Riley WA, Evans GW, Palmer MK, O'Leary DH, et al. Effect of rosuvastatin on progression of carotid intima-media thickness in low-risk individuals with subclinical atherosclerosis: the METEOR Trial. JAMA. 2007 Mar 28;297(12):1344-53. Epub 2007 Mar 25.

Eisenstein EL, Anstrom KJ, Kong DF, Shaw LK, Tuttle RH, Mark DB, et al. Clopidogrel use and long-term clinical outcomes after drug-eluting stent implantation. JAMA. 2007 Jan 10;297(2):159-68. Epub 2006 Dec 5.

Folsom AR, Chambless LE, Ballantyne CM, Coresh J, Heiss G, Wu KK, et al. An assessment of incremental coronary risk prediction using C-reactive protein and other novel risk markers: the atherosclerosis risk in communities study. Arch Intern Med. 2006 Jul 10;166(13):1368-73.

Garcia MJ, Lessick J, Hoffmann MH; CATSCAN Study Investigators. Accuracy of 16-row multidetector computed tomography for the assessment of coronary artery stenosis. JAMA. 2006 Jul 26;296(4):403-11.

Grines CL, Bonow RO, Casey DE Jr, Gardner TJ, Lockhart PB, Moliterno DJ, et al. Prevention of premature discontinuation of dual antiplatelet therapy in patients with coronary artery stents: a science advisory from the American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, American College of Surgeons, and American Dental Association, with representation from the American College of Physicians. Circulation. 2007 Feb 13;115(6):813-8. Epub 2007 Jan 15.

Kastrati A, Mehilli J, Pache J, Kaiser C, Valgimigli M, Kelbaek H, et al. Analysis of 14 trials comparing sirolimus-eluting stents with bare-metal stents. N Engl J Med. 2007 Mar 8;356(10):1030-9. Epub 2007 Feb 12.

Lagerqvist B, James SK, Stenestrand U, Lindback J, Nilsson T, Wallentin L; SCAAR Study Group. Long-term outcomes with drug-eluting stents versus bare-metal stents in Sweden. N Engl J Med. 2007 Mar 8;356(10):1009-19. Epub 2007 Feb 12.

Lloyd-Jones DM, Liu K, Tian L, Greenland P. Narrative review: Assessment of C-reactive protein in risk prediction for cardiovascular disease. Ann Intern Med. 2006 Jul 4;145(1):35-42.

Maisel WH. Unanswered questions--drug-eluting stents and the risk of late thrombosis. N Engl J Med. 2007 Mar 8;356(10):981-4. Epub 2007 Feb 12.

Mangano DT, Miao Y, Vuylsteke A, Tudor IC, Juneja R, Filipescu D, et al. Mortality associated with aprotinin during 5 years following coronary artery bypass graft surgery. JAMA. 2007 Feb 7;297(5):471-9.

Mangano DT, Tudor IC, Dietzel C; Multicenter Study of Perioperative Ischemia Research Group; Ischemia Research and Education Foundation. The risk associated with aprotinin in cardiac surgery. N Engl J Med. 2006 Jan 26;354(4):353-65.

Mauri L, Hsieh WH, Massaro JM, Ho KK, D'Agostino R, Cutlip DE. Stent thrombosis in randomized clinical trials of drug-eluting stents. N Engl J Med. 2007 Mar 8;356(10):1020-9. Epub 2007 Feb 12.

Mosca L, Banka CL, Benjamin EJ, Berra K, Bushnell C, Dolor RJ, et al. Evidence-based guidelines for cardiovascular disease prevention in women: 2007 update. Circulation. 2007 Mar 20;115(11):1481-501.

Nicholls SJ, Tuzcu EM, Sipahi I, Grasso AW, Schoenhagen P, Hu T, et al. Statins, high-density lipoprotein cholesterol, and regression of coronary atherosclerosis. JAMA. 2007 Feb 7;297(5):499-508.

Rosamond W, Flegal K, Friday G, Furie K, Go A, Greenlund K, et al. Heart disease and stroke statistics--2007 update: a report from the American Heart Association Statistics Committee and Stroke Statistics Subcommittee. Circulation. 2007 Feb 6;115(5):e69-171. Epub 2006 Dec 28.

Spaulding C, Daemen J, Boersma E, Cutlip DE, Serruys PW. A pooled analysis of data comparing sirolimus-eluting stents with bare-metal stents. N Engl J Med. 2007 Mar 8;356(10):989-97. Epub 2007 Feb 12.

Stewart JC, Janicki DL, Muldoon MF, Sutton-Tyrrell K, Kamarck TW. Negative emotions and 3-year progression of subclinical atherosclerosis. Arch Gen Psychiatry. 2007 Feb;64(2):225-33.

Stone GW, Moses JW, Ellis SG, Schofer J, Dawkins KD, Morice MC, et al. Safety and efficacy of sirolimus- and paclitaxel-eluting coronary stents. N Engl J Med. 2007 Mar 8;356(10):998-1008. Epub 2007 Feb 12.

Wang TJ, Gona P, Larson MG, Tofler GH, Levy D, Newton-Cheh C, et al. Multiple biomarkers for the prediction of first major cardiovascular events and death. N Engl J Med. 2006 Dec 21;355(25):2631-9.

Review Date:
4/16/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Melanoma and other skin cancers

FitSugar — Wed, 08 Oct 2008 17:35:01 -0700

In This Report

Highlights
Introduction
Melanoma
Nonmelanoma Skin Cancer
Precancerous Skin Condition...
Causes
Risk Factors
Prevention
Screening
Diagnosis
Staging
Treatment for Melanoma
Treatment for Nonmelanoma S...
Prognosis
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Risk factors

According to a report in the Archives of Dermatology, marathon runners are more likely than the general population to develop skin changes that increase the risk for melanoma.

Prevention

A study published in The Lancet indicates that the best ways to avoid sun damage are to reduce the time you spend in the sun and to wear a hat and clothing to protect as much of your skin as possible. Fabrics that are thick and tightly woven offer the best protection.

The U.S. Food and Drug Administration has approved a new type of sunscreen that may more effectively block UVA than products currently available in the United States. UVA light penetrates the skin deeper than other forms of sunlight. Exposure to UVA is believed to contribute to skin cancers. The new sunscreen, called Anthelios SX, is available over the counter.

Screening

A study published in CANCER has shown that older men are more likely to undergo a whole body skin exam if they understand their personal risk factors for melanoma and know where to go to have such an exam. The study emphasizes the importance of skin cancer awareness and education.

One-time melanoma screening for adults over age 50 seems to be as cost-effective as other nationally recommended cancer screening programs, according to a report in the Archives of Dermatology. The study authors also found that screening brothers and sisters of someone with melanoma every 2 years may also be cost-effective.

Diagnosis

Dermatologists detect melanoma earlier than other health care providers, according to an article in the Archives of Dermatology. The earlier melanoma is diagnosed and treated, the greater your chances of survival.

Introduction

Skin cancer is cancer that starts in the skin. Skin cancers are divided into two major groups:

Nonmelanoma, which includes basal cell cancer and squamous cell cancer
Melanoma, the deadliest form of skin cancer

Different skin cancers start in different layers or cells of the skin. To understand how skin cancer develops, it is useful to know something about the skin.

The Skin. The skin is the largest organ in the body and consists of layers.

The outermost layer of the skin is called the epidermis. It is only about 20 cells deep, roughly as thick as a sheet of paper.
The dermis ranges in thickness from 1 - 4 millimeters (about 1/32 - 1/8 inch). The dermis contains tiny blood and lymph vessels, which increase in number deeper in the skin.

The skin is the largest organ of the body. The skin and its derivatives (hair, nails, sweat, and oil glands) make up the integumentary system. One of the main functions of the skin is protection. It protects the body from external factors, such as bacteria, chemicals, and temperature. The skin contains secretions that can kill bacteria, and the pigment melanin provides a chemical pigment defense against ultraviolet light that can damage skin cells. The skin also helps control body temperature.

Melanocytes. A layer of cells between the epidermis and the dermis, called melanocytes, produces a brown-black skin pigment ( melanin) that determines skin and hair color. Melanin also helps protect against the damaging rays of the sun.

As a person ages, melanocytes often proliferate, forming concentrated clusters that appear on the surface as small, dark, flat, or dome-shaped spots, which are usually harmless moles or liver spots.

When cell proliferation occurs in a controlled and contained manner, the resulting lesion is benign and is commonly referred to as a mole or nevus.
Sometimes, however, pigment cells grow out of control and become a cancerous and life-threatening melanoma.

Click the icon to see an image of melanin.

Melanoma

At first, melanoma cells are found in the epidermis and top layers of the dermis. However, once they grow downward into the dermis, the cancer can come into contact with lymph and blood vessels. The thicker the melanoma, the greater the likelihood that it could spread to distant sites.

Removal of the lesion before it reaches the deeper layers of the skin is important for achieving a cure.

Superficial Spreading Melanoma. Superficial spreading melanoma is the most common and most curable. It is flat, asymmetrical, unevenly colored, and usually grows outward across the surface of the skin.

Nodular Melanoma. Nodular melanoma appears as a fast-growing brown or black lump, and its characteristics do not always fit the definitions described above. It is important to check for this type of melanoma because it is associated with an outbreak of other tumors.

Lentigo Maligna. Lentigo maligna (sometimes called Hutchinson's freckle) usually occurs in elderly people and is marked by flat, mottled, tan-to-brown freckle-like spots with irregular borders. These lesions often appear on the face or other sun-exposed areas and typically enlarge slowly for 5 - 15 years before cancer appears.

Acral Lentiginous Melanoma. Although rare, acral lentiginous melanoma is the most common melanoma among African and Asian populations. It commonly appears as a dark patch on the palms, soles, fingers, toes, under fingernails or toenails, or in mucous membranes.

Melanoma cells usually spread first through the lymph vessels or glands. Melanoma cells can also spread by way of blood vessels to various organs, spreading cancer to the liver, lungs, brain, or other sites.

Melanomas tend to grow in stages:

Most melanomas tend to be flat initially and spread laterally across the skin surface as they grow. At this early stage, which can last 1 - 5 years or longer, removal of the growth has an excellent chance of curing the melanoma. Still, there is a chance that some of these melanomas are invasive, and they should be treated aggressively.
Lesions that become raised or dome-shaped over at least part of their surface indicate that downward growth has occurred. In some cases, this growth is very rapid, occurring over a period of weeks to months.

Any suspicious lesion should be checked immediately, particularly if it has grown quickly or is partially flat and partially raised.

Common sites of melanoma in men include:

Head
Middle of the body (trunk)
Neck

Common sites of melanoma in women include:

Arms
Legs

However, any area of the skin may be affected. You may not notice melanomas if they appear on areas that are difficult to examine, such as the scalp or the back.

Less common sites for melanoma include:

Fingers
Palms
Soles of the feet
Genitals
Lips
Under the fingernails or toenails

The presence of a dark lesion under the nail that runs into the adjoining skin and doesn't heal may signal melanoma.

Rarely, melanomas appear in the mouth, in the iris of the eye, or in the retina at the back of the eye, where they may be detected during dental or eye examinations.

Click the icon to see an image of melanoma.

Nonmelanoma Skin Cancer

The two other types of skin cancers are called basal cell cancer and squamous cell cancer. These are nonmelanoma skin cancers.

Basal cell cancer starts in the lowest part of the epidermis in round cells called basal cells. Basal cell is the most common form of skin cancer. It occurs in about 800,000 - 900,000 people every year.

Basal cell cancer usually develops later in life in areas that have received the most sun exposure, such as the head, neck, back, and especially the nose. However, some basal cell cancers appear in areas not exposed to the sun.

Basal cell cancers have many different appearances:

They usually appear as a round area of thickened skin that does not change color or cause pain or itching.
Very slowly, the lesion spreads out and develops a slightly raised edge, which may be translucent and smooth. Infrequently, basal cell cancers resemble malignant melanomas in color.
Eventually, the center becomes hollowed and covered with a thin skin, which can become sore and open.
A form known as aggressive-growth basal cell cancer resembles a scar with a hard base. This type is more likely to spread and must be treated very aggressively.

Basal cell cancer is a cancerous (malignant) skin tumor involving basal skin cells. Basal cell skin cancers usually occur on areas of skin that are regularly exposed to sunlight or other ultraviolet radiation. Once a suspicious lesion is found, a biopsy is needed to prove the diagnosis of basal cell cancer. Treatment varies depending on the size, depth, and location of the cancer.

Basal cell cancers are sometimes hard to tell from benign skin conditions. For instance, occasionally they arise in unexposed skin, where they may mimic an ordinary mole, cyst, or pimple. They may be particularly difficult to distinguish from benign cysts when they occur near the eyes.

Usually, basal cells grow slowly. They are rarely deadly. Most basal cell cancers need not be treated as an emergency, although late treatment can cause disfigurement, so they should be removed as early as possible.

Basal cell cancers that are most likely to spread include those that are larger than 1 centimeter, scar-like, and those located on the cheek, nose, neck, earlobe, eyelid, or temple.

Some studies have shown that people with basal cell cancer may be at higher risk for second cancers, including melanoma, cancer of the lip, salivary glands, larynx, lung, breast, and kidney, and non-Hodgkin's lymphoma. Those at higher risk for such cancers appear to be men and anyone diagnosed before 60 with basal cell cancer.

Squamous cell cancer develops from flat, scale-like skin cells called keratinocytes, which lie under the top layer of the epidermis. Most squamous cell cancers occur on sun-exposed areas, especially the forehead, temple, ears, neck, and back of the hands. People who have spent considerable time sunbathing may develop them on their lower legs.

Types of squamous cell cancer:

Squamous cell carcinoma in situ (also called Bowen's disease) is the earliest form of this type of cancer. The cancer has not spread. Cancer areas appear as large reddish patches (often over 1 inch) that are scaly and crusted.
Invasive squamous cell carcinoma is highly likely to spread (metastasize). The skin cancer lesions can grown rapidly (over months) or slowly (over years). Eventually they become ulcerated.

Click the icon to see an image of squamous cell cancer.

Prompt treatment is desirable because squamous cell cancers are more likely to spread to local lymph nodes than basal cell cancer. Squamous cell cancers most likely to spread include:

Deep lesions, those larger than 2 cm in diameter, or patches with poorly defined margins
Recurrent lesions
Squamous cell cancer on neck, earlobe, eyelid, lips, or temple
Squamous cell cancer that develops in ulcers
Squamous cell cancer that develops on skin areas that have been previously treated with radiation or exposed to cancer-killing chemicals

People with squamous cell cancers seem to be at higher risk for other cancers, including melanoma, lung cancer, non-Hodgkin's lymphoma, bladder cancer, leukemia, testicular and prostate cancer in men, and breast cancer in women.

Precancerous Skin Conditions

Actinic (Solar) Keratosis. Actinic keratosis (also called solar keratosis) is a precancerous skin lesion caused by too much sun exposure. Such lesions can turn into cancer, but not always.

Actinic keratoses occur after years of sun exposure. They appear predominantly on sun-exposed skin, such as the face, neck, back of the hands and forearms, upper chest, and upper back. Men may develop keratoses along the rim of the ear.

Actinic keratoses have the following characteristics:

Lesions typically occur on the surface of the skin and have a sandpaper-like feel. In fact, they are sometimes more easily felt than seen.
Most lesions are pink and even flesh-colored. Some are red or brown, scaly, and tender. At times, they can resemble melanomas; even dermatologists may have trouble telling the two apart.
They can range in size from microscopic to several inches in diameter.

Keratoacanthomas. Keratoacanthomas closely resemble squamous cell cancers, but they are not malignant. The majority occur in sun-exposed skin, usually on the hands or face. They are typically skin colored or slightly red when they first develop, but their appearance typically changes:

In the early stages, keratoacanthomas are smooth, red, and dome shaped.
Within a few weeks, they can grow rapidly, usually to 1 or 2 centimeters. Some reach the size of a quarter in less than a month and can be rather disfiguring.
They eventually stop growing and become crater-like with a surrounding outer rim of tissue and sometimes have a crusty interior.

Most will spontaneously get better within 1 year, but they almost always scar after healing. Also about 25% develop into squamous cell cancers, most frequently in older people and in sun-exposed areas. Removal by surgery (sometimes by radiation) is recommended. They may also be treated with 5-fluorouracil, either as a cream or injections.

Causes

You cannot overestimate the role of the sun as the most important cause of prematurely aging skin (called photoaging ) and skin cancers.

Long-term repetitive and cumulative exposure to sunlight appears to be responsible for the vast majority of undesirable consequences of aging skin, including basal cell and squamous cell cancers.

Melanoma is more likely to be caused by intense exposure to sunlight in early life.

UVA and UVB Radiation. When sunlight penetrates the top layers of the skin, ultraviolet (UVA or UVB) radiation strikes the DNA inside the skin cells and damages it.

UVB is the main type of radiation responsible for sunburns. It primarily affects the outer skin layers. This type of ultraviolet light is most intense at midday when sunlight is brightest.
UVA penetrates more deeply and efficiently. Unlike UVB, window glass does not filter out UVA rays.

Damaging Effects of UV Radiation. Both UVA and UVB rays cause damage, including genetic injury, wrinkles, lower immunity against infection, aging skin disorders, and cancer, although the mechanisms are not yet fully clear. The following are some ways in which cancer may develop and some defensive actions that the skin uses to defend itself against DNA damage.

Oxidation and Antioxidants. The effects of UV radiation are implicated in the production of oxidants, also called free radicals. Free radicals are unstable molecules produced by normal chemical processes in the body that, in excess, can damage the body's cells and even alter the DNA. This contributes to the aging process and sometimes to cancer.
Defective DNA Repair and Protective Enzymes. Some skin cancers are caused by a breakdown in the body's mechanisms that help repair DNA damage. For example, xeroderma pigmentosum (XP) is a rare genetic disease in which the body cannot repair damage caused by ultraviolet light. Normally, a number of enzymes in the skin help protect against this damage.
Breakdown of Immune Protection. Specific immune factors protect the skin, including white blood cells called T lymphocytes and specialized skin cells called Langerhans cells. These immune system cells attack developing cancer cells at the very earliest stages. However, certain substances in the skin, particularly a chemical called urocanic acid, can suppress such immune factors when exposed to sunlight.

Defective Cell Death (Apoptosis). Apoptosis is the last defense of the immune system. It is a natural process of cell-suicide, which occurs when cells are very severely damaged. Apoptosis in the skin kills off cells harmed by UVA so that they do not turn cancerous. The peeling after sunburn is the result of these dead skin cells. However, some gene defects or other factors interfere with apoptosis. If this occurs, damaged cells can continue to spread, resulting in skin cancer.

A number of genetic factors are being investigated for their role in melanomas, including inherited genes and genetic defects that are acquired from environmental assaults (particularly sunlight).

Mutations in Genes that Regulate Cell Growth. Noninherited mutations in a number of genes that block tumor growth or other cell-protecting properties may account for cancerous changes in moles and for aggressive melanomas. The following are some examples.

Important studies have now identified a mutation in the BRAF gene that appears to be the most common event in the process that leads to melanoma. Some researchers have observed mutations in 66% of malignant melanomas. Researchers hope that agents that block this gene may be a viable treatment path.
P16 is a tumor suppressive gene that may be abnormal in some melanoma cases.
Genetic mutations that regulate Ku70 and Ku80 proteins may disrupt processes that repair strands of DNA.
Researchers are also studying mutations in a gene that encodes for a substance called epidermal growth factor (EGF). EGF plays a role in skin cell growth and wound healing, and may account for many sporadic (non-inherited) cases of melanoma.
Of further interest are mutations in genes that regulate Fas proteins, which are involved in apoptosis, a natural process of cell self-destruction. When apoptosis goes awry in melanoma cells, proliferation can become rampant.

CDKN2A Mutations. Mutations in a gene regulator called CDKN2A are the most common causes of inherited melanoma, which is still very uncommon. Mutations in this gene also appear in non-inherited cases of melanoma. Genetic tests are being developed for CDKN2A, although it is not clear if knowing the results of the test would benefit people carrying the gene.

Variations in the Melanocortin-1 Receptor Gene. One study found that the greater the number of variations from normal in a gene called the melanocortin-1 receptor gene, the greater the risk for melanoma. The gene plays an important role in determining if a person has red hair, fair skin, and sensitivity to UV radiation. Interestingly, people who had olive and darker skin and who carried one or more variations of the gene had a higher than average risk for melanoma.

Aging may weaken the body's ability to fend off impending cancers, including melanomas. As a person ages, they lose Langerhans cells that help fight off early skin cancers. The number of these immune cells decreases with age, possibly setting the stage for skin cancers in later life.

Risk Factors

In the United States, the rate of melanoma is rising more rapidly than any other cancer. According to the American Cancer Society, about 59,940 persons will be diagnosed with melanoma in 2007. More than 8,000 people will die from the cancer.

Survival rates have been improving, however, and the increase in melanomas has occurred principally with thin, less aggressive forms of the disease. Some experts believe this is due to the increased awareness from effective public programs and earlier diagnosis.

A risk factor is anything that increases your chance of getting a disease. The following factors increase your risk for skin cancer:

Age over 40
Being male
Fair skin
Too much exposure to sunlight and ultraviolet radiation
Personal history of skin cancer
Family history of skin cancer
Smoking
Certain chronic or severe skin problems
Certain medical conditions or treatments that affect your immune system
Exposure to chemicals or radiation

Melanoma in Adults. Melanoma is most common in people over 40, and the incidence increases significantly as people get older. Before age 40, melanomas are slightly more common in women than men, but after age 40 men are more often affected. Men are also more likely to have invasive and fatal melanoma than are women, although some research suggests that the higher rates are only because men fail to seek a diagnosis of suspicious skin changes before they become dangerous. The rate in women levels off somewhat between age 45 and 60; researchers speculate that menopause could have some sort of protective effect during those years.

Melanoma in Children. Melanoma is rare in children under age 10. Among children ages 10 - 14 the incidence is only 0.3 per 100,000. Between ages 14 - 19, it is still very rare, 1.3 per 100,000. Parents, then, should not be unduly alarmed by every minor skin imperfection in their children. Nevertheless, melanoma is as serious in children as in adults, and early detection is still critical.

Skin cancer is associated with both duration and intensity of sun exposure. Risk of melanoma increases with excessive sun exposure during the first 10 - 18 years of life. Sunburns are also dangerous, with five or more sunburns doubling the risk of developing cancer. Cancer typically arises many years later.

Marathon runners are more likely than the general population to develop skin changes that increase your risk for melanoma. That's because marathon runners spend a lot of time outdoors. The study findings are published in the Archives of Dermatology.

Tanning Devices. Tanning beds and sunlamps increase the risk for developing melanoma, according to a 2005 review of epidemiologic studies. Previous findings have suggested that women who use tanning devices more than once a month significantly increase their melanoma risk. Women in their 20s, as well as blondes and redheads, are especially at risk.

Ethnic Groups and Complexion. People with light skin, blue, gray, or green eyes, red or blond hair, and lots of freckles are at highest risk for developing melanoma. The risk increases for those who are easily sunburned and rarely tan, particularly if they live close to the equator where sunlight is most intense. Darker ethnic groups or those with swarthy complexions are not immune, however.

Experts have devised a classification system for skin phototypes (SPTs) based on the sensitivity to sunlight. It ranges from SPT I (lightest skin plus other factors) to IV (darkest skin). Tanning and Sunburn Risk People with skin types I and II are at highest risk for photoaging skin diseases, including cancer. It should be noted, however, that premature aging from sunlight can affect people of all skin shades.


Skin Type	Tanning and Burning Risk
I	Always burns, never tans, sensitive to sun exposure.
II	Burns easily, tans minimally.
III	Burns moderately, tans gradually to light brown.
IV	Burns minimally, always tans well to moderately brown.
V	Rarely burns, tans profusely to dark.
VI	Never burns, deeply pigmented, least sensitive.

Australia has the highest melanoma rate in the world. In the United States the rate is highest in California, Florida, and Texas. The disease is by no means limited to such sunny states and countries, however. In general, the risks are highest in regions where the population tends to be blonde and fair-skinned. Norway, for example, has had the highest rate of melanoma in Europe, and rates are soaring in the UK, particularly among men, perhaps because Britons are increasingly vacationing in sunny climates.

Melanoma. Individuals who have been diagnosed with melanoma are at increased risk for a second primary melanoma. According to one 2003 study, the risk over time for developing a second melanoma is 1% in the first year after diagnosis, 2.1% at 5 years, 3.2% at 10 years, and 5.3% at 20 years. The risk is especially higher in older men and in those with first melanomas on the upper body and face.

People with family members who have or had melanoma should also be considered at high risk and examined on a regular basis.

Nonmelanoma Skin Cancers. Nonmelanoma skin cancers, including basal and squamous cell carcinomas, increase the risk of dying from other cancers, including melanoma itself, lung cancer, non-Hodgkin's lymphoma, bladder cancer, and leukemia as well as testicular and prostate cancers (in men) and breast cancer (in women).

Psoriasis. Psoriasis increases the risk for squamous cell carcinoma, but studies conflict on whether it has any effect on melanoma. One study, in fact, reported a lower risk. Nevertheless, there is some evidence that long-term treatment for psoriasis using UVA radiation (PUVA) may increase the risk for melanoma. In one study, there was a significantly higher risk even with relatively few treatments. In one study, invasive melanoma had occurred in 2.8% of patients 15 or more years after the initial treatment.

Moles (Nevi) and Other Dark Blemishes. Certain moles and dark blemishes increase the risk for skin cancer. Any mole ( nevus) or other blemish that seems new, changing, or unusual in any way should be evaluated by a health care professional.

Some specific moles or dark blemishes that are risk factors for melanoma include:

Freckles. Freckles typically appear in children on sun-exposed areas and are usually evenly brown or tan. The more freckles a person develops as a child, the greater the risk for melanoma in adulthood.
Dysplastic (or Atypical) Nevi. About 30% of the population has moles called dysplastic nevi, or atypical moles. They are larger than ordinary moles (most are 5 mm across, about the size of a pencil eraser, or larger), have irregular borders, and are various shades or colors. Individuals who have dysplastic nevi plus a family history of melanoma (a syndrome known as FAMM) are at a high risk for developing melanoma at an early age (younger than 40). The risk for those with atypical moles and no family history of melanoma is less clear.
Large birthmarks (giant congenital nevi). Very large birthmarks more than 8 inches across are major risk factors for melanoma. In such cases, cancer usually appears by age 10. Medium-sized congenital nevi do not appear to increase the risk for melanoma. Whenever possible, very large birthmarks should be removed during infancy. Experts disagree, however, about whether small birthmarks need to be removed. Parents should watch any birthmark for changes.

The more moles one has the higher the risk that one of them will become cancerous, although the danger is still very small. A 2003 study estimated that the risk for a single mole to develop into melanoma by age 80 is 1 in 3,164 in men and 1 in 10,800 for women.

The risk is higher, however, with atypical moles. One study of people with melanoma indicated that the presence of even one atypical mole doubled the normal risk.

Some skin blemishes can look like -- but are not -- melanoma. Noncancerous moles typically have the following characteristics:

They generally remain small with clearly defined, regular borders, and uniform coloration. Some have a regular stippled or net-like pattern of pigmentation, however, and may even resemble early melanoma.
They typically first appear during childhood, puberty, or young adulthood. They may naturally grow, darken, or increase in number at certain times of life, such as adolescence or pregnancy.

Examples of moles or blemishes that may resemble skin cancer include:

Blue nevus. A benign mole that may easily be mistaken for melanoma. It is a blue-black, smooth, raised nodule and commonly occurs on the buttocks, hands, or feet.

Liver Spots. Liver spots are usually evenly brown or tan sun-induced lesions that are universal signs of aging. Occurring most noticeably on the hands and face, these harmless blemishes tend to enlarge and darken over time.

Spindle Cell (Spitz) Nevus. Children may develop a benign lesion called a spindle cell (or Spitz) nevus. The mole is firm, raised, and pink or reddish-brown. It may be smooth or scaly and usually appears on the face, particularly the cheeks. It is not harmful, but it may be difficult to differentiate from a melanoma, even for experts.

Non-Hodgkin's Lymphoma. Survivors of either non-Hodgkin's lymphoma or melanoma face a higher risk for the other malignancy. These may have common causes, such as exposure to UV radiation or shared genetic factors.

Human papillomavirus (HPV). Genital warts (human papillomavirus, or HPV) may also increase the risk of squamous cell cancer in the genital and anal areas and around fingernails.

Immunosuppression. Skin cancer risk is increased in persons whose immune systems are suppressed because of certain medications, organ transplantation, or medical conditions such as AIDS. Melanoma has also developed in patients who received heart transplants from donors who had the disease. Immune-suppressing drugs used to treat autoimmune disorders may also increase the risk of skin cancer. Potential skin cancer risks have been associated with the eczema drugs pimecrolimus (Elidel) and tacrolimus (Protopic).

Rheumatoid arthritis. Despite previous concerns, the rheumatoid arthritis drug etanercept (Enbrel) does not raise the risk for developing squamous cell skin cancer. The findings are reported in the Archives of Dermatology. Etanercept works by blocking tumor necrosis factor (TNF), an immune system chemical messenger that is involved in inflammatory processes and diseases.

Occupational exposure to radiation, such as in health care or industrial settings, may increase the risk for melanoma. Airline pilots, too, are at increased risk for melanoma. It is uncertain, however, whether this higher risk is from excessive exposure to ionizing radiation at high altitudes or because they have more opportunity to spend time in sunny regions. Experts disagree over whether frequent flyers are also at increased jeopardy.

Prevention

The best way to lower the risk your risk of skin cancer is to protect your skin from the sun and UV light.

Wear sunscreen. The use of sunscreens is complex, and everyone should understand how and when to use them. Follow instructions closely and reapply as directed after swimming or sweating. The bottom line is not that people should avoid sunscreens or sunblocks, but that they should always use them in combination with other sun-protective measures.

Many parents are now taking effective steps to protect their children, although experts worry that they are relying too much on sunscreen and less on other protective measures. Adolescents are at special risk for sun-related cancers because, according to a 2002 study, most of them do not take protective measures when out in the sun. According to the study, boys are less likely to use sunscreen than girls, but girls are more likely to get sunburn and use tanning salons more often.

The best way to prevent skin damage in any case is to avoid episodes of excessive sun exposure. The following are some specific guidelines:

Use sunscreens that block out both UVA and UVB radiation. Do not rely on sunscreen alone for sun protection. Also wear protective clothing and sunglasses.
Avoid exposure particularly during the hours of 10 a.m. to 4 p.m., when UV rays are the strongest.
Clouds and haze do not protect you from the sun and in some cases may intensify UVB rays.
Avoid reflective surfaces such as water, sand, concrete, and white-painted areas.
UV intensity depends on the angle of the sun, not heat or brightness. The dangers are greater the closer to the start of summer.
Skin burns faster at higher altitudes. One study suggested that an average complexioned person burns in 6 minutes at 11,000 feet at noon compared to 25 minutes at sea level.
Avoid sun lamps, tanning beds, and tanning salons. The machines use mostly high-output UVA rays. Some experts believe that 15 - 30 minutes at a tanning salon are as dangerous as a day spent in the sun. People should not be misled by advertising claims of "safe" tanning.

Wear protective clothing, sunglasses, and a hat to shield your face from the sun's rays. Special clothing can block out UV rays and is rated using sun protection factor (SPF) ratings or a system called the UPF (ultraviolet protection factor) index, with 50 UPF being the highest. (According to one study, this is a very reliable indicator of protection.) The clothing is expensive, however.

Everyone, including children, should wear hats with wide brims. (Even wearing a hat, however, may not be fully protective against skin cancers on the head and neck.)
People should look for loosely fitted, unbleached, tightly woven fabrics. The tighter the weave the more protective the garment.
Washing clothes over and over improves UPF by drawing fabrics together during shrinkage. An easy way to assess protection is simply to hold the garment up to a window or lamp and see how much light comes through. The less the better.
Everyone over age 1 should wear sunglasses that block all UVA and UVB rays when in the sun.

Click the icon to see a depiction of sun protection.

When choosing a sunscreen, look at the ingredients. Preparations that help block UV radiation are sometimes classified as sunscreens or sunblocks, according to the substances they contain. In general, sunscreens contain organic formulas and sunblocks inorganic formulas. However, the term sunblock is used less and less as sunscreens increasingly contain both kinds of ingredients:

Organic formulas contain UV-filtering chemicals such as octocrylene, octyl salicylate, homosalate, and octyl methoxycinnamate (block UVB), avobenzone-Parsol 1789 (blocks UVA), cinoxate, ethylhexyl p-methoxycinnamate (blocks UVB and small amounts of UVA), oxybenzone, and benzophenone-3 (blocks UVA/UVB). People should look for a wide-spectrum sunscreen that contains combinations of these ingredients and filter both UVA and UVB. Of note: para-amino benzoic acid (PABA), once a popular ingredient, is now used infrequently. PABA may actually break down in the presence of UV exposure and release harmful oxidants. And many people have an allergic reaction to it. Some products contain PABA derivatives, such as padimate O or octyl dimethyl PABA.
Inorganic formulas contain the UV-blocking pigments zinc oxide or titanium dioxide. Zinc and titanium oxides lie on top of the skin and are not absorbed. They prevent nearly all UVA and UVB rays from reaching the skin. Older sunblocks are white, pasty, and unattractive, but current products use so-called microfine oxides, either zinc (Z-Cote) or titanium. They are transparent and nearly as protective as the older types. Microfine zinc oxide may be more protective and less pasty-colored than microfine titanium oxide.

Inexpensive products work as well as expensive ones with the same ingredients. Unfortunately, there are still no standards for sunscreens, and even those claiming UVA protection may offer very little.

Organic formulas and inorganic microfine oxides do not protect against visible light, which is a problem for people who have light-sensitive skin conditions, including actinic prurigo, porphyria, and chronic actinic dermatitis.

Calculating the SPF. SPF is a ratio based on the amount of UVB radiation needed to turn sunscreen- or sunblock-treated skin red compared to non-treated skin. For instance, people who sunburn in 5 minutes and who want to stay in the sun for 150 minutes might use an SPF 30. The formula would be: 30 (the SPF number) times 5 (minutes to burn) = 150 minutes in the sun.

Protection offered by sunscreens may be classified as follows:

Minimal: SPF 2 to 11
Moderate: SPF 12 through 29
High: 30+

Although some sunscreens claim SPFs higher than 30, the added protection at such higher levels is insignificant.

SPF Levels by Age Group. Although sunscreens are safe in most toddlers and children, they should not be the first and only lines of defense. All young children should be well-covered with clothing, sunglasses, and hats. Children should be kept out of the sun during peak sunlight periods. Do not use sunscreens on babies younger than 6 months without consulting a doctor.

Older children and adults (even those with darker skin) benefit from using SPFs of 15 and over. Some experts recommend that most people should use SPF 30 on the face and 15 on the body.

Adults who burn easily instead of tanning and anyone with risk factors for skin cancer should use at least SPF 30.

Timing and Amount of Application. Apply sunscreen or sunblock liberally as follows:

Adults should include sunscreen every day, even if going outdoors for only a short time.
Apply a large amount to all exposed areas, including ears and feet. To achieve protection as indicated by the sunscreen's SPF, experts recommend half a teaspoon each for the head, neck, and each arm and a teaspoon each for the chest area, the back, and each leg.
Apply initially 30 minutes before venturing outdoors for best results. This allows time for the sunscreen to be absorbed. Then reapply every 15 - 30 minutes while being in the sunlight.
Also reapply each time after exercise or swimming. Choose a waterproof or water-resistant formula even if activities don't include swimming. Waterproof formulas last for about 40 minutes in the water, whereas water-resistant formulas last half as long.
Insect repellents reduce sunscreen SPFs by up to one-third. Use higher SPFs and very liberal application when applying both.

Possible Hazards of Sunscreens, Sun Avoidance, or Both. When used generously and appropriately, sunscreen products and sun avoidance help reduce the severity of many aging skin disorders, including squamous cell cancers. There are certain concerns, however. Sunscreens do not appear to provide protection against melanoma and some basal cell cancers. In fact, some studies have reported a higher association with sunscreen use and these skin malignancies, though not all studies report such negative results.

The reasons for this possible increased risk are unclear, though some theories include:

Until recently, many sunscreens blocked only or predominantly blocked UVB rays and not UVA, the more deeply penetrating rays now known to be especially dangerous. Studies then may not have reflected the effects of the broad-spectrum sunscreens now available, which block both UVA and UVB.
People who apply sunscreens may stay out too long during peak sunlight hours. Even if a person doesn't sunburn, UVA rays can still penetrate the skin and do harm.
People may not put on enough sunscreen. A 2002 study found that people generally apply only 20 - 60% of the recommended amount, which can provide significantly less protection than the given SPF. A later study reported that when applied at the recommended amount, a broad-screen sunscreen prevents DNA damage from UV exposure.

Underexposure to sunlight. There is some major concern that underexposure to sunlight, due to the use of sunscreens or sun-avoidance measures, may produce other health problems such as:

Vitamin D deficiency. The body makes vitamin D through a chemical reaction to UVB sunlight. Too many sun-protection measures may increase the risk for developing vitamin D deficiency. Vitamin D helps prevent rickets, osteoporosis, and some cancers, including melanoma. People who need to avoid sunlight and whose diet is low in foods that contain vitamin D should check with their doctor about taking supplements. (Warning: Vitamin D is poisonous when taken in high doses.) People with darker skin are at higher risk for deficiencies from sun protection than those with whiter skin.
Other Cancers. Although sunlight is implicated in skin cancers, it is also associated with lower risks for breast, prostate, ovarian, and colon cancers. Some protection against these cancers may be related to vitamin D production by sunlight.
Depression. Many people suffer from seasonal affective disorder (SAD), a form of depression that generally occurs in winter and is associated with exposure to less sunlight.

The bottom line is that some sunlight is important and even necessary.

A study published in 1994 in the New England Journal of Medicine found that persons with a history of nonmelanoma skin cancer who ate a low-fat diet were much less likely to develop actinic keratosis, a precancerous skin condition.

However, the low-fat diet did not appear to have any effect on the development of basal cell cancer.

Chemoprevention is the use of a substance to prevent or reduce your risk of cancer. Certain drugs have been used to help block the development of skin cancers, including melanoma. For example, a medicine called imiquimod is approved to prevent skin cancer in certain individuals. This medicine prompts the immune system to fight off foreign substances, including cancer cells. Chemopreventive agents under investigation and showing promise for skin cancer include:

Nonsteroidal anti-inflammatory drugs
Difluoromethylornithine (DFMO)
Catechins (phytochemicals found in certain foods)
Anti-aging drugs called retinoids (vitamin A derivatives)

Retinoids have been shown to prevent nonmelanoma skin cancer in patients with basal cell nevus syndrome, xeroderma pigmentosum, and transplanted organs. Oral retinoids include isotretinoin and acitretin. They may also prevent the development of squamous cell carcinoma in patients who are taking such medicines to treat psoriasis.

Early animal studies had suggested that cholesterol-lowering statins or fibrates may reduce the risk of skin cancer, but human studies have produced inconsistent results. A review of several studies has concluded that such drugs do not decrease your risk of melanoma. The findings are published in the Journal of the National Cancer Institute.

Researchers are also studying chemopreventative compounds that target genetic mechanisms in the skin. They may prove to be beneficial ingredients in creams or lotions used to prevent skin cancers on a molecular level. They include cytokine interleukin-12 and T4 endonuclease 5 (T4N5).

Studies have shown that mice with round-the-clock access to an exercise wheel developed skin cancer more slowly when exposed to UVB. Their tumors were also fewer in number and smaller. Analysis of the data suggested that exercise might trigger the death of the developing cancer cells faster than they can grow. Exercise also made the mice lose weight, and the number of tumors decreased as fat disappeared.

Antioxidants are chemicals or drugs that help prevent cell damage from unstable molecules called free radicals. Antioxidants promote to protect the skin include vitamins C and E, and coenzyme Q10 (CoQ10).

Studies suggest that vitamin E creams, particularly those made from a type of Vitamin E called alpha tocopherol, decreased skin roughness, length of facial lines, and wrinkle depth. Studies on mice have also shown that such creams reduce UV-related skin cancer.

Vitamin C is a very potent antioxidant. It is also called ascorbic acid. Most studies on the effects of antioxidants on the skin have used this vitamin. In laboratory studies, large amounts reduced skin swelling and protected immune factors from sunlight.

Selenium in the form of L-selenomethionine has protected against sun damage and even delayed skin cancer in animal studies. It is not known if such benefits apply to people.

Click the icon to read about the antioxidant selenium.

Antioxidant Skin Creams. There are wide claims about the benefits of antioxidants for wrinkles when used in skin creams. However, to date, only vitamin E, C, and selenium-based skin products have been shown to help reduce sun damage to the skin. However, most available brands contain very low concentrations of these antioxidants. In addition, the antioxidants are also not well absorbed by the skin, so the effect may be short-term.

Antioxidant Pills. One small study found that taking a combination of vitamins C and E supplements by mouth may help reduce sunburn reactions, although the protection is much less than from sunscreens. Taking the vitamins alone does not appear to have the same effect.

Other Natural Substances. The following natural substances have antioxidant properties and are being tried for sun-protection:

Both green and black tea appear to have properties that may provide some protection against skin cancers and photoaging. A 2001 study using extracts of topical green tea suggested that it might protect against ultraviolet damage. Green tea skin care products are now available, but their quality is unregulated.
Ginger also appears to have some sun protective qualities.
Silymarin, a substance found in the milk thistle family (which includes artichokes), may prevent UVB-promoted cancers in animals.
Garlic has been shown to protect animals against UVB damage. Whether these results may be applied to humans, and what quantities of garlic might be beneficial, is still unknown.

Warning Note: A wide range of herbal products may contribute to dermatological problems. Some Chinese herbal creams have been found to contain corticosteroids. Mercury or arsenic contaminants have been found in some Ayurvedic therapies. In addition, several oral herbal remedies used for medical or emotional conditions may produce irritation in reaction to sunlight (photosensitivity). They include, but are not limited to, St. John's wort, kava, and yohimbe.

Screening

Education and prevention programs have led to improved screening for skin cancer, which in turn has improved diagnosis and survival rates for melanoma. For example, a study published in CANCER has shown that older men are more likely to undergo a whole body skin exam if they were aware of personal risk factors and where they could go to have an exam performed.

Skin cancers may have many different appearances. They can be small, shiny, or waxy, scaly and rough, firm and red, crusty or bleeding, or have other features. Itching, tenderness, scaling, bleeding, crusting, or sores can signal potentially cancerous changes in any mole.

A mnemonic device, ABCDE, is used to describe several features that help to distinguish skin cancer from noncancerous growths.

Asymmetry (A). Skin cancers usually grow in an irregular, asymmetric fashion. That means one half of the abnormal skin area is different than the other half.
Border Irregularity (B). Noncancerous lesions generally have clearly defined borders. Melanoma lesions often have notched or indistinct borders that may signal ongoing growth and spread of the cancer.
Color Variation (C). One of the earliest signs of melanoma may be the appearance of various colors within the lesion. Because melanomas arise within pigment-forming cells, they are often varicolored lesions of tan, dark brown, or black, reflecting the production of melanin pigment at different depths within the skin. Occasionally, lesions are flesh colored or surrounded by redness or lighter areas of depigmentation.
- Pink or red areas may result from inflammation of blood vessels within the skin.
- Blue areas reflect pigment in the deeper layers of the skin.
- White areas can arise from dead cancerous tissue.
Diameter (D). A diameter of 6 millimeters or larger (about the size of a pencil eraser) is worrisome. Melanomas start out small; by the time a lesion has grown this large, other abnormalities will most likely be present. A doctor should examine any suspicious lesion, no matter what size it is.
Evolution (E). A lesion that is growing or changing deserves evaluation.

The ABCDE plan is a general guide. It will not help detect the early stages of nodular melanoma and may also miss amelanotic melanoma, which is not pigmented.

You should keep in mind that the most important warning sign of melanoma is a new or changing skin lesion, regardless of size or color. Changes that occur over a short period of time (particularly over a few weeks) are most worrisome.

Anyone with risk factors for skin cancer should check the entire body about once a month. People who regularly check moles on their skin may have a lower risk of developing advanced melanoma.

Experts suggest drawing a map of the body, indicating locations of moles, areas of discoloration, lumps, or other blemishes. Whenever a person conducts a self-examination, they should compare their body to the map to check for new lesions, lumps, or moles and for changes in shape, color, and size.

Some experts have defined three specific body areas to look for skin cancers, including melanomas:

Areas visible to anyone, such as the arms or face -- about 60% of melanomas are found on such areas.
Areas usually covered with clothing and visible only to the patients or their partners -- about 34% of melanomas are detected in these areas.
Hidden areas such as the scalp, buttock folds, and mouth -- about 6% of melanomas, usually more advanced, are found here.

Ask a partner to help you check these areas. Turn on a hair dryer to separate hair and examine the scalp.

Some experts recommend that everyone, especially those with a high risk of developing melanoma, have a dermatologist perform a whole body skin exam. Dermatologists detect melanoma earlier than other health care providers, according to an article in the Archives of Dermatology.

High-risk people include those with a personal or family history of melanoma and individuals with atypical nevi (irregular moles that are also larger than normal).

Such people should protect themselves from overexposure to sunlight and have a medical examination of the entire skin surface every 3 - 12 months, with the frequency depending on risk factors. Doctors may take photographs of any moles at each visit and compare them with previous photos for any changes.

Examinations for Patients Previously Treated for Melanoma. People who have had melanoma and have been treated successfully are at risk for recurrence or a second primary melanoma. Based on recurrence rates by cancer stage, a team of researchers suggested the following guidelines for being reexamined by the doctor after treatment:

Stage I patients: Yearly exam
Stage II patients: Every 6 months for years 1 and 2 and annually thereafter
Stage III patients: Every 3 months for the first year, every 4 months for year 2, and every 6 months for years 3 to 5

All patients should be checked annually after year 5. These are guidelines only and may be changed, depending on individual patient characteristics.

Some studies also suggest that regular screening of family members of people with melanoma could prevent a number of serious cases. A 2007 report in the Archives of Dermatology has called for expanded melanoma screening programs. The study found that one-time melanoma screening for adults over age 50 seems to be as cost-effective as other recommended cancer screenings. The study authors also found that screening brothers and sisters of someone with melanoma every 2 years may also be cost-effective.

Diagnosis

An experienced doctor should first rule out benign conditions that resemble melanoma, such as a noncancerous mole called a melanocytic nevi.

In rare instances, a melanoma will be difficult to detect. For example, an uncommon form, called a myxoid melanoma, may be mistaken for a benign skin disorder known as a myxoid fibrohistiocytic lesion. Other opinions from a second pathologist, computerized image processing or advanced staining techniques, may help to confirm the diagnosis.

A study published in the Archives of Internal Medicine has found that melanoma tends to be diagnosed at a later stage in persons who are not light-skinned. The study involved nearly 50,000 patients with melanoma, and included Caucasians, Hispanics, Asian/Pacific Islanders, African-Americans, and American Indians.

Some doctors now use dermoscopy (also called dermatoscopy or epiluminescence microscopy). This technique uses a handheld scope-like device that enhances the suspected lesion. It is still not clear if such devices are any better than the naked eye of a trained professional. Of interest, however, was a 2002 study suggesting that it was very useful in identifying possible melanomas in suspicious nail abnormalities and therefore avoiding many painful biopsies in this area. A 2004 study confirmed that adding dermoscopy to conventional naked-eye examination leads to fewer biopsies than using naked-eye examination alone.

A recently developed Australian device (the Solarscan) may improve detection. It is shaped like a hair dryer and takes an image of the suspicious lesion; it then reads the image and compares it with a databank of melanoma images to help determine if it is cancerous. It can also store the image of the lesion and compare it for changes with later images taken at subsequent check ups. The device is not yet used in the United States. It still requires FDA approval. Testing is under way to confirm its accuracy.

A skin biopsy is the removal of skin tissue for examination under a microscope. The exact type of biopsy depends on how deep the lesion has penetrated the skin.

Shave biopsy uses a thin surgical blade to shave off the top layers of skin. The doctor may use this type of biopsy to diagnose basal cell cancer.
Punch biopsy uses a round, cookie-cutter-like tool. It is used to take a deeper sample skin.
Incisional and excisional biopsies remove tumors that have grown deep into the skin. An incisional biopsy cuts out part of the tumor. An excisional biopsy removes the entire tumor. These biopsies are used to diagnose melanoma.

All of the above-mentioned biopsies can be done using local anesthesia.

A lymph node biopsy helps the doctor determine whether cancer has spread to one or more lymph nodes.

A procedure called sentinel lymph node (SLN) biopsy is now recommended for cancers that are thicker than 1 millimeter and generally unnecessary for those thinner than 0.75 millimeter, unless they are ulcerated. Although some evidence suggests this procedure may improve survival, no clinical trials have proven to date that this procedure improves the outlook in persons with melanoma.

Sentinel node biopsy is a technique that helps determine if a cancer has spread. When a cancer has been detected, often the next step is to find the lymph node closest to the tumor site and retrieve it for analysis. The concept of the "sentinel" node, or the first node to drain the area of the cancer, allows a more accurate staging of the cancer, and leaves unaffected nodes behind to continue the important job of draining fluids. The procedure involves the injection of a dye (sometimes mildly radioactive) to pinpoint the lymph node which is closest to the cancer site. Sentinel node biopsy is used to stage many kinds of cancer, including melanoma.

This procedure involves the following:

A tiny amount of a tracer, either a radioactively labeled substance (radioisotope) or a blue dye, is injected into the tumor site.
These substances then flow through the lymph system into the sentinel node, the first lymph node to which any cancer would spread.
The sentinel lymph node and possibly one or two others are then removed and biopsied.

The results of the biopsy can help doctors decide whether or not to remove other lymph nodes:

If the sentinel node and others shows signs of cancer then the nearby lymph nodes are removed.
If they do not, then the remainder of the lymph nodes will likely be cancer-free, and further surgery is not needed.

If melanoma has been diagnosed, the doctor will perform other tests to see if the cancer has spread, such as a chest x-ray.

Blood tests that show high levels of lactate dehydrogenase suggest that the cancer has spread. Blood tests to assess liver function and other factors to help determine specific sites where the cancer may appear.

Advanced imaging techniques, such as computed tomography (CT) or positron emission tomography (PET), may also be used. PET is particularly accurate. One study reported that PET was able to diagnose melanoma that had spread even when other tests, including CT, did not. PET can also be very accurate for identifying recurrent melanomas.

Biomarkers are specific substances that are linked to cancer. Blood tests to detect biomarkers may be used to identify microscopic cancers if sentinel node biopsy results are uncertain. Researchers are continually investigating other biomarkers that may indicate whether the cancer had spread or how severe it is, which would help determine whether treatments should be more or less aggressive.

A number of proteins and other factors detected in blood tests are showing promise as markers for microscopic metastasis. Examples include antibodies to MART-1, Melan-A, tyrosinase, and microphthalmia transcription factor (Mitf). Combinations of some of these factors may improve detection rates.

Staging

Staging is the process used to determine the size of the tumor and where and how far it has spread. When a cancer spreads, it’s said to have metastasized. Staging helps the health care team plan for appropriate treatment.

Basal cell cancer is rarely staged, because it doesn't usually spread to other organs. However, it may be staged if it's very, very large.
Squamous cell cancer may be staged in persons who have a high risk of the cancer spreading.
Melanoma is always staged.

Health professionals have come up with various methods for staging the cancer. This report uses the TNM staging system recommended by American Joint Committee on Cancer.

T = tumor. T is followed by a number to indicate thickness.
N = node. N is followed by numbers to indicate the number of lymph nodes involved.
M = metastasis. Metastasis is the spread of cancer to far away sites.

In addition a stage will include whether the melanoma is ulcerated or not, an indication of severity. Ulceration is determined if skin layers over the tumor appear indistinct under the microscope.

In general, the thicker the lesion and the farther the cancer has spread, the higher the assigned stage. The higher the stage, the worse the long-term outlook.

The earliest melanomas, which do not penetrate beneath the surface of the skin and are known as melanoma in situ, are highly curable and are called stage 0 or not given a stage.
Melanomas less than 4 mm thick suggest Stage I or II cancers, and the next step is to attempt to determine if they have spread or are likely to spread to the lymph nodes.
Melanomas that are over 4 mm thick indicated later stages. In such cases, the lymph nodes are sometimes removed to attempt to prevent the cancer from spreading, although about 70% of these melanomas have already spread.

Specific stages are as follows:

Stage I. Cure rates are excellent with surgical removal, since they are least likely to have spread.

Stage 1A. Tumor has not spread to the nodes. It is less than 1 mm and is not ulcerated.
Stage IB. Tumor has not spread to the nodes. It is less than 1 mm, but is ulcerated, or the tumor is between 1.01 and 2 mm but is not ulcerated.

Stage II. Melanomas can be cured, but the success rate lags behind that of Stage I because a small number of cancer cells may have spread to distant sites. In addition to surgery, other forms of therapy may be recommended.

Stage IIA. Tumor has not spread to the nodes. It is between 1.01 and 2 mm and is ulcerated, or it is 2.01 to 4 mm without ulceration.
Stage IIB. Tumor has not spread to the nodes. It is between 2.01 and 4 mm and is ulcerated or greater than 4 mm without ulceration.

Stage III. Survival rate is lower than earlier stages.

Stage IIIA. Tumor has spread to 1 node and it is up to 4 mm without ulceration. Sentinel biopsy has detected microscopic evidence of tumor cells in the node (micrometastasis).
Stage IIIB. Tumor is up to 4 mm without ulceration and has spread to one node or there is evidence of micrometastasis in two nodes.
Stage IIIC. Tumor is any thickness and ulceration may or may not be present. It has spread to 2 or 3 nodes. Additional "satellite" melanomas on the skin more than 2 cm (about an inch) from the original lesion may be present; these are sometimes called "metastases in transit."

Treatment for Melanoma

Treatment for melanoma depends on various factors, including:

The site of the original lesion
The stage of the cancer
The patient's age and general health

Treatment options include:

Surgery to remove the melanoma cancer cells
Chemotherapy
Immunotherapy
Radiation therapy
Palliative therapy

Surgery is the primary treatment for all stages of melanoma. Some or all of the melanoma is often removed during the diagnosis biopsy. If cancerous tissue still remains after such a biopsy, a surgeon will cut away additional tissue from the surrounding area to remove any stray cancer cells.

Mohs micrographic surgery is a technique used to remove very thin layers of skin one at a time. Each layer is examined immediately under a microscope. When the layers are shown to be cancer-free, the surgery is complete.

The amount of tissue removed depends on the size, depth, and degree of invasion:

Stage I lesions that are less than 1 mm deep require the smallest surgical cuts, usually about 1 cm off each side and downward from the original lesion.
For melanomas that are 2 mm or thicker, a margin of 3 cm is important for reducing the risk of recurrence.
Thicker lesions require wider surgical cuts.

It used to be customary to remove a large area, regardless of the stage of cancer. This potentially disfiguring approach has been abandoned because studies have shown that excising wider margins does not improve survival. Nevertheless, sometimes skin grafts may need to be taken from other body sites to help cover the wound.

Lymph Node Removal. If there is evidence that melanoma has spread to nearby lymph nodes but has not spread beyond, removing them may reduce the chance of recurrence and help patients live longer.

Surgery for Metastatic Melanoma. In some cases, surgical removal of distant tumors may be possible and prolong survival, since often in melanoma the cancer spreads first only to a single site, such as the lung or the brain.

Cryosurgery. Cryosurgery freezes skin tissue and destroys it. This procedure is not useful for most melanomas, but it might have some value in specific situations. For example, it may be effective for smaller melanomas in the eye, a location that is difficult to treat with traditional surgery. It may be useful to eliminate residual cancer cells after standard surgery for lentigo maligna melanomas, an atypical form of melanoma that has a wide surface and is difficult to treat.

Recurrence rates are very high with lentigo maligna after conservative surgery. Although this is a very slowly progressive condition, lentigo maligna can develop into melanoma. Most of these lesions appear on the face and neck, so extensive surgery can be disfiguring. Patients should discuss with their doctor carefully staged surgery to remove all diseased tissue with as little cosmetic harm as possible.

Chemotherapy is often used to treat recurrent or metastatic melanomas. This type of therapy is not intended as a cure but can prolong life and improve its quality.

Drugs Used. The following are some of the chemotherapy drugs used to treat melanoma. They may be used alone or in combination under specific situations.

Methylating agents impair the ability of cancer cells to divide. Dacarbazine (DTIC) and temozolomide (Temodar) are the ones most often used.
Nitrosoureas, which include carmustine (BCNU) and lomustine (CCNU) are often used.
Taxanes, such as docetaxel (Taxotere) and paclitaxel (Taxol), are showing some low-level activity against melanoma.

Researchers continue to investigate other chemotherapy drugs and combinations of drugs to see which works best.

Side Effects. Side effects occur with all chemotherapy drugs. They are more severe with higher doses and increase over the course of treatment.

Common side effects include the following:

Nausea and vomiting
Diarrhea
Temporary hair loss
Weight loss
Fatigue
Anemia
Depression

Serious short- and long-term complications can also occur and may vary depending on the specific agents used. They include the following:

Increased chance for infection from suppression of the immune system.
Severe drops in white blood cells (neutropenia). Certain agents, such as taxanes, pose a higher risk for this than other chemotherapeutic drugs. White blood cell count may be improved with the addition of a drug called granulocyte colony-stimulating factor (either filgrastim or lenograstim).
Liver and kidney damage.
Abnormal blood clotting (thrombocytopenia).
Allergic reaction.
Menstrual abnormalities and infertility in women. A natural hormone medication called a gonadotropin-releasing hormone analogue that puts women in a temporary pre-pubescent state during chemotherapy may preserve fertility in some women.
Rarely, secondary cancers such as leukemia.
Problems in concentration, motor function, and memory, which may be long-term.

Treating Side Effects

Drugs known as serotonin antagonists, especially ondansetron (Zofran), can relieve nausea and vomiting in nearly all patients given moderate drugs and most patients who take more powerful drugs.

Erythropoietin stimulates red blood cell production and can help reduce or prevent anemia related to chemotherapy. It is available as epoetin alfa (Epogen, Procrit) and darbepoetin alfa (Aranesp). Aranesp persists longer in the blood than epoetin alfa and so requires fewer injections.

Benefits of Chemotherapy. About 20% of cancers shrink in response to one or more of these drugs, but the effects last only 3 - 6 months. If the tumors completely disappear, the cancer may stay in remission much longer, but in virtually all cases it returns.

Chemotherapeutic regional perfusion (also called isolated limb perfusion) is a technique used to give a person very high-dose chemotherapy. It is often used effectively for metastasized or recurrent melanoma that occurs on the arm or leg. It does not appear to be useful for preventing metastasis after a first occurrence of melanoma in one of these locations.

This technique involves the following:

The blood supply to the limb with melanoma is temporarily interrupted using a tourniquet and then rechanneled through a heart-lung machine.
Anticancer drugs are added to the blood in doses up to 10 times the standard doses.
The blood is then heated to enhance the drug's potency.
The chemo-infused blood is then sent directly to the melanoma site, minimizing the likelihood of drug toxicity.
Adverse effects occur in less than 1% of cases and include severe problems in the treated limb (rarely leading to amputation) and drug leakage into the bloodstream. This can severely reduce white blood cells and lead to serious infection.

In addition to arms and legs, perfusion techniques have been tested for the pelvis, head, neck, skin of the breast, and even the abdomen.

Immunotherapy uses drugs to boost the patient's own immune system. Immunotherapy after surgery may help prevent recurrence in certain persons with melanoma.

Cytokines. Cytokines are small proteins that play an important role in the body's immune response. Certain cytokines called interferons are used as a therapy for metastatic melanoma. These medicines are usually given along with chemotherapy or other immunotherapies, or both.

A number of cytokines and combinations are being investigated. They include:

Interferon alpha-2b (Intron) is the only FDA approved immunotherapy for late stage melanoma. The most common side effects are fatigue, depression, and flu-like symptoms, which can be severe. Starting an antidepressant, such as paroxetine (Paxil), several weeks before interferon therapy may help prevent depression.
Pegylated interferon and natural human interferon are long-acting forms are under investigation. One study showed that low-dose natural interferon after chemotherapy increased the 5-year relapse-free survival rate.
Interleukin-2 (Proleukin) is a hormone-like substance that stimulates the growth of cancer-fighting white blood cells. High-dose interleukin-2 has been shown to help patients with metastatic melanoma. The drug can cause significant side effects, including very low blood pressure, heart rhythm abnormalities, severe infections, and shortness of breath. The side effects are manageable and nearly always reversible.
Granulocyte-macrophage colony stimulating factor (GM-CSF, Leukine, Sargramostim) is an injectable cytokine under study. The drug boosts production of immune cells in the blood and bone marrow. An inhaled form of the drug is being tested for melanoma that has spread to the lungs.
T-cell therapy uses white blood cells, called tumor-infiltrating lymphocytes (TIL), that taken from the patient. The cells are modified so they better fight cancer and are then reinjected back into the patient. T-cell therapy is showing promising results, especially for patients with advanced melanoma who have failed to respond to other treatments.

A chemical called histamine is a powerful inhibitor of reactive oxygen species, ROS, which may inactivate immune cells that fight cancer. Researchers are investigating to see if it can be used along with interleukin-2 cytokine therapy. In one study, the added benefits of histamine were modest except in patients with liver metastatic; in these patients, survival improved by 129 days, which was significant.

Vaccine Immunotherapy. Vaccine immunotherapy is the use of a specific vaccine to treat an existing cancer. In this case, the vaccine targets one or more proteins that are uniquely expressed by melanoma cells.

Many therapeutic melanoma vaccines are in advanced stages of development, but none is approved for use in the United States.

There are two basic types of therapeutic vaccines:

Autologous vaccines
Allogenic vaccines

Sometimes a combination of the two are used. In this case, it's called a hybrid.

Autologous vaccines are made from the patient's own cancer cells. This produces a very specific immune response that can target the patient's cancer precisely. Oncophage (HSPPC-96) and M-Vax are autologous vaccines for melanoma that have shown promise in early clinical trials. One problem with the autologous approach is that there is no way to scientifically assess outcome or even guarantee repeated success since each vaccine is unique to the individual patient. This approach is also appropriate only for select patients.

Allogenic vaccines are made in a laboratory using cells from someone other than the patient. They may be made from proteins from tumor cells, genetic material, or even bacteria. One such vaccine is Canvaxin. Early studies showed this vaccine increased survival rates in some patients with Stage 3 melanoma. However, a later trial was halted because the vaccine did not appear to improve make such patients live any longer.

Vaccine immunotherapy requires the body to build up its own defenses. It can take months before beneficial effects occur, but when they do, tumor reduction is much more lasting than with chemotherapy. Vaccines also seem to have fewer side effects than interleukin and interferon.

Antisense Compounds. Antisense compounds can prevent defective cancer genes from being translated into proteins that cause abnormal cell proliferation.

Monoclonal Antibodies (MAb). Antibodies are natural substances produced by immune cells that home in and destroy cancer cells. Scientists are identifying specific antibodies that may attack melanoma cells and cloning them to create monoclonal antibodies. MAbs have shown promise for other cancers and are now being tested for melanoma, often in combination with vaccines and other forms of immunotherapy.

In general, radiation is used to help relieve pain and discomfort caused by cancer that has spread or recurred. Radiation is not used as often for treating melanoma as it is for other forms of cancer because melanoma cells tend to be more resistant to its effects. It may be useful in some cases, however.

In some patients with tumors less than 3 cm deep, however, radiation may help slow down metastasis when combined with a super-heating process using microwaves.
Brachytherapy, in which radioactive seeds are implanted close to the tumor, has also been used with success for melanoma of the eye.
Lentigo maligna may sometimes be treated successfully with specific radiation treatments called soft, or Grenz, x-rays.
Radiotherapy using a so-called gamma knife (very focused gamma radiation) is also effective for cancer that has metastasized to the brain, in some cases halting the growth and, in rare situations, even eliminating it.

The goal of palliative therapy is to improve the patient's quality of life and relieve symptoms. It is not a cure. Advanced melanoma that has spread to distant sites often cannot be cured, although surgical removal of metastatic tumors may provide some benefit by easing pain, increasing the general quality of life, and lengthening survival.

Patients should ask their doctor's about clinical trials, studies that examine new immunotherapies (vaccines, cytokines), gene therapies, chemotherapy combinations, or other treatments.

Tetracyclines. Chemically modified tetracyclines, a common antibiotic, have been shown to modify metalloproteinase, an enzyme in the skin that promotes skin cancers, including melanoma.

Anti-Angiogenesis Agents. An anti-angiogenesis drug is one that blocks the formation of new blood vessels. The growth of new blood vessels helps cancer cells grow and spread. The anti-angiogenesis drug thalidomide (Thalomid) is approved for treatment of melanoma but requires special prescribing precautions. This drug had gained notoriety in the 1960s because of devastating birth defects in the children of women who took it during pregnancy. Scientists are investigating drugs that are chemically similar to thalidomide but have fewer side effects.

Curcumin. The yellow spice found in turmeric and curry powders may contain cancer-fighting properties. In a preliminary laboratory study, curcumin stopped the growth of melanoma cells. It is far too early, however, to recommend curcumin for clinical use.

Treatment for Nonmelanoma Skin Cancer

A number of options are available for treating nonmelanoma skin cancer, including surgery, cryosurgery, phototherapy, radiation, and topical 5-fluorouracil.

For any skin cancer and for some keratoses that require removal, surgery is the first treatment. It is usually one of the following:

Excisional Surgery. This is the surgical removal of the cancerous lesion.

Curettage and Electrodesiccation. This procedure involves scraping away of the cancerous tissue followed by electric cauterization to stop the bleeding.

Mohs Micrographic Surgery. Mohs surgery is a meticulous procedure used for skin cancers at high risk for recurrence or becoming invasive. The technique removes very thin layers of skin one at a time. Each layer is examined immediately under a microscope. When the layers are shown to be cancer-free, the surgery is complete. A human skin substitute (Apligraf) is applied to the surgical area. It helps speed up wound healing to achieve a better cosmetic effect.

Good candidates for Mohs surgery include:

Persons with squamous cell cancer
Persons with basal cell cancer greater than 1 cm (about half an inch)
Persons with basal cell cancer on the face, ear, or neck
Young people with skin cancer

Mohs surgery saves more healthy tissue than other procedures and is highly effective. It results in a 99% cure rate for primary tumors and a 95% cure rate for recurrent ones. It can be safely performed in the doctor's office. Complications are uncommon but can include bleeding and infection.

Lasers. Laser surgery may be useful for certain basal cells and for keratoses that appear on the lips, although it is not clear whether lasers offer any advantages over other surgical treatments. Lasers do not appear to be very effective for thick or tough squamous cell cancers.

Cryosurgery removes skin cancer cells or actinic keratoses by freezing the affected tissue with liquid nitrogen. Studies have shown that cyrosurgery can be used to remove even wide areas of actinic keratoses and that it may be more successful over the long term than treatment with 5-fluorouracil, the standard drug. Cryosurgery also appears to reduce the risk for squamous cell cancer in these patients.

A head-to-head comparison of a freezing technique with Mohs micrographic surgery in patients with basal cell cancer reported similar recurrence rates with each approach. Over 85% of the patients with the freezing technique were satisfied with the appearance of the area afterwards. Five-year recurrence rates were only 2.1%.

Cryotherapy achieves good cosmetic results for many patients. However, it may cause blistering and ulceration, leading to pain and infection, as well as harmless, but undesirable, skin-color changes.

In unusual cases where the skin cancer may be in an inoperable position (such as the eyelid or the tip of the nose) or if cancer has recurred multiple times, radiation therapy may be indicated. Radiation is directed at the tumor. It may take 1 - 4 weeks with treatments performed several times a week. One technique being investigated for basal and squamous cell cancer uses radiation implants (brachytherapy) and custom-made molds to specifically target the radiation to the cancer site. Studies suggest that this treatment is very effective with few complications.

Topical phototherapy with the drug aminolevulinic acid (ALA) is a nonsurgical method that is proving to be a good choice for treating actinic keratoses and nonmelanoma skin cancers. The technique involves shining blue light onto the cancer area after that patient has taken ALA. ALA accumulates in the skin cells. When the cells are exposed to intense light, the chemical causes them to die. This approach allows precise targeting of one or more lesions, leaving healthy skin unaffected.

It does not penetrate deeper than the epidermis (the top layer of the skin), so it does not produce scarring or changes in skin color, as cryotherapy or other more invasive treatments do.

It can cause pain and irritation, including stinging, itching, and burning, but in one study only 3% of patients stopped using it for these reasons. In a 2002 study, the procedure was more painful for patients with actinic keratoses than for those with nonmelanoma skin cancers. It was also painful when large areas were affected, and men experienced more pain than women.

ALA Phototherapy for Actinic Keratoses. Phototherapy works best on flat lesions performed in two treatments, and is more effective for clearing lesions on the face than those on the scalp. Phototherapy can also treat multiple lesions at the same time instead of sequentially, as in cryotherapy. Studies suggest that it may work as well as cryotherapy and achieve better cosmetic results. (More patients report burning and itching with phototherapy, however.) Phototherapy is also equal to topical 5-fluorouracil in effectiveness and achieving a satisfactory appearance.

ALA Phototherapy for Nonmelanoma Skin Cancers. In patients with squamous cell cancer-in-situ and basal cell cancer, phototherapy has been equal to cryotherapy, with superior healing and appearance afterward. A 2003 study reported that it was more effective than topical 5-fluorouracil for patients with Bowen's disease, and there were fewer side effects.

Some studies have shown that about 10% of patients using phototherapy have a recurrence within 1 year. These recurrence rates are higher than with surgery and other standard treatments. Longer-term studies are required before ALA phototherapy can be recommended for most patients with nonmelanoma skin cancers.

Chemical peeling, or exfoliation, is useful for solar keratoses on the face, especially in people with fair, dry skin. Alpha-hydroxy acids, for example, are being investigated for keratoses. Dermabrasion, which "sands" the skin, may also be effective, although scarring is possible. A 2002 study found laser resurfacing to treat severe sun damage on the face; however, it may not prevent nonmelanoma skin cancers.

A number of medications are being used for keratoses and some may be helpful for skin cancers as well. Besides cryotherapy, 5-fluorouracil is the other most commonly used treatment for actinic keratoses. Other medications are also available.


Medication	Skin Conditions Affected	Oral or Topical		Comments
5-Fluorouracil	Actinic keratoses, Bowen's disease and small nonmelanoma skin cancers.		Topical cream (Efudex, Fluoroplex) or injected gel containing 5-FU and epinephrine (AccuSite).	5-Fluorouracil (5-FU) removes actinic keratoses and is useful for some patients with a large number of lesions. It requires twice daily application for 3 - 4 weeks. It can cause significant redness, irritation, swelling, and crusting, which takes 2 - 4 weeks to heal. Newer preparations are reducing these side effects. It is still unclear if this medication protects against recurrent keratoses or future skin cancer. Of concern is the possibility that (5-FU) will clear the top of a skin cancer and obscure the rest of the cancer that lies beneath the surface of the skin. A 10-year 2003 study of patients with Bowen's disease reported that 5-FU was safe and effective, with only 2 out of 26 cancers recurring.
Diclofenac and hyaluronan (Solaraze)	Actinic keratoses (approved). Investigated for basal cell.		Topical gel applied twice a day.	Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID). When used to treat actinic keratoses, it is delivered to the skin with hyaluronan, a water-seeking molecule that helps maintain skin tension. It has modest effects and when healing occurs, it may not be evident for at least a month after treatment ends. However, it causes less irritation than 5-FU and may be useful for some people.
Imiquimod (Aldara)	FDA approved for the treatment of superficial basal cell cancer. Previously approved for treating actinic keratoses. Investigated for Bowen's disease and squamous cell cancer.		Imiquimod is a topical cream.	Imiquimod triggers the production of immune factors that help fight cell proliferation. Aldara should be used only when surgery for basal cell cancer is inappropriate. It is not approved for use on the face.
Alpha-Interferons	Basal cell cancer, squamous cell cancer.		Require injections administered three times a week.	Interferons are immune factors that are being used to treat a number of serious conditions. Alpha-interferon injections may be effective against skin cancers that are hard to treat using conventional surgical measures. Cosmetic results reported to be good or very good by 83% of patients.

Prognosis

Virtually all basal and squamous type skin cancers can be cured if treated early.

The outlook for melanoma depends on when it is diagnosed.

If melanoma is detected in its earliest form, the 5-year survival rate is 99%. Other localized forms of melanoma have very favorable outlooks.

If the cancer is found after the melanoma has spread, the 5-year survival rate drops.

If melanoma spreads to nearby areas (regional metastatic), the rate is 65%.
If melanoma has spread to distant areas of the body, the survival rate is 15%.

In general, after patients are treated for melanoma, the longer they remain free of cancer recurrence following treatment the better the chance of remaining disease-free. However, relapses are not uncommon in those whose initial melanoma was large.

Anyone who has recovered from melanoma should be especially strict about adhering to preventive guidelines and remain vigilant for suspicious lesions, since the risk for developing a new melanoma is increased even if the first one was successfully cured. Such relapses may occur years after the original diagnosis.

Resources

www.aad.org -- American Academy of Dermatology
www.cancer.org -- American Cancer Society
www.asds.net -- American Society for Dermatologic Surgery
www.mpip.org -- Melanoma Patients' Information Page
www.cancer.gov -- National Cancer Institute
www.nccn.org -- National Comprehensive Cancer Network
www.skincancer.org -- The Skin Cancer Foundation
www.epa.gov/sunwise/uvindex.html -- UV index information

References

Ambros-Rudolph CM, Hofmann-Wellenhof R, Richtig E, et al. Malignant melanoma in marathon runners. Arch Dermatol. 2006;142:1471-1474.

American Cancer Society. Cancer Facts and Figures 2007. Atlanta, GA: American Cancer Society; 2007.

Chemotherapy for Inoperable Liver Metastases from Ocular Melanoma. NCI Cancer Bulletin. November 30, 2004;1(46):7.

Dale KM, Coleman CI, Henyan NN et al. Statins and Cancer Risk: A Meta-Analysis. JAMA. 2006;295:74-80.

Delavalle RP. Melanoma chemoprevention. Program presented at: Annual meeting of the American Academy of Dermatology. March 3, 2006; San Diego, CA.

Dudley ME, Wunderlich JR, Yang JC, et al. Adoptive cell transfer therapy following non-myeloablative but lymphodepleting chemotherapy for the treatment of patients with refractory metastatic melanoma. J Clin Oncol. 2005;23(10):2346-2357.

Early Detection and Surgery for Melanoma in Lymph Nodes May Increase Survival. NCI Cancer Bulletin. May 17, 2005;2(20):2.

Freeman SR, Drake AL, Heilig LF, et al. Statins, Fibrates, and Melanoma Risk: a Systematic Review and Meta-analysis. J Natl Cancer Inst. 2006;98:1538-46.

Gallagher RP, Spinelli JJ, Lee TK. Tanning beds, sunlamps, and risk of cutaneous malignant melanoma. Cancer Epidemiol Biomarkers Prev. 2005;14(3):562-566.

Lautenschlager S, Wulf HC, Pittelkow MR. Photoprotection. The Lancet [early online publication]. May 3, 2007.

Lebwohl M. Cutaneous oncology. Program presented at: Annual meeting of the American Academy of Dermatology; March 7, 2006; San Diego, CA.

Michna L, Wagner GC, Lou YR, XE JG, Peng QY, Lin Y, Carlson K, Shih WJ, Conney AH, Lu XP. Inhibitory effects of voluntary running wheel exercise on UVB-induced skin carcinogenesis in SKH-1 mice. Carcinogenesis. May 2006.

Pennie M, Soon S, Risser J, et al. Melanoma outcomes for medicare patients. Arch Dermatol. 2007; 143:488-494.

Response to Immunotherapy for Melanoma Tied to Autoimmunity. NCI Cancer Bulletin. February 21, 2006;3(: 4.

Siwak DR, Shishodia S, Aggarwal BB, Kurzrock R. Curcumin-induced antiproliferative and proapoptotic effects in melanoma cells are associated with suppression of IkappaB kinase and nuclear factor kappaB activity and are independent of the B-Raf/mitogen-activated/extracellular signal-regulated protein kinase pathway and the Akt pathway. Cancer. 2005;104(4):879-890.

Treatment for Metastatic Ocular Melanoma. NCI Cancer Bulletin. March 7, 2006;3(10):8.

Veierod MB, Weiderpass E, Thorn M, et al. A prospective study of pigmentation, sun exposure, and risk of cutaneous malignant melanoma in women. J Natl Cancer Inst. 2003;95(20):1530-1538.

Weinstock MA. Cutaneous melanoma: public health approach to early detection. Dermatologic Therapy. 2006;19(1):26-31.

Review Date:
6/29/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Weight control and diet

FitSugar — Wed, 08 Oct 2008 17:34:58 -0700

In This Report

Highlights
Introduction
Biological and Medical Caus...
Cultural and Emotional Caus...
Risk Factors
Complications
Weight Loss and Maintenance...
Weight Management
Medications
Other Treatments
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Cancer and Weight Control:

Cancer prevention guidelines from the American Cancer Society stress the importance of maintaining a healthy weight throughout life. A healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Drug Warning:

The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

New Over-the-Counter Medication:

In February 2007, the FDA approved the first over-the-counter (OTC) weight-loss drug. Orlistat, previously available only by prescription as Xenical, will be available OTC at half its prescription strength. It will be sold under the name alli. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Research News:

A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets with varying amounts of fat and carbohydrates.
A study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9.

Effects of Obesity on the Body:

Obesity is associated with certain problems related to infertility, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.
People who are obese are at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands.
The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Introduction

A stable weight depends on a good balance between the energy you get from food and the energy you use. You use energy during the day in three ways:

As energy expended during rest (basal metabolism)
As energy used to break down food (thermogenesis)
As energy used during physical activity

Basal metabolism accounts for about two-thirds of spent energy. Your body generally uses this energy to keep your body temperature steady and keep the muscles of your heart and intestine working. Thermogenesis accounts for about 10% of spent energy.

When a person consumes more calories than the energy they use, the body stores the extra calories in fat cells. Fat cells function as energy reservoirs. They enlarge or shrink depending on how people use energy. If people do not balance energy input and output by eating right and exercising, fat can build up. This can lead to weight gain.

When energy input is equal to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person begins to accumulate fat.

Obesity is determined by measuring body fat, not just body weight. People might be over the weight limit for normal standards, but if they are very muscular with low body fat, they are not obese. Others might be normal or underweight, but still have excessive body fat. The following measurements and factors are used to determine whether or not a person is overweight to a degree that threatens their health:

Body mass index (BMI) (a measure of body fat)
Waist circumference (size around the waist)
Waist-hip ratio
Skin fold measurement (anthropometry)
The presence or absence of other disease risk factors (e.g., smoking, high blood pressure, unhealthy cholesterol levels, diabetes, relatives with heart disease)

A person's disease risk factors plus BMI may be the most important components in determining health risks with weight.

The Body Mass Index (BMI). The current standard measurement for obesity is the body mass index (BMI). In general, a BMI of 25 - 29.9 means you are overweight. Obesity is a BMI of 30 and above. Obesity is then classified into three categories:

Class 1: BMI of 30 - 34.9
Class II: BMI 35 - 39.9
Class III: BMI of 40 and greater

These guidelines are very important for people at risk for diabetes, heart disease, or certain cancers. It is also used to determine treatment approaches such as when surgery may be appropriate. The higher the BMI, the greater the risk for significant health problems.

Calculating Body Mass Index (BMI). One's body mass index (BMI) is calculated by multiplying a person's weight in pounds by 703, dividing by the height in inches, and then dividing that number by the height in inches. The steps are as follows:

Multiply one's weight in pounds by 703
Divide that answer by height in inches
Divide that answer again by height in inches

For example, a woman who weighs 150 pounds and is five feet eight inches (or 68 inches) tall has a BMI of 22.8.

Waist Circumference and Waist-Hip Ratio. The extent of abdominal fat can also be used in assessing risk of disease. Some studies suggest that:

Women whose waistlines are over 31.5 inches and men whose waists measure over 37 inches should watch their weight.
A waist size greater than 35 inches in women and 40 inches in men is associated with a higher risk for heart disease, diabetes, and impaired functioning.

Evidence strongly suggests that more body fat around the abdomen and hips (the apple-shape) is a more consistent predictor of heart problems and health risks than BMI.

The distribution of fat can be evaluated by dividing waist size by hip size. For example, a woman with a 30-inch waist and 40-inch hip circumference would have a ratio of 0.75; one with a 41-inch waist and 39-inch hips would have a ratio of 1.05. The lower the ratio the better. The risk of heart disease rises sharply for women with ratios above 0.8 and for men with ratios above 1.0.

Click the icon to see a depiction of the waist-to-hip ratio.

Anthropometry. Anthropometry is the measurement of skin fold thickness in different areas, particularly around the triceps, shoulder blades, and hips. This measurement is useful in determining how much weight is due to muscle or fat.

Biological and Medical Causes

Obesity results when a person consumes more calories than they need for the energy they use. Several different factors may influence weight gain.

About 90% of people who lose weight through dieting gain every pound back regardless of their weight-loss method.

Some evidence suggests that every person has an inherited weight. This range varies by only about 10% either up or down from some set point. For instance, a man whose "genetically-determined" weight is 200 pounds would tend to swing from 180 - 220 pounds. He would be unlikely to lose or gain more than this.

Genetic factors may play some part in 70 - 80% of obesity cases.

Appetite is determined by processes that occur both in the brain and gastrointestinal tract. Eating patterns are controlled by areas in the hypothalamus and pituitary glands (in the brain). The body produces a number of molecules that increases or decreases appetite. In some cases, the following factors may produce imbalances in this process:

Insulin. Insulin is a hormone that helps change blood sugar (glucose) into energy. During digestion, carbohydrates from our diet break down into different types of sugar molecules (including glucose). Proteins from our diet break down into smaller molecules called amino acids. Immediately after eating, blood glucose levels rise. This triggers the release of insulin, which pours into the bloodstream. Insulin pushes the glucose and amino acids into cells and muscles. Insulin and other hormones determine which nutrients will be burned for energy or stored for future use. The inability to use insulin efficiently (insulin resistance) has been associated with both obesity and diabetes.
Leptin. Leptin is a hormone that is released by fat cells. A number of scientists think this hormone may also be released by cells in the stomach. Leptin appears to play an important role in insulin resistance and fat storage in the body, but its role in obesity is unclear. The most likely scenario is that leptin levels rise as the cells store more fat. This increase in leptin levels decreases appetite. Falling levels of leptin make you feel hungry. In people who have genetically lower levels of leptin, however, the brain may be tricked into thinking that it is always starving because there is no leptin to decrease appetite. This can lead to weight gain.
Resistin. Resistin is a hormone produced by fat cells. It makes the body resistant to insulin activity. Some experts believe it may help explain the role of obesity in diabetes type 2.
Intestinal Chemicals. Ghrelin is a chemical produced in the stomach. It appears to be important in triggering the desire to eat. Peptide YY3–36 (PYY) is a substance secreted in the intestines after a meal. The level of PYY is proportionate to the number of calories a person eats. PYY tells the brain that you feel full. Deficiencies in ghrelin and PYY may contribute to some cases of obesity. Researchers are hoping that blocking ghrelin or infusing PYY may be possible treatments for obesity.
Other Chemicals. Many brain chemicals are being studied for their role in appetite stimulation and weight gain. Among them are neuropeptide Y, melanocortins, agouti-related protein, and melanocyte stimulating hormone. Pain-relieving chemicals called endorphins may be critical in reducing appetite and regulating energy use. Cholecystokinin, a hormone released in the upper intestine that stimulates digestive juices, may work to control meal size.

Insulin is a hormone produced by the pancreas that is necessary for cells to be able to use blood sugar.

Genetics may directly contribute to severe obesity in people with family histories of the problem. Genetic factors such as slow metabolisms may also make people more likely to be overweight. At least seven genetic mutations have been associated with specific and uncommon cases of severe obesity. Some are outlined below.

HOB1 (human obesity 1) is a gene that is linked to a high BMI in women.
Leptin gene variants have been linked to leptin deficiencies and obesity.
Melanocortin-4 receptor is a gene that helps turn off the urge to eat. It may not work properly in those with a family history of obesity.
Researchers have also identified a mutation in a gene for a protein called proopiomelanocortin, which results in a syndrome of obesity, red hair, and deficiencies in stress hormones.
A protein called agouti-related protein increases hunger. About 5% of severely obese people have mutations that over-respond to agouti-related protein.

Genetics also determine the number of fat cells a person has. Some people are simply born with more. It should be noted that even when genetic factors are present, a person can still control their diet.

The Thrifty Gene. Some experts think the existence of a so-called "thrifty" gene regulates changes in hormone levels, to accommodate seasonal changes. Theoretically, it works in the following manner:

In certain populations, hormones are released during seasons when food supplies have traditionally been low. This leads to insulin resistance and increased fat storage.
The process is reversed in seasons when food is readily available.
Because modern industrialization has made high carbohydrate and fatty foods available all year long, the gene no longer serves a useful function. Fat, originally stored for famine situations, is not used.

This theory could explain why the previously nomadic Native American tribes who now have Western dietary habits have such high rates of Type 2 diabetes and obesity. In the past, the traditional low-fat, high-fiber foods tribe members ate may have protected them from obesity and type 2 diabetes. Today, these tribes' diet consists of more Western foods, which are higher in fat. Furthermore, these foods are readily available year-round, and many members of the tribe are sedentary. The result is a very high incidence of Type 2 diabetes and obesity. Although genetic abnormalities may make it harder or easier to lose weight, the occurrence of obesity has dramatically increased over the past two decades, and genes cannot have changed within that short amount of time. Our ability to use the food that we eat evolved so that our body could conserve energy and store fat during times of famine. Most cases of obesity now occur in people with normal body function who live in industrialized nations, where there is more than enough food.

A number of medical conditions may contribute to being overweight, but rarely are they a primary cause of obesity.

Hypothyroidism is sometimes associated with weight gain. But, patients with an underactive thyroid generally show only a moderate weight increase of five to 10 pounds.
Very rare genetic disorders, including Froehlich's syndrome in boys, Laurence-Moon-Biedl, and the Prader-Willi syndromes, cause obesity.
Abnormalities or injury to the hypothalamus gland can cause hypothalamic obesity.
Cushing's disease is a rare condition caused by high levels of steroid hormones. It results in obesity, a moon-shaped face, and muscle wasting.
Obesity is also linked to polycystic ovarian syndrome, a hormonal disorder in women.

Click the icon to see an image of polycystic ovaries.

Some prescription medications contribute to weight gain, usually by increasing appetite. Such drugs include the following:

Corticosteroids
Female hormone treatments, including some oral birth control pills (effect is usually temporary), and certain progestins (such as Megestrol) used to treat cancer
Antidepressants and anti-psychotic drugs, including lithium and valproate
Insulin and insulin-stimulating drugs used to treat diabetes often lead to weight gain, a particularly unfortunate conflict of interest for obese individuals with type 2 diabetes

You should not stop taking any medications without your doctor's knowledge.

Cultural and Emotional Causes

Enough food is produced in the US to supply 3,800 calories every day to each man, woman, and child in the country, far more than the average person needs to sustain life. In a 2002 study, participants carefully recorded everything they ate and drank, and all activities and psychological factors surrounding the eating events. The people who gained weight ate more and their portions were larger than those who did not. This may be an obvious conclusion, but the public press often plays up biologic factors involved with obesity and overlooks the simple notion that Americans eat too much and exercise too little.

Obesity is dramatically increasing not only in American children and adults, but also in every country that has adopted similar cultural habits. The World Health Organization now considers obesity to be a global epidemic and a public health problem as more nations become "Westernized." In spite of the proven health risks of obesity, the government, insurance companies, and the medical profession do not spend nearly enough money to balance the commercial and cultural pressures that are producing millions of overweight people.

In 2007, the Robert Wood Johnson Foundation sounded a positive note with the announcement of a $500 million initiative, aimed at “reversing the childhood obesity epidemic by 2015.” The money will be used for research, education, and activities that promote healthy eating among America’s children.

Perhaps the primary reason for the dramatic rise in obesity is the sedentary (inactive) lives led by most Americans, including children and young people. In a 2003 study comparing modern life to the past, researchers found that labor saving devices had reduced a person's energy use by 111 calories a day -- adding up to an extra 11 pounds a year. Half the difference in energy use was due to less walking. At the same time, according to the U.S. Centers for Disease Control and Prevention, between 1970 and 2000 the typical American man increased his caloric intake by 168 calories a day (good for 17 pounds a year) while the average woman added 335 calories a day.

Regular television watching has been singled as the most hazardous pastime. According to a major 2003 study, for every 2 hours a person spends in front of the TV each day, the risk for obesity increases by 23% and for type 2 diabetes by 14%. In the study, TV watching produced the lowest metabolic rates compared to sewing, playing board games, reading, writing, and driving a car. Just the act of watching TV encourages unhealthy snacks and eating patterns. In addition, the advertising on the television complicates the problem by promoting fast foods, cereal, and snack products that are high in salt, fats, and carbohydrates. Even worse, much of these advertisements are directed at children -- the most vulnerable group.

People are not only eating more food than they did 20 years ago, they are also replacing home cooking with packaged foods, fast food, and dining out. This behavior, according to studies, places people at higher risk for obesity. Fast foods may be more harmful than restaurant cooking. These foods tend to be served in larger portions. They generally contain more calories and unhealthy fats, and less nutritious ingredients, than homemade or restaurant meals. Snack foods and sweet beverages, including juice and soft drinks, are specific problems that add to the increasing rates of obesity. Frequent small, healthy meals (instead of two or three large daily meals) have been associated with lower weights.

People react differently to stress. Some overeat and gain weight and others stop eating and lose weight. People who gain weight in response to stress often overeat foods high in sugar, fats, and salt. A 2003 study on rats suggested that stress hormones increase the pleasure of eating such so-called "comfort foods." Furthermore, the study supported previous research showing that stress-related eating was connected to the unhealthy accumulation of abdominal fat.

Risk Factors

Where you live plays a role in your risk for obesity. Simply living in the United States makes a person more susceptible to obesity. The prevalence of obesity in America has risen dramatically over the past few years and continues to increase.

According to the latest figures available, 32.2% of American adults (aged 20 and older) are obese (BMI over 30) -- up from about 23% in the early 1990s.
The number of Americans aged 20 - 74 who were overweight also increased -- from about 44.8% in 1960 to 65.2% in 2002.
The rate of extreme obesity (BMI > 40) increased from 0.8% in 1960 to 4.9% in 2002.
Obesity has increased in every state, in both men and women, across all age groups, and in every ethnic group, although some groups may face slightly higher risks than others.

Fat tends to settle in certain regions, depending on gender. Women gain fat predominantly in the stomach, hips and thighs, while men tend to gain fat in the belly and waist.

Risk by Age. People of any age are at risk for obesity. More children and adolescents are overweight in America than ever before. Gaining some weight is inevitable with age and adding about 10 pounds to a normal base weight over time is not harmful. The current weight gain in American adults over 50, however, is significant. By age 55, the average American has added nearly 40 pounds of fat during the course of adulthood. This condition is made worse by the fact that muscle and bone mass decrease with age.

Risk by Gender. In men, BMI tends to increase until age 50 and then it levels off. In women, weight tends to increase until age 70 before it plateaus. A 2000 study found that there are three high-risk periods for weight gain in women.

The first is at the onset of menstruation, particularly if it is early. In fact, a study released in March 2007 found that obesity in young girls results in early puberty -- as early as age 9. This, in turn, increases the risk for more weight gain as girls enter puberty.
The second is after pregnancy, with higher risk for women who are already overweight.
Finally, many women gain weight after menopause.

These findings are significant because they may allow women to target high-risk times, and consequently prevent unnecessary weight gain.

Risk by Economic Group. Obesity is more prevalent in lower economic groups. One 2002 study reported that women who reported that they did not have enough food were more likely to be overweight than those who said they had sufficient food. Researchers discovered that the low-income women tended to have fewer fruits and vegetables but were actually taking in more calories a day than higher-income women. However, obesity is increasing in young adults with college education as well as in other groups.

Ethnic Groups. Among ethnic groups in general, African-American women are more overweight than Caucasian women but African-American men are less obese than Caucasian men. (Currently, 80% of African-American women are overweight.) Hispanic men and women tend to weigh more than Caucasians.

US Regions. Regionally, the prevalence of obesity is lowest in the Western states and highest in the South.

A number of dietary habits put people at risk for becoming overweight:

Night-Eating Syndrome. Night-eating syndrome is defined as having no appetite in the morning, insomnia, and consuming more than half of daily food intake after 6:00 PM. It is associated with obesity and is difficult to treat. Stress reduction and relaxation techniques may be helpful.
Binge Eating and Eating Disorders. About 30% of people who are obese are binge eaters who typically consume 5,000 - 15,000 calories in one sitting. To be diagnosed as a binge eater, a person has to binge at least twice a week for 6 months. Many experts believe that binge-eating carbohydrates causes an increase in a natural opiate leading to dependence on carbohydrates. Therefore, this condition should be treated as an addiction. Other eating disorders are bulimia and anorexia. Bulimia is binge eating followed by purging in order to lose weight. Anorexia nervosa is a mental illness in which the person refuses to maintain weight at the normal level. The patient with anorexia has a terrible fear of getting fat, and an abnormal perception of what his or her body looks like. Both conditions pose risks for serious medical problems, and anorexia nervosa can be life-threatening. A combined approach using behavioral therapy and antidepressants may help these individuals. [See In-Depth Report #49: Eating disorders.]
Restrained Eating. Some people, mostly middle-aged women who have normal weight, have a pattern referred to as restrained eating. This pattern requires a high level of conscious control and usually maintains a lower weight. However, such restraint places these individuals at higher risk for loss of control and subsequent overeating.
Infrequent Eating. There is some evidence to suggest that eating small frequent meals uses more calories than infrequent large meals. It should be strongly noted, however, that packaged snack foods add calories and some do not produce a feeling of being full, so that people simply eat more than they should.

Anyone with Sedentary Lifestyles. Office workers, drivers, and anyone whose lifestyle involves sitting for long periods are at higher risk for obesity.

Ex-Smokers. The trend toward weight increase has followed the trend for quitting smoking. Nicotine increases the metabolic rate, and quitting, even without eating more, can cause weight gain, which may be considerable. It is important to note that weight control is not a valid reason to smoke. People in previous centuries did not smoke cigarettes, nor were they usually obese.

Shift-Workers. A recent study found that individuals who work late shifts (between 4 p.m. and 8 a.m.) tend to eat more and take longer naps than day workers and are more likely to gain excess weight.

People with Disabilities. Obesity rates are higher than average in people with physical or mental disabilities. Those with disabilities in the lower part of the body, such as the legs, are at highest risk.

Overweight in children and adolescents is rising at an alarming rate. In 2004, 19% of young children aged 6 - 11 were overweight, an increase of 8% from 1994. Among children aged 25, 13.9% were overweight in 2004, up from 7.2% 10 years earlier.

Definition of Overweight in Children

Children and adolescents are considered to be overweight if their BMI is above 95% of the children in their age and sex categories. Ethnic variations, timing of growth spurts, and higher normal fat levels around puberty can affect these measurements.

Causes and Risk Factors for Overweight in Children

Lifestyle Factors. Without educational or parental guidance, children are extremely vulnerable to the intense cultural pressures that are largely responsible for the obesity epidemic. The following are some specific problems created by the culture:

Excessive television watching plays a critical role in obesity in children. Not only is it a sedentary activity, but television also offers innumerable temptations with its advertisements for fast foods, sugar cereals, and unhealthy snacks. In one study obesity rates were lowest in children who watched television 1 hour or less a day and highest in those who watched 4 or more hours.
Sugar, particularly from soda, other sweetened beverages, and fruit juice, may be the major contributor to childhood obesity. One study reported that drinking soda regularly increases a child's risk for obesity by 60%. The average American adolescent consumes 15 - 20 extra teaspoons of sugar a day just from soda and sugary drinks. (Juice, while better than soda, is still filled with sugar.)
Less physical exercise and greater sedentary activities play another significant role in obesity in children. A high level of physical activity -- not just using up energy -- is important for weight control in young people. Unfortunately, according to one study, the annual distance walked by children has fallen by nearly 30% since 1972, partially because more parents are driving their children to school out of fear of abduction, molestation, and traffic accidents. Schools are also offering fewer opportunities for daily physical activities than in the past.

Neither the media nor the educational system has strong well-financed programs that encourage healthy alternatives, including exercise and healthy foods.

Family History. Parental obesity more than doubles the risk that a young child, whether thin or overweight, will become obese as an adult. In older children and teenagers, obesity in parents starts to count less as a predictor for body weight than their own weight. The risk for obesity may be due to environmental or genetic factors, or both.

Ethnic and Socioeconomic Factors. As in adult populations, children from lower socioeconomic groups and minority populations are at higher risk for obesity. For example, among young Mexican Americans and African-Americans, there has been an increase in overweight prevalence of about 13% to over 23%.

Factors Surrounding Birth. The following factors surrounding birth are associated with a child's weight:

Low birth weight is a risk factor for later obesity and diabetes. One theory is that humans have a "thrifty gene" that produces metabolic changes in infants with low birth weight. Such changes affect insulin and fat accumulation, in order to produce a "catch-up" weight in these young children as quickly as possible. This rapid weight gain in infancy increases the risk for obesity in children and young adults.
In a study of African-American children, having an overweight pregnant mother increased the risk for later weight gain, but low birth weight did not.

Although some small studies have reported protection against obesity from breastfeeding, evidence is weak. In a 2003 study, for example, children who were breast fed for 3 - 5 months had a lower risk for obesity, but prolonged breastfeeding had no effect. Nevertheless, given the healthful effects of breast feeding and the possibility that it may have even a slight impact on childhood obesity, it is highly recommended.

Biological Effect of Childhood Overweight on Adult Weight

Achieving a healthy weight becomes more difficult as children get older. The odds of obesity persisting into adulthood ranges from 20% in 4 year olds to 80% in teenagers. One reason for the persistence is biological. The fat cells change in number or mass depending on a person's age:

Fat cells themselves multiply during two growth periods: early childhood and adolescence. Overeating during those times increases the number of fat cells. Some people are also just born with more fat cells.
After adolescence, fat cells tend to increase in mass rather than quantity, so that adults who overeat and gain weight tend to have larger fat cells, not more of them. This growth in mass may be responsible for the greater risk of persistent obesity among teenagers compared to small children who are overweight. Losing weight after adolescence reduces the size of the fat cells but not their number, so weight loss becomes much more difficult.

Health Consequences of Childhood Overweight

Children and adolescents who are overweight have poorer health than other children. Studies are reporting unhealthy cholesterol levels and high blood pressure in overweight children and adolescents. Of great concern is the dramatic increase in type 2 diabetes in young people, which is largely due to the increase in overweight children. Overweight in children is also linked to asthma, gallbladder problems, sleep apnea, and liver abnormalities. Overweight girls are more likely to enter puberty early, according to a new study, and subsequently be at higher risk for breast cancer.

It is not clear yet how many of these childhood problems persist in people who achieve normal weight as adults. Staying overweight into adulthood certainly carries health risks.

Managing Overweight Children

Childhood obesity is best treated by a non-drug, multidisciplinary approach including diet, behavior modification, and exercise. Evidence suggests that reducing calories by only 200 - 260 per day would prevent weight gain in most overweight children. Here some tips for children who are overweight:

Limit (or avoid, if possible) take out, fast foods, high-sugar snacks, commercial packaged snacks, soda, and sugar-sweetened beverages (including too much juice).
Let children snack but make sure the snacks are healthy. Eating small frequent healthy meals (instead of two or three large ones) has been associated with being thinner and having a better cholesterol profile.
Let children choose their own food portions. One study indicated that children naturally ate 25% less when they chose their own portion size. When they were given larger portions their bite sizes were larger and they ate more.
Do not criticize a child for being overweight. It does not help and such attitudes could put children at risk for eating disorders, which are equal or even greater dangers to their health.
Limit television, video games, and computer use to a few hours a week. This can contribute significantly to weight control, regardless of diet and physical activity.
For young children, try the traffic-light diet. Food is designated with stoplight colors depending on their high caloric content: Green for go (low calories); yellow for "eat with caution" (medium calories); red for "stop" (high calories).
Try a low glycemic index diet. This may be as beneficial, and possibly more, than a standard reduced-fat diet in overweight children. Such a diet focuses on certain carbohydrates (for example, dried beans and soy), which raise blood sugar more slowly than other types of carbohydrates. This diet is sometimes used in diabetes, and as a dietary approach in overweight adults. [See In-Depth Report #42: Diabetes diet.]

Click the icon to see an image about TV watching.

Click the icon to see an image of childhood overweight.

Complications

General Adverse Effects of Obesity. Obesity, defined as a BMI of 30 or over, accounts for nearly 300,000 deaths in the U.S. each year. It is associated with more chronic health problems than smoking, heavy drinking, or poverty. Furthermore, given the current increase in obesity, it will surpass smoking as the most important preventable cause of death in America.

Some studies indicate the following health risks by body mass:

The lowest risks for heart disease, diabetes, and some cancers are in people with BMI values of 21 - 25.
The risks increase slightly when BMI values are between 25 - 27.
The risks are significant in BMIs between 27 - 30.
The same risks are dramatic at BMIs over 30.

Anyone with chronic health problems such as heart or lung disease, stroke, or arthritis, should be concerned about extra weight. This same concern also applies to people with known risk factors for such conditions.

Metabolic Changes. As fat stores increase, the fat cells themselves enlarge and produce chemicals that increase the risk for several diseases. Such diseases may include diabetes, high blood pressure, gallbladder disease, and some cancers.
Increased Mass. The increased body weight itself causes problems that result in injury and diseases, including osteoarthritis and sleep apnea.
Harmful Fat Cell Types. Weight concentrated around the abdomen and in the upper part of the body (the apple shape) poses a higher health risk than fat that settles around the hips and flank (the pear shape). Fat cells in the upper part of the body appear to have different qualities from those found in the lower parts. In fact, studies suggest a higher risk for diabetes in people with the "apple shape" and lower risk in those who are "pear shaped."

Weight gain in the area of and above the waist (apple type) is more dangerous than weight gained around the hips and flank area (pear type). Fat cells in the upper body have different qualities than those found in hips and thighs.

General Adverse Effects of Being Overweight (Not Obese). It is still not clear if being overweight (a BMI of 25 - 29.9) hurts healthy people with no risk factors for serious illnesses.

According to one 2001 study, just being overweight increased the risk for developing diabetes, gallstones, hypertension, heart disease, stroke, and colon cancer. The risk rose according to how much the individuals were overweight. In any case, adults who are overweight in middle age face a poor quality of life as they age, with the quality declining the greater the weight. One study suggested, however, that being over 65 and overweight (but not obese) is not associated with higher mortality rates.

Some experts argue, in fact, that in anyone who is not severely obese, it is the unhealthy diet and sedentary lifestyle that causes harm -- not weight per se. In support of this argument, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Being somewhat overweight may also have some benefits under specific circumstances:

In older women, some excess fat may produce extra estrogen that helps slow down bone loss, and insulates bones from fall-related injuries. It should be strongly noted, however, that when older overweight women lose weight they report less pain, improved vitality, and improved physical function. The same positive effect of overweight does not appear to hold in older men.
Conditioned athletes may have high BMIs because of very dense muscle tissue. Being fit in general may protect many overweight people.
Some evidence suggests that Caucasians have the lowest mortality with BMIs of 24.3 - 24.7 while African-Americans are better off in the range of 26.8 - 27.1.
Children may have higher normal fat levels during growth spurts and around puberty.

Individuals with a BMI of at least 30 have a 10 - 50% increased rate of death from all causes, compared with individuals with a BMI of 20 - 25. Mortality rates from many causes are higher in obese people, but heart disease is the primary cause of death. People who are obese have almost three times the risk for heart disease as people with normal weights. Being physically unfit adds to the risk.

Weight concentrated around the abdomen and in the upper part of the body (apple shape) is particularly associated with insulin resistance and diabetes, heart disease, high blood pressure, stroke, and unhealthy cholesterol levels. Fat that settles in a pear shape around the hips and lower body appears to have a lower association with these conditions.

Obesity poses many dangers to the heart and circulatory system.

Damage in the Blood Vessels. As people age, changes in body fat (particularly increasing abdominal fat) seem to cause stiffness in the aorta, the major blood vessel leading from the heart. Studies are finding higher levels of a factor called C-reactive protein (CRP) in people with obesity and abdominal fat. CRP is now considered to be a marker for inflammation and damage in the arteries. (Losing weight reduces CRP levels.)

High Blood Pressure. High blood pressure is the health problem most commonly associated with obesity, and the greater the weight, the greater the risk. High blood pressure carries serious risks of stroke, heart attack, and heart failure. The link between obesity and high blood pressure is complex, and may be a combination of genetic, population, and biological factors. Many studies have reported that modest weight loss is beneficial for reducing existing high blood pressure. [See In-Depth Report #14: High blood pressure.]

Heart Failure. An important 2002 study reported that obesity might account for 11% of heart failure cases in men and 14% in women. This link existed independently of other risk factors, such as high blood pressure, sleep apnea, and diabetes, which are also associated with obesity. The biologic mechanisms involved in obesity that lead specifically to heart failure are not clear. [See In-Depth Report #13: Heart failure.]

Unhealthy Cholesterol Levels and Lipid Levels. The effect of obesity on cholesterol levels is complex. Although obesity does not appear to be strongly associated with overall cholesterol levels, among obese individuals triglyceride levels (the major form of fat storage in the body) are usually high, while HDL levels (the "good" cholesterol) tend to be low. Both conditions are risk factors for heart disease. [See In-Depth Report #23: Cholesterol.]

Click the icon to see an image of coronary artery disease.

Stroke. Obesity is also associated with a higher risk for stroke. [See In-Depth Report #45: Stroke.]

Type 2 Diabetes and Insulin Resistance. Most people with type 2 diabetes are obese and, in fact, studies strongly suggest that weight loss may be the key in controlling the current epidemic of type 2 diabetes. The common factor appears to be insulin resistance. Insulin is a critical hormone in the use of sugar. In type 2 diabetes, different factors cause the body to become insulin resistant -- that is, the body can no longer respond properly to insulin. This has the effect of increasing sugar levels in the blood, the hallmark of diabetes. Both obesity and insulin resistance, at different phases, are marked by high levels of certain chemicals. It is not known yet if the higher levels are simply a product of obesity, or play some role in causing diabetes.

Insulin resistance is also associated with high blood pressure and abnormalities in blood clotting. Some research indicates that obesity, in fact, is the one common element linking insulin resistance, diabetes type 2, and high blood pressure. [See In-Depth Report #60: Diabetes - type 2.]

Metabolic Syndrome. Metabolic syndrome (also called syndrome X) is a pre-diabetic condition that is significantly associated with heart disease and higher mortality rates from all causes. The syndrome consists of obesity marked by abdominal fat, unhealthy cholesterol levels, high blood pressure, and insulin resistance. A 2002 study estimated that nearly a quarter of the U.S. population now has this condition. Even worse, according to a 2003 study, nearly a million American teenagers have this syndrome. A combination of weight loss and exercise is an effective treatment for this syndrome.

The American Cancer Society released new cancer prevention guidelines in September 2006. The guidelines stress the importance of keeping a healthy weight throughout life. The Society indicates that healthy weight is even more important than eating specific healthy foods, when it comes to cancer prevention.

Obesity has been associated with a higher risk for cancer in general and specific cancers in particular. Studies have also suggested that restricting calories reduces the risk for cancer. Some experts believe that effective weight control for children and adults could reduce cancer rates by 30 - 40%. One way obesity may increase the risk for cancer is its association with high levels of hormones called growth factors, which can trigger rapid cell production leading to cancer.

Uterine Cancers. The risk of uterine cancer in obese women appears to be two or three times higher than in thinner women.

Prostate Cancer. New studies from 2005 and 2006 report that obesity is associated with an increase in prostate cancer mortality, although not with the risk for less aggressive forms of prostate cancer.

Click the icon to see an image of prostate cancer.

Breast Cancer. Studies are mixed on the association between obesity and breast cancer. A number of studies have linked obesity to breast cancer in postmenopausal women, particularly in women who begin to gain weight after age 18.

Click the icon to see an illustrated series detailing a breast cancer surgery (mastectomy).

Gallbladder Cancer. Obese women are at higher risk for gallbladder cancer.

Gastrointestinal Cancers. A number of cancers in the gastrointestinal tract have been associated with obesity:

Cancer of the esophagus may be due to a higher incidence of gastroesophageal reflux disorder (heartburn) in people who are overweight.
Colon cancer has been linked to increased body mass in both men and women.
Pancreatic cancer and obesity have been weakly linked, with one study reporting a lower risk in overweight people who are physically active.

Click the icon to see an illustrated series detailing a colon cancer surgery.

Muscles and Bones

Obesity places stress on bones and muscles. Studies report that the incidence of osteoarthritis is significantly increased in people who are overweight. People who are obese are also at higher risk for carpal tunnel syndrome and other problems involving nerves in their wrists and hands. It should be noted that some weight may be protective against osteoporosis (loss of bone thickness).

Obesity increases the risk for the following mouth and eye disorders:

Gum disease
Cataracts
Maculopathy, an eye disease related to aging

Infertility. Abnormal amounts of body fat, either 10 - 15% too high or too low, can contribute to infertility in women. Obesity is specially related to certain infertility problems, such as uterine fibroids or menstrual irregularities. In men, obesity can contribute to reduced testosterone levels.

Effect on Pregnancy. Obesity has many dangerous effects on pregnancy. These include high blood pressure, gestational diabetes (diabetes, usually temporary, that occurs during pregnancy), urinary tract infections, blood clots, prolonged labor, and higher fetal death rate in late stages of pregnancy. Obesity is also associated with increased rates of cesarean delivery. Infants of women who are obese are also at higher risk for neural tube birth defects, which affect the brain or spine. Folic acid supplements, ordinarily effective in preventing these conditions, may not be as protective in overweight women.

Obesity is thought to be a risk factor for symptoms of adult-onset asthma. Though there is evidence that obesity causes wheezing and shortness of breath, it does not appear to be strongly associated with the disease mechanisms in the lungs that cause true asthma.

Obesity also puts people at risk for hypoxia, a condition in which there is not enough oxygen to meet the body's needs. Obese people need to work harder to breathe. They tend to have breathing muscles and lungs that do not work as well as those in thinner people.

The Pickwickian syndrome, named for an overweight character in a Dickens novel, occurs in severe obesity when lack of oxygen produces intense and chronic sleepiness and, eventually, heart failure.

Nonalcoholic Fatty Liver Disease. People with obesity, particularly if they also have type 2 diabetes, are at higher risk for a condition called nonalcoholic fatty liver disease, also called nonalcoholic steatohepatitis (NASH). This condition causes liver damage that is similar to liver injury seen in alcoholism. In some cases, it can be very serious and require liver transplantation. It occurs in about half of people with diabetes, and 20 - 50% of obese people, depending on how severe their obesity is. NASH can also occur in overweight children.

Gallstones. The incidence of gallstones is significantly higher in obese women and men. The risk for stone formation is also high if a person loses weight too quickly. In people on ultra-low calorie diets, gallstones may be prevented by taking ursodeoxycholic acid (Actigall).

Click the icon to see an image of gallstones.

People who are obese and nap tend to fall asleep faster and sleep longer during the day. At night, however, it takes them longer to fall asleep, and they sleep less than people with normal weights. In an apparent vicious circle, studies have suggested that obesity not only interferes with sleep but that sleep problems may actually contribute to obesity.

Sleep Apnea. Obesity, particularly the apple shape, is strongly associated with sleep apnea, which occurs when the upper throat relaxes and collapses from time to time during sleep. This collapse temporarily blocks the passage of air. Sleep apnea is increasingly being viewed as a potentially serious health problem, which may lead to complications such as heart disease and stroke. Some studies suggest that among overweight people, those who have sleep apnea have a greater risk of heart disease than those without it. In one study, the more obese a person with sleep apnea was, the higher the pressure on the airway, and therefore the greater the obstruction of the airway. Obstructive sleep apnea may also add to obesity, however, as sleepy people tend to be sedentary. Some studies indicate that treating sleep apnea may help people lose abdominal fat.

Narcolepsy. A small European study found a link between narcolepsy (a sleep disorder characterized by excessive daytime sleepiness with frequent daily sleep attacks) and high BMI.

Depression. A number of studies have reported an association between depression and obesity, particularly in obese women. There may be a number of factors to explain the link. In some cases of atypical depression, people overeat and may gain weight. Overweight people may also become depressed because of social problems and a poor self-image. In these cases, depression usually disappears when people lose weight.

There is evidence, however, that obesity itself may impair levels of tryptophan -- a chemical needed to make serotonin, a brain chemical associated with mental well-being. In one study, even after people lost weight, tryptophan levels were lower than normal.

There does not appear to be any association between depression and obesity in men.

Social Problems. One long-term study reported that overweight young women completed fewer years of school, were 20% less likely to be married, and had 10% higher rates of household poverty than their thinner peer. Obese young men were also less likely to be married, and their incomes were lower than their thinner peers. Nevertheless, studies consistently show that overweight males (both boys and men) are not as severely emotionally affected as females of any age. Women and girls tend to blame themselves for being heavy, while males tend to blame being overweight on outside factors.

Weight Loss and Maintenance

Even modest weight loss can reduce the risk factors for heart disease and diabetes. The simplest (but still difficult) approach to weight loss is reducing calories and exercising at least 150 minutes a week. Behavioral and mental changes in eating habits, physical activity, and attitudes about food and weight are also essential to weight management. For people who are very overweight and cannot lose weight through lifestyle changes, a number of effective weight-loss medications are available. For those with severe obesity, surgical procedures are proving to be very beneficial.

Some Tips for Losing Weight. The following are some general suggestions for dieters:

Start with realistic goals. Diet failure is extremely common, and the odds of significant weight loss are low, particularly in people with the highest weights. People who are able to restrict calories, engage in an exercise program, and get help in making behavioral changes can expect to lose between 5 - 10% of their current body weight. That is generally all that is needed to achieve meaningful health changes. Certainly, the distorted image of a super-thin female shape should not be anyone's goal.
Maintain a regular exercise program, assuming you have no health problems that will stop you. Choose a program that you enjoy. Check with your doctor about any health considerations. [See In-Depth Report #29: Exercise.]
Do not use hunger pangs as cues to eat. A stomach that has been stretched by large meals will continue to signal hunger for large amounts of food until its size reduces over time with smaller meals.
Be honest about how much you eat and start by recording all calories in writing. Studies suggest that when many people report their own calories intake they significantly underestimate their consumption of high-calorie and over-estimate the low-calorie foods. People who do not carefully note everything they eat tend to take in too many calories when they believe they are dieting.
Observe weekend eating. People tend to eat more on the weekends. If it is difficult to monitor all meals during the week, it be may be useful to at least track eating habits during the weekends.
Once the pounds are lost, do your best to keep the healthier weight. Make daily, even hourly, conscious decisions about eating and exercising activities. Such thinking, in many cases, can become automatic and not painful.
Don't give up, even after repeated weight loss failures. Most studies indicate that yo-yo dieting or weight cycling have no bad psychological or physical effects. Repeated dieting also does not harm the body's ability to burn calories efficiently.
Weight loss, in any case, should not be the only or even the primary goal for people concerned about their health. The success of weight loss efforts should be evaluated according to improvements in disease risk factors or symptoms, and by the adoption of healthy lifestyle habits, not just by the number of pounds lost.


Lifestyle	Reduce rate of eating. Keep food records. Eliminate environmental triggers to eating. Identify high-risk situations for overeating. Separate eating from other activities.
Exercise	Face up to emotional barriers to exercise. Understand the link between exercise and weight control. Establish reasonable exercise goals. Develop a plan for regular activity. Add increased activity into daily lifestyle.
Attitudes	Develop reasonable weight-loss goals. Avoid "all or none" thinking. Focus attention away from the scale and toward behavior. Uncouple weight from self-esteem. If you "fall off the wagon," take steps to ensure the situation does not repeat (recover from lapses with constructive action).
Relationships	Understand the key role of social support to health. Identify supportive others. Match personal style to support-seeking activities. Be specific in making support requests. Be assertive but reinforcing in drawing help from others.
Nutrition	Resist the temptation of popular fad diets. Eat with your health in mind; do not concentrate on what should be "off-limits." Eat with moderation in mind. Maximize fiber. Develop a tailored plan.
From Brownell KD. The LEARN Program for Weight Control. 7th ed. Dallas, Tex: American Health Publishing Company; 1998.

Weight Management

There are many approaches to dieting and many claims for great success with various fad diets. To date, although many diets achieve effective immediate weight loss, none has emerged as an effective tool for maintaining healthy weight. The only definite recommendation that can be made about any diet plan is to be sure it includes an exercise program, assuming there are no health problems to forbid it.

The original food pyramid, with four food groups, has been replaced with an updated food guide called "My Pyramid." This illustrates the relative proportions of different foods that make up a nutritious, well-balanced diet and includes exercise.

Calorie restriction has been the cornerstone of obesity treatment. The standard dietary recommendations for losing weight are the following:

As a rough rule of thumb, one pound of fat equals about 3,500 calories. A person could lose a pound a week by reducing daily caloric intake by about 500 calories a day. Naturally, the more severe the daily calorie restriction, the faster the weight loss. Very-low calorie diets have also been associated with better success, but extreme diets can have some serious health consequences.
To determine your daily calories requirements, multiply the number of pounds of ideal weight by 12 - 15 calories. The number of calories per pound depends on gender, age, and activity levels. For instance, a 50-year old woman who wants to maintain a weight of 135 pounds and is mildly active might require only 12 calories per pound (1,620 calories a day). A 25-year old female athlete who wants to maintain the same weight might require 25 calories per pound 2,025 (calories a day).
Fat intake should be no more than 30% of total calories. Most fats should be in the form of monounsaturated fats (such as olive oil). Saturated fats (found in animal products) should be avoided.

Extreme diets of less than 1,100 calories carry health risks. They are also often followed by bingeing or overeating, and a return to the obese state. Such diets often do not have enough vitamins and minerals, which must then be taken as supplements. Most of the initial weight loss is in fluids. Later, fat is lost, but so is muscle, which can account for more than 30% of the weight loss. No one should be on severe diets for longer than 16 weeks, or fast for more than 2 or 3 days. Severe dieting has unpleasant side effects including fatigue, intolerance to cold, hair loss, gallstone formation, and menstrual irregularities. There have been rare reports of death from heart arrhythmias when liquid formulas did not have sufficient nutrients. Pregnant women who excessively diet during the first trimester put their unborn children at risk for birth defects. Of note, those whose diets include a high intake of fluids and much reduced protein and sodium are at risk for hyponatremia, which can cause fatigue, confusion, dizziness, and in extreme cases, coma and death.

This dietary approach requires counting only grams of fat with the goal of achieving 30% or fewer calories from fat. One gram of fat contains nine calories, while one gram of carbohydrates or protein has only four calories. Fat in your diet converts more readily to fat in the body, compared with carbohydrates or proteins. Simply switching to low-fat or skimmed dairy products may be enough for some people.

There are possible drawbacks to this approach:

Some people who reduce their fat intake may not get enough basic nutrients, including vitamins A and E, folic acid, calcium, iron, and zinc. People on low-fat diets should eat a wide variety of foods and take a multivitamin supplement, if appropriate. Calcium deficiencies may be particularly harmful in women at risk for osteoporosis.
Many people start eating foods with too many carbohydrates, believing that they are not adding calories. No one should use a low-fat diet as an excuse for eating too many carbohydrates, particularly starchy foods and sugar. A high-calorie diet from any source will add pounds.
A small study in Norway found that a diet low in fat and high in carbohydrates ("carbs") increases symptoms of psychological distress, such as depression and anger. The study compared three different diets that had varying amounts of fat and carbohydrates in each. The diets contained the same amount of calories, but differed in the percentage and type of fat. People on the low-fat, high-carbohydrate diet reported more anger and depression compared with the other two diets.
Replacing fatty foods, such as cakes, cookies, and chips, with their commercial "low-fat" counterparts does not constitute a low-fat diet. These foods generally contain more sugar and hence calories, not to mention other ingredients, which have virtually no nutritional value. In fact, a 2002 study suggested that increasing sugar may, over time, reduce levels of HDL ("good") cholesterol.
Very low-fat diets may increase the risk for stroke from hemorrhage in the brain.

Some fat in a diet is essential. It should come from plant oils and fish, however, and not from animal products or hardened oils, such as margarine. Trans-fatty acids, found in hardened oils, are actually more of a risk factor for obesity than saturated fats from animal products, although both should be avoided.

Fiber and Complex Carbohydrates. In all cases, complex carbohydrates found in whole grains and vegetables are preferred over those found in starch-heavy foods, such as pastas, white-flour products, and potatoes. Fiber is an important component of many complex carbohydrates. Fiber is almost always found only in plants, particularly vegetables, fruits, whole grains, nuts, and legumes (beans and peas). One exception is chitosan, a dietary fiber made from shellfish skeletons. Fiber cannot be digested but passes through the intestines, drawing water with it, and is eliminated as part of feces content. The following are specific advantages from high-fiber diets (up to 55 grams a day):

Insoluble fiber (found in wheat bran, whole grains, seeds, nuts, and fruit and vegetable peels) has been associated with weight loss. Studies also suggest that diets rich in fiber from whole grains reduce the risk for type 2 diabetes.
Soluble fiber (found in dried beans, oat bran, barley, apples, citrus fruits, and potatoes) has important benefits for the heart, particularly for achieving healthy cholesterol levels and possibly benefiting blood pressure as well. Simply adding breakfast cereal to a diet appears to reduce cholesterol levels. People who increase their levels of soluble fiber should also increase water and fluid intake.

High-protein, low carbohydrate diets, such as the Atkins and South Beach diets, have been touted as effective ways to produce short-term weight loss. Because of their emphasis on fats and proteins, many experts are concerned about long-term health problems. A report in the March 2006 Lancet linked the Atkins diet to life-threatening complications that caused the death of one woman. The 40-year-old woman had a deadly buildup of acids called ketones in her blood, a condition called ketoacidosis. Ketoacidosis can cause coma and death. Ketones are a known by-product of high protein, low carbohydrate diets. At low levels they can cause nausea, lightheadedness, and bad breath.

The long-term effects of these diets are still unknown. For example, the Atkins diet restricts some vegetables and most fruits, which are known to protect against serious diseases such as heart problems and cancer. The diet may also cause too much calcium to build up in the urine. This can increase the risk for kidney stones and osteoporosis. In addition, high-protein intake, particularly from meat, can be harmful in people with kidney problems. Individuals at risk for kidney stones, or those who have other kidney problems, should not go on high-protein diets without talking to their doctor first. Unfortunately, many people with diabetes are at risk of kidney problems, which could reverse any possible benefits a high-protein diet may bring them. Eating a lot of meat has also been associated with certain common cancers, notably prostate and colon cancers. A 2002 study suggested that such diets during pregnancy may increase the risk for high blood pressure in the child.

Still, significant studies say that such diets improve cholesterol and blood sugar levels. Studies in 2002 and 2003 have indicated that these diets lower blood glucose levels, which can be important in people who are diabetic. The diets also reduce triglyceride levels (unhealthy fat molecules) and increases HDL (" good") cholesterol levels. High triglyceride and low HDL levels are important risk factors for heart disease, and are common in people with type 2 diabetes. Studies are mixed on whether this type of diet reduces overall cholesterol or LDL ("bad") cholesterol levels.

Experts that promote the low carbohydrate approach argue that heart problems from obesity are due to insulin disturbances from sugar imbalances. Therefore, they believe that restricting carbohydrates is the best approach for obesity -- especially for overweight people with diabetes. More research is needed, however, to determine the long-term impact of such diets on health.

High-protein, low-carbohydrate diets include Atkins, Protein Power, Sugar Busters, and Dr. Stillman. The Atkins diet is one of the most popular and has a four-phase program:

Induction. For the first 2 weeks, individuals consume no more than 20 grams of carbohydrates a day. The diet consists of pure protein and fats. There is no fruit, bread, grains, starchy vegetables, or dairy products other than cheese, cream, or butter. This phase is not suitable for children, pregnant women, or anyone with kidney disease.
On-going Weight Loss. After the first phase, individuals continue to lose weight while they increase carbohydrate levels by five grams each day.
Premaintenance. When individuals get close to their weight goal, they add another 10 grams of carbohydrates per day as long as they do not begin to gain weight. Weight loss is very slow at this time, but the individual is now getting used to maintenance.
Maintenance. Lifetime maintenance is usually between 40 and 100 grams of carbohydrates a day, depending on steady weight level.

Anyone who chooses this diet should prefer fish or soy products to meat as protein sources. Fish may reduce leptin, a hormone associated with fat storage and heart diseases, and would be the best protein source. People on this diet should also choose monounsaturated fats (as in olive oil) over saturated fats or trans-fatty acids fat. Patients often need supplements, at least a multivitamin and possibly calcium, chromium, omega-3 fatty acids (found in fish oil), and other supplements.

The South Beach and Zone diets encourage healthy fats. They also allow certain carbohydrates. For example the Zone uses healthy carbohydrates (vegetables and dried beans) and unsaturated fats. The South Beach diet uses carbohydrates that have a lower impact on blood sugar levels. This is called a low-glycemic index. Low-glycemic foods include barley, dried bean and peas, milk, strawberries, and apples. High-glycemic foods include refined grains, white bread, white potatoes, and bananas and other tropical fruits. The glycemic index was developed for use in diabetes -- not for weight loss. Nevertheless, there is some evidence that foods with low glycemic indexes may produce a feeling of fullness and so discourage further eating. As with any high-protein diets, people at risk for kidney stones, or those who have other kidney problems, should avoid these plans.

Replacing fats and sugars with substitutes may help many people who have trouble maintaining weight. In fact, in one 2003 study, people with type 2 diabetes used the artificial sweetener sucralose and a beta-glucan fat substitute (derived from oats) as part of a low-calorie diet. At the end of the 4 weeks, they achieved better weight, glucose control, and HDL levels than those on a standard diabetic diet.

Fat Substitutes. Fat substitutes added to commercial foods or used in baking deliver some of the desirable qualities of fat, but do not add as many calories. It should be stressed that eliminating all fats from a diet can be harmful to general health.

Fat substitutes include the following:

Stanols. Stanols are plant compounds used in margarines (Benecol, Take Control). Benecol is derived from pine bark and Take Control from soybeans. Two servings a day of either brand, as part of a low-fat, diet can lower LDL and total cholesterol by impairing its absorption in the intestinal tract. Some studies have reported that the use of stanols can allow lower doses of statins (cholesterol lowering medications). Stanols do not appear to block absorption of fat-soluble nutrients or vitamins, as olestra does.
Olestra (Olean) passes through the body without leaving behind any calories from fat. Studies suggest that it improves cholesterol levels and helps people lose weight when it is used to replace a third of normal dietary fats. (Note that simply adding snacks containing olestra does not appear to have any effect on cholesterol or weight loss.) Early reports of cramps and diarrhea after eating food containing olestra have not proven to be significant. Of greater concern is the fact that even small amounts of olestra deplete the body of certain vitamins and nutrients that may help protect against serious diseases, including cancer. The FDA requires that the missing vitamins be added back to olestra products, but not other nutrients. The side health effects, if any, are unknown.
Beta-glucan is a soluble fiber found in oats and barley. Products using this substance (e.g., Nu-Trim) may reduce cholesterol and have additional health benefits.

A number of other fat-substitutes are also available. Although studies to date are not showing any significant side effects, these products' effect on weight control is uncertain, since many of the products containing them may be high in sugar.

Artificial Sweeteners. Many artificial or low-calories sweeteners are available. A 2002 study confirmed that people who consumed artificial sweeteners and reduced their sugar intake weighed less over time than those who took in similar types and amounts of drinks and food containing sugar. It should be noted that using these artificial sweeteners should not give dieters a license to increase their fat intake. Studies indicate that consuming some sugar is not a significant contributor to weight gain, as long as the total amount of calories in the diet is under control. There is some public concern about chemicals used to produce many of these sweeteners, and the side effects seen in studies using rats. Natural low-calories sweeteners are available that may be more acceptable to many people.

Saccharin (Sugar Twin, Sweet n' Low, Sucaryl, and Featherweight). Saccharin has been used for years. Some studies found that large amounts of saccharin cause bladder cancer in rats. However, the rats were fed huge amounts that do not apply to human diets. Currently there is no evidence that saccharin causes cancer in humans.
Aspartame (Nutra-Sweet, Equal, NutraTase). Aspartame has come under scrutiny because of rare reports of nervous system disorders, including headaches or dizziness, associated with its use. People with phenylketonuria (PKU), a genetic condition, should not use it. Studies have not reported any serious health dangers, but some people may be sensitive to it.
Sucralose (Splenda). Sucralose has no bitter aftertaste and works well in baking, unlike other artificial sweeteners. It is made from real sugar by replacing part of the sugar with chlorine. Some people are concerned because chlorinated molecules used in major industrial chemicals have been associated with cancer and birth defects. Over 100 studies have been conducted on sucralose over a 20-year period, with no reports of such risks.
Acesulfame-potassium (Sweet One, SwissSweet, Sunette). It has been used in the U.S. since 1988 with no reported side effects.
Neotame (Neotame). Neotame is a synthetic variation of aspartame, but was developed to avoid its side effects. The association with aspartame has raised some concerns. Studies to date have reported no effects that would cause alarm, and it appears to be safe for general consumption.
D-tagatose (Tagatose). This reduced-calorie sweetener is made from lactose, which is the sugar found in dairy products and other foods. It may be especially beneficial for people with type 2 diabetes. It may also have additional benefits that help the intestinal tract.
Alitame (Aclame) is formed from amino acids, the building blocks of proteins. It has the potential to be used in all products that contain sugar, including baked goods.
Stevioside (Stevia). This is a natural sweetener derived from a South American plant. It is available in health food stores. People with diabetes should avoid alcohol-based forms. It has not been carefully tested.

Other sugar substitutes being investigated include glycyrrhizin (derived from licorice) and dihycrochalcone (derived from citrus fruits).

Some studies have reported good success with meal replacement beverages (Slim-Fast, Sweet Success). They contain major nutrients needed for daily requirements. Each serving typically contains between 200 - 250 calories and replaces one meal. (Note: Using them for all meals reduces calories to a severe extent and can be harmful.)

One study reported that most subjects who had undergone a 12-week weight loss program and then used Ultra Slim Fast supplements as directed for maintenance kept off more than half their weight loss after more than 3 years. A quarter of the subjects were still losing weight.

Medical evidence suggests that a diet rich in magnesium could reduce a person's risk of metabolic syndrome, a cluster of problems including obesity, high blood pressure, and high cholesterol. Metabolic syndrome can lead to diabetes and heart disease. A long-term study of thousands of Americans found that the risk for metabolic syndrome decreased in those who consumed the most magnesium from meals. The findings were published in the journal Circulation.

Commercial and Non-Profit Support Programs for Weight Loss. There are many different types of weight-loss program. (This report cannot address all of the many commercial and nonprofit weight-loss programs currently available, nor can it assess their claims.)

Taking off Pounds Sensibly (TOPS), a nonprofit support organization with many local chapters, is one of the least expensive programs, costing $20 a year.

Most of the commercial programs such as Weight Watchers, Jenny Craig, and NutriSystem offer individual or group support, lifestyle changes and packaged meals. These programs tend to be expensive. There are few well-conducted studies on these programs. One 2003 study reported modest weight loss over 2 years with Weight Watchers compared to a self-help program. There were no differences in heart risk factors.

Cognitive Behavioral Approaches. Most support programs use some form of cognitive-behavioral methods to change the daily patterns associated with eating. They are very useful for preventing relapse after initial weight loss. The following is a typical approach:

The patient first records in a diary all activity related to eating patterns, including the times of day, length of meal, emotional states, companions, and, of course, the kind and amounts of food eaten. Most people -- even professional dieticians, according to one study -- tend to underreport their daily calorie intake. However, writing it down is still a good method for increasing a person's awareness of eating patterns. (One patient said that recording circumstances surrounding relapses was a particularly valuable guide for understanding the stresses leading to her own eating behaviors.)
The patient reviews the diary with a therapist or group to set realistic goals and identify patterns that the patient can change. For instance, if food is normally eaten while watching television, then the patient may be advised to eat in another room instead.
Good eating habits are reinforced by rewards. These rewards are other pleasures that substitute the high calorie consumption and sedentary activities.

Behavioral modification has been shown to be helpful particularly for people who have an overly strong response to the taste, smell, and appearance of food. It also may be useful for binge eaters.

Stress-Reduction Techniques. Stress reduction and relaxation techniques may be helpful for some people with obesity, such as those whose weight is related to night-eating syndrome. [See In-Depth Report #31: Stress.]

Changing Sedentary Habits. Making even small changes in physical activity can expend energy. For example, simply getting up to turn the TV on and off instead of using the remote, and standing (instead of sitting) while talking on the phone may help a person lose up to five pounds a year. Other suggestions include cooking one's own food (instead of eating take-out or fast food), walking to as many places as possible, using stairs instead of escalators or elevators, and gardening. Even fidgeting may be helpful in keeping pounds off, and, in one study, chewing gum increased energy expenditure.

No one should rely on such mild activities, however, for serious weight loss. Only high levels of physical activity -- not just using up energy -- help prevent obesity.

Approach to Exercise. Exercise, which replaces fat with muscle, is the critical companion for any weight control program. In a one-year study, women who regularly averaged 3.5 days (176 minutes) of exercise each week lost significantly more weight than women who did not exercise regularly. Women who exercised more than 195 minutes a week lost nearly 7% of their abdominal fat.

People who exercise are more apt to stay on a diet plan. Exercise improves psychological well-being and replaces sedentary habits that usually lead to snacking. Exercise may even act as a mild appetite suppressant. Moreover, exercise improves overall health even with modest weight loss. In support of this, a British study found that overweight fit individuals had half the death rate of unfit trim individuals.

Be aware, however, that the pounds won't melt off magically. Losing significant weight requires both intensive exercise and calorie restriction. In addition, if a person exercises but doesn't diet, any actual pounds lost may be minimal, because denser and heavier muscle mass replaces fat. Nonetheless, regardless of weight loss, a fit body will look more toned and be healthier. In addition, exercise benefits the heart even with modest weight loss.

The following are some suggestions and observations on exercise and weight loss:

The more strenuous the exercise, the better the chances for short-term and long-term success. With intense exercise, the metabolism continues to burn calories before returning to its resting level. This state of elevated metabolism can last for as little as a few minutes after light exercise to as long as several hours after prolonged or heavy exercise.
Of the standard aerobic machines, the treadmill burns the most calories. It may be particularly effective when used in short multiple bouts during the day. In fact, frequent exercise sessions as short as 10 minutes in duration (about four times a day) may be the most successful exercise program for obese people.
Resistance, or strength, training is excellent for replacing fat with muscles. It should be performed two or three times a week.
As people slim down, their initial level of physical activity becomes easier and they burn fewer calories per mile of walking or jogging. The rate of weight loss slows down, sometimes discouragingly so, after an initial dramatic head start using diet and exercise combinations. People should be aware of this phenomenon and keep adding to their daily exercise program.
As people age, they also need to exercise more to keep off the same amount of weight.
Changes in fat and muscle distribution may differ between men and women as they exercise. Men tend to lose abdominal fat (which lowers their risk for heart disease faster than reducing general body fat). Exercise, however, does not appear to have the same effect on weight distribution in women. In one interesting study, women in aerobic and strength training programs lost fat in their arms and trunk, but did not gain muscle tissue in these regions.

Warning Note. Because obesity is one of the risk factors for heart disease and diabetes, anyone who is overweight must discuss their exercise program with a doctor before starting. Sudden demanding exercise, in such cases, can be very dangerous. [See In-Depth Report #29: Exercise.]

Medications

There are several different drugs used for weight loss. Unless specifically instructed by a doctor, people should use non-drug methods for losing weight. Except under rare circumstances, pregnant or nursing women should never take diet medications of any sort, including herbal and over-the-counter remedies.

A 2001 study reported that 7% of American adults use nonprescription weight-loss products. People must be cautious when using any weight-loss medications, including over-the counter diet pills and herbal or so-called natural remedies. Buying unverified products over the Internet can be particularly dangerous.

Green tea. Perhaps the best alternative advice for people who are overweight is to drink tea. Studies have indicated that regular tea drinking is associated with lower weight, particularly in people who drink it for years. Green tea specifically has been associated with increased energy expenditure. One study reported that people who took a green tea extract (Exolise) lost weight and reduced their waist size. Better evidence is needed to confirm the results on this supplement.

Thermogenic Approach to Weight Loss. An approach to weight loss called thermogenic (also hepatothermic) therapy is based on the idea that certain natural compounds have properties that enable the liver to increase energy in the cells and stimulate the metabolism. Theoretically, the result would be fat loss. Among the natural substances used in such products are EPA-rich fish oil, sesamin, hydroxycitrate, pantethine, L-carnitine, pyruvate, aloe vera, aspartate, chromium, coenzyme Q10, green tea polyphenols, aloe vera, DHEA derivatives, cilostazol, diazoxide, and fibrate drugs.

Nearly all the current over-the-counter dietary aids contain some combination of these ingredients. There is no evidence that any of these ingredients can produce weight loss, and some may even have harmful effects.

Chromium is a common ingredient in many diet supplements (e.g., Xenadrine, Dexatrim, Acutrim Natural, Twinlab Diet Fuel). It is claimed to specifically promote fat loss, rather than lean muscle loss. Some evidence suggests that niacin-bound chromium may improve insulin sensitivity. On the negative side, animal studies have suggested that chromium may have damaging effects on genetic materials in cells. This could cause sterility.

Ephedra, Ephedrine, and Ma Huang. The FDA does not allow the sale of drugs that contain ephedrine. In May 2004, the FDA banned the sale of dietary supplements that contain ephedra (also called Ma Huang). Ephedra has been linked to serious side effects, including strokes and heart attacks.

Brazilian Diet Pill. The US Food and Drug Administration (FDA) is warning consumers not to buy a product known as the "Brazilian diet pill." This product is labeled as a dietary supplement, but contains several chemicals found in powerful prescription drugs. The products are also known as Emagrece Sim and Herbathin dietary supplements.

Conjugated Linoleic Acid (CLA). Conjugated linoleic acid is found in many dietary products (e.g., Biosculpt Liquid, Body Success, GNC Optibolic Body Answers Dietary Formula). There is no evidence that it produces weight loss. Furthermore, there is some concern that CLA might increase insulin resistance and a dangerous inflammatory response in people with obesity.

Tiratricol. Over-the-counter products containing tiratricol, a thyroid hormone, have been sold for weight loss. Such products may increase the risk for thyroid disorders, heart attack, and stroke.

Laxative Actions in Natural Substances. Many dietary herbal teas contain laxatives, which can cause gastrointestinal distress, and, if overused, may lead to chronic pain, constipation, and dependency. In rare cases, dehydration and death have occurred. Some laxative substances found in teas include senna, aloe, buckthorn, rhubarb root, cascara, and castor oil.

Guar Gum. Some fiber supplements containing guar gum have also caused obstruction of the gastrointestinal tract.

Chitosan. Chitosan, a dietary fiber from shellfish, prevents a small amount of fat from being absorbed in the intestine. Well-conducted studies, however, have not found it to be effective. Products containing it include Cheat & Lean Fat Blocker, Natrol, Chroma Slim, and Enforma. People who are allergic to shellfish should not take these supplements.

Plantain. Dietary remedies that list the ingredient plantain may contain digitalis, a powerful chemical that affects the heart. NOTE: This substance should not be confused with the harmless banana-like plant also called plantain.

Orlistat (Xenical) can help about one-third of obese patients with modest weight loss, and can assist in long-term maintenance of weight loss. It works by slowing the absorption of fat (by about 30%) in the intestine. Studies indicate that between 50 - 80% of patients can achieve weight loss of 5% or greater, depending on other lifestyle changes. However, many people regain a significant portion of this weight back within 2 years. It does not work for all patients, however. In one survey of patients who took it, 10% gained weight or did not lose any, and 43% lost less than 5%. Nevertheless, orlistat may delay or even prevent the onset or progression of diabetes and improve cholesterol levels, regardless of weight loss.

The drug can cause gastrointestinal problems and may interfere with absorption of the fat-soluble vitamins A, D, and E and other important nutrients. The most unpleasant side effect is oily leakage of feces from the anus. Restricting fats can reduce this effect. People with bowel disease should probably avoid it. In spite of these side effects, most patients are able to tolerate this agent.

In February 2007, the FDA approved an over-the-counter (OTC) version of orlistat. It will be sold under the name alli, and will be available at half the prescription strength of Xenical. Those eager to use the new pill should consider its cost and modest benefits compared with its side effects, most commonly oily diarrhea. This pill, which prevents fat absorption from food, also increases the risk of not absorbing important nutrients from food while using it. The FDA recommends taking a daily multivitamin supplement when using alli.

Sibutramine (Meridia) helps balance the brain chemicals serotonin and norepinephrine. This helps increase metabolism, causes a feeling of fullness, and increases energy levels. It may be particularly useful for binge-eaters. Studies indicate that sibutramine is effective in achieving weight loss, although the weight loss slows considerably after the first 3 months. The drug also appears to improve cholesterol and lipid (fat) levels, and may have other effects that benefit the heart.

Side effects of sibutramine are common. They include dry mouth, constipation, and insomnia. In one study, almost half the patients dropped out as a result of these side effects. There have been reports of increases in heart rate and blood pressure while taking this medication, although a 2001 study indicates that blood pressure stabilizes over time.

At this time, people who have a history of high blood pressure, stroke, heart disease, or arrhythmias should not take this drug. People taking decongestants, bronchodilators (such as for asthma), monoamine oxidase inhibitors, or serotonin reuptake inhibitors should also avoid sibutramine.

Phentermine and Other Sympathomimetics. Sympathomimetics are drugs that act like the stress hormone (and chemical messenger) norepinephrine. These medications act as stimulants in the brain. Some are approved for treating obesity, but only for short-term use. They include:

Phentermine (Ionamin, Adipex-P, Fastin)
Benzphetamine (Didrex)
Phendimetrazine (Adipost, Bontril, Melfiat, Plegine, Prelu-2, Statobex)

Phentermine is the most commonly prescribed appetite suppressant, and is less expensive than orlistat or sibutramine. Its effects are not long lasting, however. It can also raise blood pressure. In addition, phentermine is associated with depression, which is already a problem in many cases of obesity. A combination (Phen-Pro) containing phentermine and the antidepressant fluoxetine (Prozac) is being investigated to help reduce this problem. Note: Neither phentermine nor such combinations are associated with the heart problems linked to the previous phentermine combination known as Fen-Phen (phentermine and fenfluramine).

Amphetamines. The amphetamines dextroamphetamine (Dexedrine), methamphetamine (Desoxyn), and phenmetrazine (Pleudin) are powerful stimulants. They were used most often in the past but are no longer prescribed for weight loss. These drugs improve mood and produce some modest weight loss over the short term, but carry serious risks of addiction, agitation, and insomnia.

Rimonabant. Rimonabant (Accompli) belongs to a new class of drugs called selective CB1 blockers. The drug is designed to block receptors in the brain associated with the regulation of eating. Rimonabant also targets receptors in fat tissue. The Rimonabant in Obesity-Lipids (RIO-Lipids) study looked at how rimonabant affected metabolic risk factors in high-risk overweight or obese patients with blood fat disorders. The study involved more than 1,000 participants. The findings, published in the November 2005 New England Journal of Medicine, said that people who took the drug significantly reduced their body weight and size of their waist.

Earlier studies involving the drug reported that obese patients treated with 20 mg of rimonabant lost significantly more weight and inches from their waist than patients who received placebo. The drug also appeared to have beneficial effects on raising HDL ("good") cholesterol levels.

Note: Fake rimonabant has been found for sale on several web sites. Patients should be aware that this drug is still experimental, and rimonabant is not available for sale. Buying and taking counterfeit drugs can have serious health consequences. In addition, an FDA advisory panel in April 2007 rejected the drug, citing fears it may cause psychiatric problems and seizures in some patients.

Axokine. Axokine is a type of drug called a ciliary neurotrophic factor. It signals the brain to suppress one's appetite. It is proving to be effective in achieving weight loss, and also improves cholesterol, lipid, and glucose levels regardless of food intake. It could be particularly helpful for people with type 2 diabetes. Early study results found that severely obese patient who took the drug lost more weight than those who took a dummy pill (placebo). Nearly half (46%) of patients who took the drug lost at least 10 pounds, compared to 5% of those who received the placebo. Study participants tolerated the drug well. There were no reports of serious side effects.

Zonisamide. Zonisamide (Zonegran) is an anti-seizure medication that is also being investigated for weight loss. In one study, patients who took it lost more weight than those on placebo. Zonisamide increases the risk for kidney stones, which can be reduced with increased fluid intake and citrate. It has also been associated with reduced sweating and a sudden rise in body temperature, especially in hot weather. Other side effects include dizziness, forgetfulness, headache, and nausea.

Topiramate. Topiramate (Topamax) is another anti-seizure medication being investigated for weight reduction. Three clinical trials have reported that patients given topiramate lost more weight than those receiving placebo. Weight loss was sustained for up to 1 year. The drug is also being studied for binge-eating disorders associated with obesity.

Other Treatments

Surgical procedures for obesity may be appropriate for some dangerously obese people, and may reduce heart problems and many of the risks associated with obesity. These risks include high blood pressure, sleep apnea, and diabetes. In fact, some evidence suggests that surgery may provide much greater control of weight and diabetes than nonsurgical weight-loss methods. Studies are reporting significant reductions in diabetes, and the need for diabetic medications, after surgery. Other medical conditions that often improve after surgery include heartburn, arthritis, and other joint and circulation problems.

Bariatric surgeries produce weight loss through one of two approaches:

Restrictive Banding Procedures. These procedures restrict the amount of food by closing off parts of the stomach with bands.
Malabsorptive Bypass Procedures. This approach restricts the amount of food and also reduces absorption by using a bypass of parts of the intestine.

The malabsorptive procedures are more successful in achieving weight loss than the banding approach, but they carry a greater risk for nutritional deficiencies.

Most people who have bariatric surgery lose about two-thirds of excess weight within 2 years. In addition, diseases associated with obesity (such as diabetes, high blood pressure, sleep apnea, joint pain, and incontinence) often improve.

Researchers at the Mayo Clinic looked at records from patients who had the surgery between 1990 and 2003. They found that those who had bariatric surgery reduced their risk of cardiovascular events such as a heart attack much more than those who lost weight without surgery. The findings were published in the September 2005 Mayo Clinic Proceedings.

Other studies have shown that even though most patients maintain significant weight loss, the majority regain about to 10% of their weight. Patients must still develop a healthy life style and be calorie conscious after the operation. Follow-up must be life-long.

Any surgical candidate must have failed consistently in losing weight through less invasive methods. Experts recommend bariatric surgery only for the following:

Those whose BMI is above 40 (about 100 pounds overweight)
Those with BMIs of over 35 who have type 2 diabetes or serious obesity-related medical problems
Those with severe obesity that interfered with employment, normal physical activity (e.g., walking), and important relationship

About a third of people who undergo these procedures achieve normal weight, and 80% experience some weigh loss. They are less successful than the bypass procedures, but carry a lower risk of nutritional deficiencies.

Vertical Banded Gastroplasty. Vertical banded gastroplasty (VBG) was the most common restrictive procedure. It involves creating a hole through both stomach walls and sealing the edges with a staple. This narrows the stomach, similar to a funnel, and allows only small amounts of food to pass through.

Laparoscopic Gastric Banding. Laparoscopic gastric banding (the Lap-Band) usually does not require a major incision and avoids some of the major complications of gastric bypass:

It employs an adjustable silicone band that is placed around the upper part of the stomach.
A small balloon-like reservoir attached to the band under the abdominal skin contains saline, which can be added or removed to tighten or loosen the band.
The procedure restricts the amount of food a person can eat and gives the feeling of fullness.

The band is removable, if necessary. Studies to date indicate that the intestinal tract returns to normal afterward. Studies, including those done in the elderly, have reported significant weight loss and improved quality of life with the procedure.

Malabsorptive procedures produce greater weight loss than restrictive procedures. Patients generally achieve about two-thirds of their weight loss within 2 years. Furthermore, in a 2003 study, after standard bypass surgery, 83% of patients with type 2 diabetes experienced normal blood glucose levels and the rest had significant reductions.

Roux-en-Y Gastric Bypass Procedure. This is the most common and successful malabsorptive surgery in the United States. It involves creating a small stomach pouch that serves as a reservoir and restricts food intake. The pouch eventually holds up to 3 ounces of food and has a small outlet that delays emptying and causes a feeling of fullness. Then the surgeon creates a Y-shaped section in the small intestine that attaches to the pouch. This section allows food to bypass the lower stomach and upper part of the intestine. One 2003 study reported that this procedure was associated with significant weight loss, and 80% of patients with type 2 diabetes were able to reduce their medications. A more recent study, published in the March 14, 2006, issue of Archives of Surgery, found that gastric bypass surgery also helps lower the blood pressure of very obese patients.

The procedure produces greater and more sustained weight loss than banding procedures, but it is also more complicated, and carries a higher risk of nutritional deficiencies. Laparoscopy techniques, which are less invasive, are now preferred over open surgery. They achieve equally good results with fewer complications.

Biliopancreatic Diversion. This procedure is more complicated and removes portions of the stomach. The pouch that is created attaches directly to the lower part of the small intestine. It poses a higher risk for nutritional deficiencies than other procedures and is not used as often.

Click the icon to see an image of gastric bypass surgery.

General Side Effects and Complications. Side effects and complications of bariatric procedures are common, and up to 25% of patients require corrective or repeat procedures. After any of these procedures people must chew all their food carefully, and they cannot eat large amounts of food at one time. If patients do not follow these guidelines, they will experience nausea, abdominal distress, or both.

Complications from any bariatric procedure includes the following:

Vomiting: This is the most common complication, and it is most common with banding procedures.
Nutritional deficiencies: There is a strong risk of nutritional deficiencies, particularly with malabsorptive operations. This complication can lead to anemia and increase the risk of bone loss and osteoporosis. Taking enough mineral and vitamin supplements is important after bariatric surgery.
Deep-vein thrombosis: There is a significant risk for deep-vein thrombosis (blood clots in the veins).
Abdominal hernia: This is another common complication. Newer, laparoscopic techniques do not carry this risk, but not all individuals are candidates for this less-invasive approach.
Rapid weight loss after surgery: This complication puts people at high risk for gallstones.
Women who wish to be pregnant should wait until their weight has stabilized. Rapid weight loss and nutritional deficiencies can harm the fetus.

People at highest risk for complications are those with heart or lung problems, severe obesity, and a history of abdominal surgeries. The mortality rate from bariatric surgeries is 0.2%, which is lower than the morality rates from severe obesity itself. Other surgical variations and less invasive techniques using laparoscopy have been developed.

Specific Complications of Restrictive Banding Procedures. Nausea, vomiting, or both occurs in half the patients, and severe heartburn occurs in a third. Device-related complications include band slippage, pouch dilation (widening), or both in nearly a quarter of patients, and obstruction in 12% of patients. Very serious complications are rare, but include blood clots, bleeding, infection, pneumonia, and perforation (tearing) of the stomach.

Specific Complications of Malabsorptive Bypass Procedures. Vomiting often occurs. Nutritional deficiencies occur more often in these procedures. The so-called dumping syndrome is a common unpleasant side effect, which occurs when food waste moves too quickly through the intestine. Symptoms include nausea, weakness, sweating, and faintness (particularly after eating sweets).

Spot Exercising. Anyone seeking to lose weight must expect that the results may not be as cosmetically satisfying as one would wish. Spot exercising (training particular areas of the body) is ineffective in reducing fat in specific locations because exercise draws on fat stores throughout the body. Gimmicky devices such as bust developers, vacuum pants, and exercise belts do absolutely nothing to reduce fat or add bulk in specific locations. Electrical pads wrapped around the waist, arms, or thighs were reported to cause burns and fires.

Cellulite-Removal Creams. Many women try to reduce fat in their thighs (cellulite) with creams that contain aminophylline (Skinny Dip, Thermojetics Body Toning Cream, Smooth Contours). Studies provide no evidence that these creams are effective. Their apparent effect on fat may simply be from narrowing blood vessels and forcing water from the skin, which could be dangerous for people with blood flow problems.

Endermologie. Endermologie uses motorized rollers and regulated suction to smooth out cellulite. In one study, about 28.6% of patients reported improved appearance after using it.

Liposuction. Liposuction eliminates fat in specific areas, such as the abdomen, thighs, buttocks, or knees. Special instruments are inserted through the skin into the pockets and suction is used to move the fat, break it up, and remove it. Small tubes may be used to drain blood and fluid during the first few days. The pain after the operation can be severe and often the skin does not contract, resulting in a flabby look. Complications can include burns from the vibrators, bruising, blood clots, and bleeding. Weight gain generally tends to develop in other locations after the operation. Some doctors are using this procedure in overweight people with diabetes to remove abdominal fat. Although there is no proof that it has an effect on diabetes, some experts believe the procedure deserves attention.

Liposuction is not recommended for major weight loss.

Resources

www.healthierus.gov/dietaryguidelines -- Dietary Guidelines for Americans 2005
www.naaso.org -- North American Association for the Study of Obesity
www.eatright.org -- American Dietetic Association
www.nutrition.gov. -- Nutrition.gov
www.asbs.org -- American Society for Bariatric Surgery
www.cnpp.usda.gov -- Center for Nutrition Policy and Promotion
http://fnic.nal.usda.gov -- Food and Nutrition Information Center
www.americanheart.org -- American Heart Association
www.nationaleatingdisorders.org -- National Eating Disorders Organization
www.aabt.org -- Association for Advancement of Behavior Therapy
www.fda.gov -- Food and Drug Administration
http://win.niddk.nih.gov -- Weight-Control Information Network

References

US Food and Drug Administration FDA Approves Orlistat for Over-the-Counter Use. Rockville, MD: National Press Office; February 7, 2007.

Ogden CL, Carroll MD, Curtin LR, McDowell MA, Tabak CJ, Flegal KM. Prevalence of overweight and obesity in the United States, 1999-2004. Journal of the American Medical Association. 2006; 295:1549-1555.

National Center for Health Statistics. Chartbook on Trends in the Health of Americans. Health, United States, 2005. Hyattsville, MD: Public Health Service. 2005

National Institute of Diabetes and Digestive and Kidney Diseases - Weight-control Information Network. Statistics Related to Overweight and Obesity. Available online.

National Center for Health Statistics. Prevalence of Overweight Among Children and Adolescents: United States, 2003-2004.

Morino M, Toppino M, Bonnet G, Rosa R, et al. Laparoscopic vertical banded gastroplasty for morbid obesity. Assessment of efficacy. Surg Endosc. 2002 Nov;16(11):1566-72.

Brethauer SA, Schauer PR, Chand B. Risks and benefits of bariatric surgery: Current evidence. Cleveland Clinic Journal Of Medicine. 2006 Nov; 73(11): 993-1007.

Rosenthal RJ, Szomstein S, Kennedy CI, et al. Laparoscopic surgery for morbid obesity: 1,001 consecutive bariatric operations performed at The Bariatric Institute, Cleveland Clinic Florida. Obes Surg. 2006 Feb;16(2):119-24.

He K, Liu K, Daviglus ML, et al. Magnesium Intake and Incidence of Metabolic Syndrome Among Young Adults. Circulation. 2006: Published online before print. March 27, 2006.

Chen TY, Smith W, Rosenstock JL, Lessnau KD. A life-threatening complication of Atkins diet. Lancet. 2006 Mar 18;367(9514):958.

Lopez-Jimenez F, Bhatia S, Collazo-Clavell ML, Sarr MG, Somers VK. Safety and efficacy of bariatric surgery in patients with coronary artery disease. Mayo Clin Proc. 2005 Sep;80(9):1157-62.

Sidhaye A, Cheskin LJ. Pharmacologic treatment of obesity. Adv Psychosom Med. 2006;27:42-52.

Fernstrom JD, Courcoulas AP, Houck PR, Fernstrom MH. Long-term changes in blood pressure in extremely obese patients who have undergone bariatric surgery. Arch Surg. 2006 Mar;141(3):276-83.

Despres JP, Golay A, Sjostrom L; Rimonabant in Obesity-Lipids Study Group. Effects of rimonabant on metabolic risk factors in overweight patients with dyslipidemia. N Engl J Med. 2005 Nov 17;353(20):2121-34.

Lanningham-Foster L, Nysse LJ, Levine JA. Labor saved, calories lost: the energetic impact of domestic labor-saving devices. Obes Res. 2003 Oct;11(10):1178-81.

Review Date:
6/14/2007
Reviewed By:
A.D.A.M. Editorial Team: Greg Juhn, M.T.P.W., David R. Eltz, Kelli A. Stacy. Previously reviewed by Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital (4/30/2007).

A.D.A.M. Copyright

adam.com

Osteoporosis

FitSugar — Wed, 08 Oct 2008 17:34:56 -0700

In This Report

Highlights
Introduction
Causes
Symptoms
Fractures
Risk Factors
Diagnosis
Lifestyle Changes
Medications
Treatment
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Drug Approvals

In 2007, the Food and Drug Administration (FDA) approved zoledronic acid (Reclast) for postmenopausal osteoporosis treatment. Zoledronic acid is given as an injection once a year. A 2007 study in the New England Journal of Medicine indicated that zoledronic acid can significantly reduce the risk of spine, hip, and other fractures.
In 2007, the FDA approved raloxifene (Evista) for prevention of breast cancer in postmenopausal women with osteoporosis and postmenopausal women at high risk for breast cancer. Raloxifene was previously approved for prevention and treatment of osteoporosis.

Calcium and Vitamin D for Osteoporosis Prevention

In 2007, the Food and Drug Administration proposed allowing manufacturers of food and supplements to put a health claim on their products stating that the combination of calcium and vitamin D can reduce the risk of osteoporosis.
In 2007, the National Osteoporosis Foundation updated its daily intake guidelines to recommend 1,200 mg of calcium, and 800 - 1,000 IU of vitamin D3, for adults age 50 and older.
Calcium plus vitamin D is effective in preventing osteoporosis in people age 50 years and older, according to a 2007 review in the Lancet. The researchers found that a minimum of 1,200 mg of calcium and at least 800 IU of vitamin D per day gave the most protection.

Fosamax: Taking a Break (Without Breaking a Bone)

Women at low risk for fracture may be able to temporarily stop taking alendronate (Fosamax) after 5 years, suggests a 2006 study in the Journal of the American Medical Association.

Antidepressants and Osteoporosis Risk

Selective serotonin reuptake inhibitors (SSRIs), the most commonly used class of antidepressants, may increase the risk for bone loss in both older men and women, according to several studies published in 2007 in the Archives of Internal Medicine. SSRIs include fluoxetine (Prozac), sertraline (Zoloft), and paroxetine (Paxil). The researchers did not find that other types of antidepressants are associated with reduced bone mineral density.

Introduction

Osteoporosis is a disease of the skeleton in which bones become brittle and prone to fracture. In other words, the bone loses density. Osteoporosis is diagnosed when bone density has decreased to the point where fractures occur with mild stress.

The skeleton consists of groups of bones which protect and move the body.

Until a healthy person is around age 40, the process of breaking down and building up bone by cells called osteoclasts and osteoblasts is a nearly perfectly coupled system, with one phase stimulating the other. As a person ages, or in the presence of certain conditions, this system breaks down and the two processes become out of sync. The reasons why this occurs during aging are not clear. Some individuals have a very high turnover rate of bone, some have a very gradual turnover, but the breakdown of bone eventually overtakes the build-up.

The Function of Bones. The skeleton has a dual function:

It provides structural support for muscles and organs.
It also serves as a depot for the body’s calcium and other essential minerals, such as phosphorus and magnesium.

The skeleton holds 99% of the body’s calcium. The remaining 1% circulates in the blood and is essential for crucial bodily functions, ranging from muscle contraction to nerve function to blood clotting.

Bone Turnover: the Breakdown and Growth of Bones. Like other organs in the body, bone tissue is constantly being broken down and reformed again. This turnover is necessary for growth, for repair of minor damage that occurs from everyday stress, and for the maintenance of a properly functioning body. Two essential cells are involved in this process:

Osteoblast cells are produced by bone cells and are the bone builders. They rebuild the skeleton, first by filling in the holes with collagen, and then by laying down crystals of calcium and phosphorus.
Osteoclast cells are formed from certain blood cells and are responsible for the breakdown, or resorption, of the skeleton. These cells dig holes into the bone and release the small amounts of calcium into the bloodstream that are necessary for other vital functions.

Each year, about 10 - 30% of the adult skeleton is remodeled in this way. The bone build up (formation)-break down (resorption) balance is controlled by a complex mix of hormones and chemical factors. If bone resorption occurs at a greater rate than bone build up, your bone loses density and puts you at risk for osteoporosis.

In women, estrogen loss after menopause is associated with rapid resorption and loss of bone density. This group, then, is at highest risk for osteoporosis and therefore for fracture.

There are two primary kinds of osteoporosis: type I and type II:

Type I. Type I, or high turnover, osteoporosis occurs in 5 - 20% of women, most often between the ages of 50 and 75. This is because of the sudden postmenopausal decrease in estrogen levels, which results in a rapid depletion of calcium from the skeleton. This is associated with fractures that occur when the vertebrae compress together, causing a collapse of the spine. It is also associated with fractures of the hip, wrist, or forearm caused by falls or minor accidents. Women have a higher risk for type 1 osteoporosis than men.
Type II. Type II, or low turnover, osteoporosis (also known as age-related or senile osteoporosis) results when the process of resorption and formation of bone are no longer coordinated, and bone breakdown overcomes bone building. (This occurs with age in everyone to some degree.) Type II osteoporosis affects both men and women and is primarily associated with leg and spinal fractures. Older women can have both type I and type II osteoporosis.

Click the icon to see an image of a compression fracture.

What determines the existence of osteoporosis, whether type I or type II, is the amount of calcium left in the skeleton and whether it places a person at risk for fracture. Someone who has exceptionally dense bones to begin with will probably never lose enough calcium to reach the point where osteoporosis occurs, whereas a person who has low bone density could easily develop osteoporosis despite losing only a relatively small amount of calcium.

Secondary osteoporosis is caused by other conditions, such as hormonal imbalances, diseases, or medications (such as corticosteroids or anti-seizure drugs).

Click the icon to see an image of osteoporosis.

Causes

Because the patterns of reforming and resorbing bone often vary from patient to patient, experts believe several different factors account for this problem. Important chemicals (such as estrogen, parathyroid hormone, and vitamin D) and blood factors that affect cell growth are involved with this process. Changes in levels of any of these factors could play a role in the development of osteoporosis.

Although ordinarily associated with women, sex hormones play a role in osteoporosis in both genders, most likely by controlling the birth and duration of life of both osteoclasts (bone breakers) and osteoblasts (bone builders).

Women and Estrogen. Experts are still puzzled by the rapid decline in bone density after menopause, when a woman’s ovaries stop producing estrogen. Estrogen comes in several forms:

The uterus is a hollow muscular organ located in the female pelvis between the bladder and rectum. The ovaries produce the eggs that travel through the fallopian tubes. Once the egg has left the ovary it can be fertilized and implant itself in the lining of the uterus. The main function of the uterus is to nourish the developing fetus prior to birth.

The most potent form of estrogen is estradiol. Estradiol deficiency appears to be a very strong factor in the development of osteoporosis.
The other important but less powerful estrogens are estrone and estriol.

The ovaries produce most of the estrogen in the body, but it can also be formed in other tissues, such as body fat, skin, and muscle. After menopause, some amounts of estrogen continue to be manufactured in the peripheral body fat. Even though the ovaries have stopped producing estrogens directly, they continue to be a source of the male hormone testosterone, which converts into estradiol.

Estrogen may have an impact on bone density in various ways:

Estrogen’s most important effect on osteoporosis appears to be prevention of bone breakdown (resorption). Some research suggests that estrogen may control the life span of osteoclasts, the cells responsible for bone breakdown.
One study reported that part of estrogen’s beneficial actions may involve maintaining normal levels of vitamin D, an important nutrient in bone protection.

Men and Androgens and Estrogen. In men, the most important androgen (male hormone) is testosterone, which is produced in the testes. Other androgens are produced in the adrenal glands. Androgens are converted to estrogen in various parts of a man’s body, including bone.

Click the icon to see an image of the adrenal glands.

Studies have suggested that the loss of estrogen as well as testosterone may contribute to bone loss in elderly men. In one study, elderly men were first given a drug that blocked their normal hormones and then were given estrogen and testosterone patches. When the estrogen patch was removed, the bone breakdown process accelerated. When both patches were removed, the number of the bone-building cells (the osteoblasts) decreased. In other words, both hormones appeared to be integral to bone function in men.

Low levels of vitamin D and high levels of parathyroid hormone (PTH) are associated with hip fracture in women after menopause:

Vitamin D is a vitamin with hormone-like properties. It is essential for the absorption of calcium into the bone and for normal bone growth. Lower levels result in impaired calcium absorption, which in turn causes an increase in PTH.
Parathyroid hormone (PTH) is produced by the parathyroid glands. These are four small glands located on the surface of the thyroid gland. They are the most important regulators of calcium levels in the blood. When calcium levels are low, the glands secrete more PTH, which then increases blood calcium levels. High persistent levels of PTH stimulate bone resorption (bone loss).

Click the icon to see an image of the benefits of vitamin D.

Click the icon to see an image of the sources of vitamin D.

Click the icon to see an image of the parathyroid glands.

Several studies on family members, including twins, have strongly suggested that genetic factors help determine bone density. Some examples include the following:

Of particular interest are genetic factors that affect vitamin D, a critical nutrient for calcium absorption in the body.
Many studies are looking at abnormalities in genes that may cause deficiencies in estrogen receptors, molecules that help estrogen work on cells. Estrogen is important in maintaining bone density in both men and women.

Corticosteroids. More than 30 million Americans have disorders that are commonly treated using corticosteroid drugs (also called glucocorticoids or steroids). Oral corticosteroids can reduce bone mass in both men and women. It is not clear whether inhaled steroids carry the same risks, but some studies indicate that they may cause bone loss when taken at higher doses for long periods of time. (Children on inhaled steroids may have temporary impaired growth, but they do not appear to be at risk for bone loss.)

Antidepressants. Selective serotonin reuptake inhibitors (SSRIs) -- a class of antidepressants that includes fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft) -- may be associated with bone loss in both older men and women, according to two 2007 studies in the Archives of Internal Medicine. The researchers did not find an increased risk for bone loss with other types of antidepressants.

Diuretics. Diuretics, which are used to treat high blood pressure, have different effects on osteoporosis, depending on the type. Loop diuretics, such as furosemide (Lasix), increase the kidneys’ excretion of calcium, which can lead to thinning bones. Thiazide diuretics, on the other hand, protect against bone loss, but this protective effect ends after use is discontinued.

Contraceptives. Hormonal contraceptives that use progestin without estrogen (such as Depo-Provera injection or other progestin-based contraceptives), can cause loss of bone density. For this reason, the Food and Drug Administration (FDA) recommends that Depo-Provera injections should not be used for longer than 2 years. Some, but not all, studies suggest that combination estrogen-progestin oral contraceptives increase the risk for osteoporosis later in life. Women who take birth control pills should be sure to get adequate calcium and vitamin D from diet or supplements.

Other Medications. Anti-epileptic (anti-seizure) drugs increase the risk for bone loss (as does epilepsy itself). Other drugs that increase the risk for bone loss include the blood-thinning drug heparin, and hormonal drugs that suppress estrogen (such as gonadotropin-releasing hormone agonists). A 2006 study in the Journal of the American Medical Association suggested that long-term (greater than 1 year) use of proton-pump inhibitors (PPIs) may increase the risk for hip fractures. PPIs are used to treat gastroesophageal reflux disease (heartburn) and include omeprazole (Prilosec), lansoprazole (Prevacid), and esomeprazole (Nexium).

Predisposing Medical Conditions. Osteoporosis can be secondary to several other conditions, including alcoholism, diabetes, hyperthyroidism, epilepsy, chronic liver or kidney disease, celiac disease, scurvy, rheumatoid arthritis, leukemia, cirrhosis, gastrointestinal diseases, vitamin D deficiency, hypogonadism (impaired development of reproductive organs), lymphoma, hyperparathyroidism, and rare genetic disorders such as Marfan and Ehlers-Danlos syndrome.

Symptoms

Many people confuse osteoporosis with arthritis and believe they can wait for symptoms such as swelling and joint pain to occur before seeing a doctor. However, the mechanisms that cause arthritis are entirely different from those in osteoporosis. Osteoporosis usually becomes quite advanced before symptoms appear.

All too often, osteoporosis becomes apparent in dramatic fashion: a fracture of a vertebra (backbone), hip, forearm, or any bony site if sufficient bone mass is lost. These fractures frequently occur after apparently minor trauma, such as bending over, lifting, jumping, or falling from the standing position.

Pain, disfigurement, and debilitation are common in the latter stages of the disease. Early spinal compression fractures may go undetected for a long time, but after a large percentage of calcium has been lost, the vertebrae in the spine start to collapse, gradually causing a stooped posture called kyphosis, or a "dowager’s hump." Although this is usually painless, patients may lose as much as 6 inches in height.

Click the icon to see an image of osteoporosis.

Fractures

Bone density loss from osteoporosis is a major cause of disability and death in the elderly, mostly due to subsequent fractures. The lifetime risk of spinal fracture in women is about one in three, and that for hip fracture is one in six. Women at highest risk for fractures are those with low bone density plus a history of fractures, particularly nonviolent fractures.

Click the icon to see an animation about osteoporosis.

Each year, there are an estimated 500,000 spinal fractures, 300,000 hip fractures, 200,000 broken wrists and 300,000 fractures of other bones. About 80% of these fractures occur after relatively minor falls or accidents.

Between 25 - 60% of women older than age 60 develop spinal compression fractures. Studies on men with osteoporosis report that they have a 6% risk for hip fracture and between 16 - 25% risk for any fractures related to osteoporosis.

Click the icon to see an image of a compression fracture.

Click the icon to see an image of a hip fracture.

Unfortunately, studies continue to report inadequate treatment after a fracture. In a major 2003 study, for example, only 8.4% of women who had sustained fractures were tested for osteoporosis. Worse, less than half of these women received any treatment for osteoporosis. Overall, in the study fewer than 4% of men and half of women who had sustained fractures were evaluated and treated according to recommended guidelines. The older a woman was, the less likely she was to have adequate treatment.

Risk Factors for Fracture and Falling. The risk for fracture itself in people with low bone density is compounded by certain features. Having multiple risk factors for osteoporosis itself poses a higher risk for fractures. However, not all older women with osteoporosis develop fractures. There is some evidence that the body partially compensates after menopause by increasing bone strength, which can help offset the risk for fracture.

Falling, of course, is the primary risk factor for fracture. So, additional risk factors for fracture are those that increase the risk for falling. They include:

Having chronic medical problems (emphysema, heart disease, stroke, arthritis, and depression), with the risk increasing with multiple health problems. Such problems may account for 30% of falls in older women.
Taking multiple medications (especially tranquilizers and antidepressants).
Poor physical function, importantly slow gait and reduced muscle strength. Inactivity that results in weak thigh muscles and poor balance particularly puts any older person at risk for fracture and particularly those with low bone density.
Poor concentration or mental impairment.
Impaired vision.
Hazardous environment (such as the presence of throw rugs in the house).

Between 25 - 36% of women who experience a hip fracture die within a year afterward, and about a quarter of the patients require nursing home treatment. The mortality rates after major fractures may be even higher in older men than in older women. Mortality rates after hip fractures declined from the 1960s through the early 1980s, but they have since leveled off. Whether or not medical advances can improve mortality rates in the future, prevention of osteoporosis is extremely important.

Risk Factors

Gender. An estimated 10 million adults in the United States have osteoporosis and another 34 million have low bone mass that places them at risk for developing osteoporosis. A 2004 report from the Surgeon General's office estimates that by 2020, half of all Americans over age 50 could be at risk for this condition. Eighty percent of people with osteoporosis are women. Men start with higher bone density and lose calcium at a slower rate than women, which is why their risk is far lower. Nevertheless, after age 50, bone loss increases and, according to recent studies, more rapidly than previously thought.

Ethnicity. Although adults from all ethnic groups are susceptible to developing osteoporosis, Caucasian and Asian women and men face a comparatively greater risk. About 20% of non-Hispanic white and Asian women older than age 50 have osteoporosis, and over 50% are at risk due to low bone mass. Osteoporosis affects 10% of Hispanic women (49% at risk) and 5% of non-Hispanic black women (35% at risk). Body type can also be a factor. Osteoporosis is more common in women who have a small, thin body frame and bone structure.

Events associated with estrogen deficiencies are the primary risk factors for osteoporosis in women.

Natural and Surgical Causes of Estrogen Deficiency.

Menopause. Within 5 years after menopause, the risk for fracture increases dramatically. Fractures occurring during this period are more likely to occur in the wrist or spine than the hip, but their occurrence is a strong predictor of later severe osteoporosis and hip fracture.
Surgical removal of ovaries.
Missing periods for 3 months or longer.
Never giving birth.
Pregnancy and nursing do not increase the risk for osteoporosis even though during those times calcium is diverted from the mother to the baby. A factor believed to be associated with reduced bone density is elevated at a constant level during nursing, but as the baby is weaned, levels of the factor decline and bone formation is restored.

Female Athlete Triad. In athletes, excessive exercise plays a major role in many cases of anorexia (and, to a lesser degree, bulimia), which in turn increases the risk for low estrogen levels and bone loss. The term "female athlete triad" in fact, is now a common and serious disorder facing young female athletes and dancers and describes the combined presence of the following problems:

Osteoporosis
Amenorrhea (absence or irregular menstruation)
Eating disorders

Some specific risk factors in men include:

Hormonal deficiencies, including both testosterone and estrogen, which occur in older men (although much more slowly than in women). Estrogen deficiencies may also play a major role in osteoporosis in older men. It is unknown yet what normal estrogen levels are in men.
Medical conditions that can reduce testosterone levels, such as prostate cancer treatments, testicular surgery, and mumps.
Hypogonadism, which is a severe deficiency in the primary hormone that signals the process leading to the release of testosterone and other important reproductive hormones.

Of concern, are studies suggesting that men who have osteoporosis and suffer hip fractures are far less likely to be tested and treated for low bone density than are women. In one study, only 27% of men were treated for osteoporosis compared to 71% of women.

Dietary Factors. Diet plays an important role in preventing and speeding up bone loss in men and women. Calcium and vitamin D deficiencies, of course, are important factors in the risk for osteoporosis. Other dietary factors may also be harmful or protective for certain people.

Calcium requires adequate vitamin D in order to be absorbed by the body. In the United States, many food sources of calcium such as milk are fortified with vitamin D.

Click the icon to see an image of the sources of calcium.

Lack of Exercise. Lack of exercise can put thinner people at risk for osteoporosis.

Being Underweight. Being underweight is a risk factor for osteoporosis in men as well as women. (Shortness, thinness, and narrow hips all increase the risk for fracture in people with low bone density.)

Lack of Sunlight. The photochemical effect of sunlight on the skin is a primary source for vitamin D. Bone formation peaks in the summer and bone breakdown increases in the winter. People who avoid sun exposure to prevent skin cancer may be at risk for vitamin D deficiency, particularly it they are elderly.

Click the icon to see an image of the sources of vitamin D.

Smoking. Women who smoke, particularly after menopause, have a significantly greater chance of spine and hip fractures than those who don’t smoke. Men who smoke also have lower bone density.

Diabetes. Diabetes changes bone quality and density and increases the risk for osteoporosis, but the effects differ depending on type:

Type 1 diabetes is associated with a slightly reduced bone density, putting patients at risk for osteoporosis and possibly fracture.
Type 2 diabetes, on the other hand, is associated with an increased bone density. In such cases, the bone quality itself may be impaired, since people with type 2 diabetes are still at higher risk for fractures.

Older patients with any diabetes type are at high risk for falling, which compounds the risk for fracture.

The maximum density that bones achieved during the growing years is a major factor in whether a person goes on to develop osteoporosis. Persons, usually women, who never develop peak bone mass in early life are at high risk for osteoporosis later on. Children at risk for low peak bone mass include children who are:

Born prematurely
Have anorexia nervosa (more common in girls)
Young, highly competitive athletes
Take oral corticosteroid drugs (inhaled steroids, which are common in asthma treatments, appear to pose a very low risk or none at all)
Have certain medical conditions (cystic fibrosis, epilepsy, inflammatory bowel disease, and celiac disease)
Have delayed puberty

Although to a large extent genetics predict bone health, exercise and good nutrition during the first three decades of life (when peak bone mass is reached) are still excellent safeguards against osteoporosis (and countless other health problems).

Diagnosis

About 20 - 30% of Caucasian women in the U.S. can expect to be affected by osteoporosis, including having a spinal fracture, after age 60. Hispanic, Asian, and Native American women have an even higher risk. Nearly all of them are unaware of the condition and so fail to seek a diagnosis. Even worse, studies continue to report inadequate evaluation for osteoporosis even after a fracture.

Evidence suggests that screening for osteoporosis can help prevent fractures. Expert groups now recommend bone density screening for the following people:

All women over age 65.
Any postmenopausal women under 65 years with risk factors for osteoporosis (being thin, being a smoker, having a family history of osteoporosis, corticosteroids use, or any serious high-risk condition, such as hyperthyroidism or early menopause).
Any older men or women who suffer a fracture. (Unfortunately, studies suggest that only a minority of these patients are evaluated and treated for osteoporosis. Men are especially less likely to be tested.)

Whether perimenopausal women should be screened is unclear. (Perimenopause is the period that extends a few years before and after menopause, usually ages 50 - 59.) Some experts believe that women as young as 21 who have strong risk factors for osteoporosis (such as anorexia or absence of menstruation due to over-exercising) should consider being tested. It is also important that older women continue to get bone density tests. A 2006 study found that only 10% of women over age 75 receive bone density screenings, even though they are the age group most likely to have hip fractures.

Bone Densitometry. The standard technique for determining bone density is a form of bone densitometry called dual-energy x-ray absorptiometry (DEXA). DEXA is simple and painless and takes 2 - 4 minutes. The machine measures bone density by detecting the extent to which bones absorb photons that are generated by very low-level x-rays. (Photons are atomic particles with no charge.) Measurements of bone mineral density are generally given as the average concentrations of calcium in areas that are scanned.

A bone density scan measures the density of bone in a person. The lower the density of a bone the higher the risk of fractures. A bone scan, along with a patient's medical history, is a useful aid in evaluating the probability of a fracture and whether any preventative treatment is needed. A bone density scan has the advantage of being painless and exposing the patient to only a small amount of radiation.

Bone mineral density is usually measured at the hip rather than the spine or wrist, which appears to be the most predictive of hip fracture. (Hip fractures are the most dangerous fractures, particularly in women older than sixty.) The bone density in the spine may also be measured. (Spinal bone density in older people however may be misleading. Bone density in this group may increase because of compression on the spinal bones from arthritic changes in the spine. Therefore, bone density measurements may be normal or even high, but the patient may actually be at risk for fracture.)

Click the icon to see an image of a hip fracture.

Ultrasound. Ultrasound techniques measure bone density in the heels, fingers, and leg bones. In early studies, advanced ultrasound techniques, such as quantitative ultrasound (QUS), are promising for improving accuracy in predicting fractures when used with DEXA. Ultrasound itself is less expensive than DEXA and uses no radiation. Ultrasound bone tests are sometimes given at health fairs or other non-medical settings. It should be noted that these results typically vary widely from measurements of the hipbone and are not reliable when used alone.

Quantitative Computed Tomography. Quantitative computed tomography (QCT) scans, a form of CT scans, can provide highly detailed information about spinal density. Radiation doses from this technique are higher than the others. Whether QCT predicts fracture risk accurately is, however, unknown.

Osteoporosis is diagnosed when bone density has decreased to the point where fractures will happen with mild stress, the so-called fracture threshold. This is determined by measuring bone density and comparing the results with the norm. However, low scores on bone density are not very accurate in determining fracture risk without consideration of other risk factors for fracture.

In general, doctors take the following steps to determine osteoporosis:

Bone mineral density ) is measured, typically in the hipbone, using bone densitometry.
Measurements of bone mineral density are given as mg/cm.² This is the average concentration of bone mineral in the areas that are being scanned. In general, bone is normal if results are greater than 833 mg/cm.² Low bone density (osteopenia) is between 833 and 648 mg/cm.² Osteoporosis is diagnosed with results below 648 mg/cm.²

These measurements still do not always indicate the true risk for fracture. The doctor also assesses risk factors and other considerations. The next step is to compare the patient's bone mineral density to normal bone density, which is defined as the average bone mineral density in the hipbones of premenopausal Caucasian women. (This group is used as the basis for the norm because of their high risk and greater proportion in the American population.)

The health professional then uses this comparison to determine her standard deviation (SD) from this norm. Standard deviation results are given as Z and T scores:

A T score gives the standard deviation of the patient in relationship to the norm in young adults. Doctors often use the T-score and other risk factors to determine the risk for fracture.
A Z score gives the standard deviation of the patient in relationship to the norm in her own age group. Z scores may be used to monitor the effects of treatments in women who have been diagnosed with osteoporosis.

For example, the lifetime risks for a younger woman with a specific T-score would be higher than the same scores in an older woman because the younger woman would have a longer time to lose bone density. In general, the T scores in a 55-year-old woman suggest the following degrees of risk for hip fracture.

One standard deviation or less below the norm indicates normal bone mineral density. (This carries a lifetime chance for a hip fracture of up to about 20%, depending on age and other risk factors.)
Between 1 and 2.5 standard deviation s below normal defines osteopenia, which is low bone density. This carries between a 20 - 50% lifetime risk for fracture.
More than 2.5 standard deviation s predicts osteoporosis and over a 60% chance for hip fracture. Additional risk factors increase the risk. They include low weight, smoking, risks for falling, and especially a history of previous fractures. For example, in women 65 years old with low bone density but no adverse factors, the risk for fracture is 4.3% in 1 year and 28.6% over 5 years. In similar women with a previous fracture, the probability of fracture at 1 year is 11% and at 5 years is 71.8%.

Not all older women with osteoporosis develop fractures. There is some evidence that the body partially compensates after menopause by increasing bone strength, which can help offset the risk for fracture. Techniques to measure bone strength may better identify women at higher or lower risk.

Note: Because the standards are based on Caucasian women, they do not necessarily apply to men, children, or to non-Caucasian women. For example, men have a lower risk for fracture at the same standard deviations as women. Researchers are attempting to establish risk guidelines for these groups as well.

Laboratory blood or urine tests for identifying certain markers of bone loss may prove to be useful in certain cases:

High levels of the chemicals deoxypyridinoline and C-telopeptide in the blood may indicate increased risk for hip fracture. These substances are produced when bone is broken down.
A urine test detecting a substance called N-telopeptide may indicate bone loss (although it is not associated with any risk for fracture).

Lifestyle Changes

Because osteoporosis affects such a considerable portion of the female population, total prevention may not be possible, particularly for high-risk groups. Once a woman goes through menopause and more rapid bone depletion occurs, the line between prevention and treatment blurs. Despite their lower risk for osteoporosis, men should also protect their bones with the same healthy lifestyle habits.

Exercise is very important for slowing the progression of osteoporosis. Although mild exercise does not protect bones, moderate exercise (more than 3 days a week for more than a total of 90 minutes a week) reduces the risk for osteoporosis and fracture in both older men and women. Everyone who is in good health should aim for more. Exercise should be regular and life-long. Before beginning any strenuous exercise program, older patients, those at risk or those who have serious medical conditions, should talk to their doctors.

Specific exercises may be better than others, depending on the age group:

Children should begin exercising before adolescence, since bone mass increases during puberty and reaches its peak between ages 20 and 30. Some evidence suggests that exercise may help develop bone mass in teenagers more effectively than high calcium intake. High-intensity exercises may be particularly bone-strengthening in young people. (Such regimes should not be confused with the athlete-triad -- intense competitive exercise, eating disorders, and menstrual irregularities -- that causes osteoporosis in young athletes.)
Weight-bearing exercise applies tension to muscle and bone and, in young people, encourages the body to compensate for the added stress, increasing bone density by as much as 2 - 8% a year. In premenopausal women these exercises are very protective. (Young men need high-intensity exercises to increase bone mass.) Careful weight training is also very beneficial for elderly people, especially women.
Regular brisk long walks improve bone density and mobility and may relieve osteoarthritic pain. High-impact exercises can be very bone-protective in young and middle-aged adults who have no precluding medical or physical conditions. Most older individuals should avoid high-impact aerobic exercises (step aerobics), which increase the risk for osteoporotic fractures. (Older people, particularly women who engage in jumping exercises should do so under supervision.) Although low-impact aerobic exercises such as swimming and bicycling do not increase bone density, they are excellent for cardiovascular fitness and should be part of a regular regimen.
Exercises specifically targeted to strengthen the back help prevent fractures later on in life and can be beneficial in improving posture and reducing kyphosis (hunchback), even in people with existing severe conditions.
Low-impact exercises that improve concentration, balance, and strength, particularly yoga and tai chi, have been found to decrease the risk of falling. In one study, tai chi reduced the risk of falling by almost half.

Exercise plays an important role in the retention of bone density in the aging person. Studies show that exercises requiring muscles to pull on bones cause the bones to retain and possibly gain density.

Click the icon to see an image of osteoporosis.

In 2007, the Food and Drug Administration (FDA) proposed a new health claim for foods and dietary supplements that contain calcium and vitamin D. The FDA’s recommendation will allow manufacturers of these products to state that the combination of calcium and vitamin D can reduce the risk of osteoporosis. Also in 2007, the National Osteoporosis Foundation (NOF) updated its recommendations for getting enough calcium and vitamin D3. The NOF now recommends 1,200 mg of calcium/day and 800 - 1,200 I.U. of vitamin D3/day for adults age 50 and older. (For strong bones, people need enough of both calcium and vitamin D.)

For years, doctors have recommended that women take supplements of calcium plus vitamin D to help maintain bone density and reduce the risk for fractures. Many studies, including a 2007 review in the Lancet, show that a combination of calcium and vitamin D can help prevent osteoporosis. However, a 2006 New England Journal of Medicine study raised some questions about this approach. In the Women’s Health Initiative study, women were randomly assigned to receive either 1,000 mg of calcium carbonate plus 400 IU of vitamin D a day or placebo. The results indicated that daily calcium and vitamin D supplements:

Improve slightly (by 1%) hip bone density
Prevent hip fracture, but only for women who consistently take the supplements. (Another 2006 study supported this finding.)
Do not prevent spine or other types of fractures
Produce a slight increase in the risk of kidney stones

The medical community has differing views on how to interpret these findings. Some doctors recommend that women over age 60 should still consider taking calcium and vitamin D for bone health. Other doctors feel that due to the risks of kidney stones, supplements are beneficial only for women (especially those over age 70) who do not get enough calcium in their diets. Ask your doctor whether or not you should take calcium supplements.

Appropriate Daily Doses. Recommended daily amounts of calcium depend on age and risk factors:

In young people, children ages 3 - 8 should take 800 mg of calcium per day, while children and adolescents ages 9 - 17 need 1,300 mg per day. Teenage girls who do not have enough calcium in their diets should consider taking supplements, which can help build bone density during these critical years.
The standard recommended dose for people over age 50 is about 1,200 mg per day, but actual dosage may be higher or lower depending on risk factors. Even doses of 1,000 mg may help preserve bone in many postmenopausal women without osteoporosis, including during winter months (when bone loss is greatest). In women who have already experienced osteoporosis-related fractures, however, 1,000 mg daily may not add any protective benefits without bone-building medication.
Some experts suggest that all pregnant women, adolescents, and those on corticosteroids take 1,000 - 1,300 mg of calcium every day.
Breast-feeding women should have 2,000 mg per day.

Forms of Calcium Supplements. There are several different kinds of calcium supplements, such as calcium carbonate (Caltrate, Os-Cal, Tums), calcium citrate (Citracal), calcium gluconate, and calcium lactate. Although each kind provides calcium, they all have different calcium concentrations, absorption capabilities, and other actions. Their value in preserving bones depends on many different factors:

Calcium Concentrations. Forty percent of calcium carbonate is actually calcium, whereas calcium citrate is 24% calcium, and calcium gluconate is only 9% calcium.
Calcium Absorption Capabilities. The calcium must also be absorbed from the stomach into the bloodstream. Calcium citrate is better absorbed than many other calcium compounds. It was reported to be the first calcium supplement to preserve bone density after menopause. (Calcium citrate also increases iron absorption. Milk and other calcium compounds tend to reduce iron absorption.) One simple method for testing the absorbency of a particular brand of calcium tablet is to place it in a glass of white vinegar at full strength and check to be sure that it breaks up within 30 minutes. Taking large amounts of antacids can impair calcium absorption. People should take calcium supplements after meals.

Side Effects. Calcium supplements, even at normal doses of about 1,000 mg a day, can increase the risk for kidney stones. People should be careful not to exceed the upper limit of 2,500 mg per day. (Because many commercial foods are now fortified with calcium, this upper limit may be easier to reach than people think.) Calcium may boost the effects of drugs used to treat osteoporosis.

Click the icon to see an image of kidney stones.

Although not a specific side effect of calcium, there has been much public concern about reports of a small amount of lead in calcium supplements. Although exposure to high levels of lead can cause health problems, the amount in such supplements is very small and may pose little or no hazard.

Vitamin D. Vitamin D helps the stomach and the gastrointestinal tract absorb calcium. It also is the essential companion to calcium in maintaining strong bones. Moreover, vitamin D protects against osteoporosis only in combination with calcium.

Click the icon to see an image of the benefits of vitamin D.

Vitamin D is made in the skin using energy from the ultraviolet rays in sunlight. People also can get it from dietary supplements.

As a person ages, vitamin D levels decline. They also fall during winter months and when people have inadequate sunlight. Pollution may also contribute to less sunlight and declining vitamin D levels.

Click the icon to see an image of the sources of vitamin D.

Most current adult guidelines recommend:

400 IU (10 mcg) for people aged 50 - 60.
600 IU (15 mcg) for those over age 70 who do not have sufficient exposure to sunlight. (Evidence suggests that higher doses of vitamin D -- up to 1,000 IU per day -- may help prevent fractures in people with osteoporosis.)

There are various recommendations for daily vitamin D intake. In 2007, the National Osteoporosis Foundation updated its guidelines to recommend 400 - 800 IU of vitamin D3 for adults younger than age 50, and 800 - 1,000 IU of vitamin D3 for adults age 50 and older. Vitamin D3, also called cholecalciferol, is the form of vitamin D that is best for bone health. In addition to supplements, food sources for vitamin D3 include fortified milk, egg yolks, saltwater fish, and liver.

In 2007, the U.S. National Institute of Health’s Office of Dietary Supplements released a report regarding vitamin D and bone health. Researchers were not able to definitely separate the effect of vitamin D from that of calcium, as most clinical trials evaluate the combination of these supplements. The report did indicate that a combination of daily vitamin D3 (700 - 800 IU) and calcium (500 - 1,200 mg) decreases the risks of falls, fractures, and bone loss in elderly people (ages 62 - 85 years).

Sufficient sunlight exposure and drinking milk fortified with vitamin D supply most people’s normal needs for vitamin D. One cup of whole milk provides about 100 IU of vitamin D.

Vitamin D is toxic in doses above 2,000 IU a day. No one should exceed the recommended daily intake of vitamin D except under the direction of a doctor.

Many people could become deficient in vitamin D as they avoid sunlight to prevent skin cancers and instead increase their intake of milk products, such as yogurt and skim milk, which may have little vitamin D. Such individuals may need to take supplements. People with darker skin have a higher risk for vitamin D deficiency than those with lighter skin.

Vitamin D derivatives are being investigated for treating osteoporosis. Calcitriol (Calcijex, Rocaltrol), for example, is a prescription-form of vitamin D that can increase bone mass and decrease the rate of spinal fractures. However, calcitriol increases the risk for high blood calcium levels (hypercalcemia) and requires frequent monitoring.

Vitamin K. Vitamin K has properties that protect bone and prevent fracture. Because intestinal bacteria produce vitamin K, and the vitamin is found in leafy vegetables, deficiencies are rare. Some evidence suggests, however, that people may not be consuming enough of this nutrient. Vitamin K affects blood clotting, and taking supplements is not recommended without first talking to a doctor. Vitamin K2 (menatetrenone), a form of vitamin K, may help prevent fractures in people with osteoporosis.

Click the icon to see an image of the benefits of vitamin K.

Click the icon to see an image of the sources of vitamin K.

Vitamin B12. Studies suggest that people need the right amounts of vitamin B12 and folic acid to maintain their bone mineral density.

Vitamin A. High amounts of dietary vitamin A reduce bone density and may even increase the risk for fracture in postmenopausal women. (A form of vitamin A, retinoic acid, has been found to stimulate bone breakdown.)

The DASH Diet and Low Sodium. Perhaps a good general approach for people at risk for osteoporosis (or almost any adult) is the DASH diet plus sodium (salt) restriction. The DASH (Dietary Approaches to Stop Hypertension) diet is used to help people with hypertension maintain healthy blood pressures. A 2003 study also reported that it might help protect bones and improve cholesterol levels. This diet not only is rich in important nutrients and fiber but also includes foods that contain far more potassium, calcium, and magnesium, than are found in the average American diet. All of these minerals are important for bone protection. The dietary recommendations are as follows:

Avoid saturated fat (although include calcium-rich dairy products that are no- or low-fat). When choosing fats, select monounsaturated oils, such as olive or canola oils. These fats are also found in some fish. Although no one wants to be overweight, even a slight excess of fat helps protect bones. In one study, women who ate more fat in their diet were, on average, better able to absorb calcium than were women who had been put on a low-fat, high-fiber diet.
Choose whole grains over white flour or pasta products. Include nuts, seeds, or legumes (dried beans or peas) daily.
Choose fresh fruits and vegetables every day. Many of these foods are rich in potassium, magnesium, and other minerals that are important for bone (as well as heart) protection.
Choose protein preferably from fish, poultry, or soy products. Soy in combination with fiber-rich foods or supplements may have specific benefits. Oily fish may also be particularly beneficial. They contain omega-3 fatty acids, which have been associated with heart and nerve protection.

Salt Restriction. Reducing salt may protect both the heart and the bones. High sodium intake interferes with calcium retention. Note: Fast foods and commercial snacks are usually high in sodium and have been linked with weak bones.

Dairy Products and Calcium-Rich Foods. Although some studies have reported that dairy products benefit the bones, it is not entirely clear if high-calcium diets reduce the risk for fractures compared to adequate intake of vitamin D. Until more is known, people should be sure their diets have sufficient calcium. Dietary calcium is available from many good sources.

Milk and Dairy Products. The best source of calcium in the diet is from milk fortified with vitamin D. Four glasses of milk provide about 1,200 mg of calcium. (Skim milk and yogurt products, unfortunately, are often low in vitamin D, which is important for calcium absorption.) According to a 2003 study, girls who have low milk intake increase their risk for fracture in adulthood. One report even suggests that milk proteins actually slow bone break down. It is not clear, however, if drinking milk after menopause offers any significant bone protection.
Other Calcium-Rich Foods. Other calcium-rich foods include shrimp, canned salmon or sardines, black strap molasses, calcium-fortified tofu, and almonds. A number of commercial foods, including orange juice and some cereals, are now calcium fortified. Dark green vegetables (broccoli, kale, turnip greens) are rich in calcium but little of it is absorbed (kale is best).

Click the icon to see an image of milk and the facial bones.

Mineral-Rich Fruits and Vegetables.

Potassium. Potassium may be very important for strong bones and may help counteract negative effects of high-protein diets. Potassium-rich fruits include bananas, oranges, prunes, and cantaloupes, and vegetables that contain potassium include carrots, spinach, celery, alfalfa, mushrooms, lima beans, potatoes, avocados, and broccoli.
Magnesium. Some studies have observed that low levels of magnesium may contribute to thinning bones. Some studies suggest that magnesium supplements help suppress the cycle that leads to bone loss. Experts recommend 350 mg a day for supplements. However, excessive magnesium may be harmful in people with diabetes or kidney disease. Foods rich in magnesium include dairy products, spinach, potatoes, beets, nuts, sole, and halibut.
Other Minerals. Phosphorous, boron, and zinc have also been associated with bone protection.

Protein. Protein may be important for frail older people for improving muscle strength. Researchers, meanwhile, have associated both low and high protein intake with bone loss. Protein deficiencies appear to trigger hormonal changes that increase bone breakdown. On the other hand, high protein intake increases urinary calcium loss, which can impair bone density in people with low-calcium diets. High-protein diets, however, do not appear to cause bone loss if calcium intake is also high. The bottom line is to eat enough protein but to balance it with plenty of calcium-rich, and other mineral-rich, foods.

The protein source (meat, soy, or fish) may have some effect on bone density, although the effects are not clear. Studies are mixed on whether protein from meat has a positive or negative effect on bone loss. In any case, the best sources of protein for bone protection may be from oily fish or soy.

Choosing protein from fish (especially oily fish such as sardines, salmon, mackerel, fresh tuna, and herring) is a good option. Oily fish are high in vitamin D, which is bone protective. Such fish are also heart protective. Wild salmon has a much higher vitamin D content than farmed salmon. American brands of canned tuna, meanwhile, generally do not contain significant amounts of vitamin D.
Soy may have some modest protection against bone loss. Soy is high in estrogen-like plant chemicals called isoflavones, which may improve bone health in older women. In particular, the isoflavone genistein is being studied for its effects on bone health. A small 2007 study indicated that genistein supplements, when taken with vitamin D and calcium, may help improve bone density in postmenopausal women with thinning bones. (However, other studies indicate that soy has no effect on bone density in healthy premenopausal women.) Soy food products that also contain calcium, such as tofu, may be particularly beneficial. In such cases, 3 ounces of tofu supply 60% of daily calcium requirements.

Alcohol. Alcohol has different effects on bones depending on how much is consumed. One study found that women older than age 65 who drank one to two drinks (1 - 2 oz) of alcohol weekly had higher bone density than non-drinkers. Alcohol in moderate amounts may reduce parathyroid hormone and increase estrogen levels. Excessive drinking, however, has been associated with brittle bones.

Cola, Coffee, Tea and Caffeine. One study suggested that drinking tea regularly may help protect bones. Nevertheless, there has been some concern that caffeine consumption, particularly from coffee, may increase calcium levels in urine and reduce levels in the body. In one trial, consumption of lots of coffee (9 or more cups per day) was associated with an increased risk of hip fractures in women, but not in men. However, not all studies support a risk. Some evidence suggests that caffeine may pose a danger for bone loss only in elderly thin women -- but not in those who have normal or high weight. Drinking carbonated beverages, particularly cola, may increase the risk for bone fractures in people with low bone density.

Everyone who smokes should quit. The risk for osteoporosis from smoking appears to diminish after quitting.

An important component in reducing the risk for fractures is preventing falls. Risk factors for falling include:

Slow walking
Inability to walk in a straight line
Certain medications (such as tranquilizers and sleeping pills)
Low blood pressure when rising in the morning
Poor vision

Recommendations for preventing falls or fractures from falls in elderly people include:

Exercise to maintain strength and balance if there are no conflicting medical conditions. In one study of older people, this was the single best intervention for preventing falls.
Do not use loose rugs on the floors.
Move any obstructions to walking, such as loose cords or very low pieces of furniture, away from traveled areas.
Rooms should be well lit.
Have regular eye checkups.
Try wearing hip pads. Hip pads are specially designed to protect hipbones against falls and are worn under clothing. Evidence on their protection against fractures is weak, however, particularly since compliance is poor. Nevertheless, newer hip pads that are thinner and made with newer materials may be helpful and more appealing.
Wear thinner, hard-soled shoes. Studies indicate these shoes are just as comfortable as the popular resilient-soled footwear, but they may be difficult to find. Soft-soled high-resilient so-called athletic footwear may contribute to impaired balance and dangerous falls, in part, because these cushioned shoes offer less stability.

Medications

Many drugs are available to treat osteoporosis. Unfortunately, studies continue to report that doctors fail to evaluate and adequately treat both men and women for this condition, even after a fracture. According to one study of women over age 60, fewer than 2% were evaluated for osteoporosis or spinal fracture by their doctors. Among those who were diagnosed, only 36% received appropriate medication. Among adults who had sustained fractures, less than 5% of men and fewer than half of women were evaluated and treated according to recommended guidelines, indicated two other studies. In one of the studies, only 24% of women received treatment for osteoporosis after a fracture. In both studies, the older a woman was, the less likely she was to have adequate evaluation or treatment.

Drugs Used to Treat Osteoporosis. Two types of drugs are used to treat osteoporosis:

Antiresorptive Drugs. Antiresorptives include bisphosphonates, hormone replacement therapy, selective estrogen-receptor modulators (SERMs), and calcitonin. Bisphosphonates are the standard drugs used for osteoporosis. These drugs block resorption (preventing bone break down), which slows the rate of bone remodeling, but they cannot rebuild bone. Because resorption and reformation occur naturally as a continuous process, blocking resorption may eventually also reduce bone formation.
Anabolic, or Bone-Forming, Drugs. Drugs that rebuild bone are known as anabolics. The primary anabolic drug is low-dose parathyroid hormone (PTH), which is administered through injections. This medicine is proving to be very effective in restoring bone and preventing fractions. PTH is still relatively new, and long-term effects are still unknown. Fluoride is another bone-building drug, but it has limitations and is not commonly used.

Both types of drugs are effective in preventing bone loss and fractures, although they vary in their effectiveness and safety.

Bisphosphonates are antiresorptive drugs. They are the primary drugs for preventing and treating osteoporosis. They can help reduce the risk of both spinal and hip fractures, including among patients with prior bone breaks.

Studies indicate that these drugs are effective and safe for at least 10 years. Eventually, however, bone loss continues with bisphosphonates. This may be due to the fact that bone breakdown is one of two phases in a continuous process of rebuilding bone. Over time, just blocking resorption will interrupt this process and impair the second half of the process -- bone formation. Some researchers think that this problem may be overcome by building bone for a couple of years with parathyroid hormone (PTH), then following this treatment with bisphosphonates to prevent the breakdown of bone. (Administering the two drugs simultaneously is not effective because bisphosphonates interfere with the way PTH works.)

A 2006 study of the bisphosphonate alendronate (Fosamax), the most widely used osteoporosis drug, indicated that women at low risk for fracture may be able to stop using the drug after 5 years without increasing their fracture risk for another 5 years. However, the Journal of the American Medical Association study also suggested that it is safer for women at high risk for spine fractures to keep taking alendronate on a continuous basis.

Candidates. National Osteoporosis Foundation guidelines recommend that the following people should take or consider bisphosphonates:

Women with a below-normal bone density of 2.5 standard deviation or greater and no history of fractures
Women with below-normal bone density 1 standard deviation or more and a history of fractures

Brands. Bisphosphonates are available in different forms:

Oral bisphosphonates. These pills include alendronate (Fosamax), risedronate (Actonel), and ibandronate (Boniva). Alendronate and risedronate are taken once a week. In 2005, ibandronate was approved as the first once-monthly pill. Risedronate is also available in a pill that contains calcium. Risedronate and alendronate are approved for both men and women.
Injectable bisphosphonates. In 2007, zoledronic acid (Reclast) was approved as the first once-yearly injection treatment for osteoporosis. The injectable form of ibandronate (Boniva), approved in 2006, requires injections 4 times a year. Injectable bisphosphonates are an alternative for patients who may have difficulty swallowing pills or sitting upright after oral bisphosphonate treatment.

Side Effects. The most distressing side effects of bisphosphonates are gastrointestinal problems, particularly stomach cramps and heartburn. These symptoms are very common and occur in nearly half of all patients. Other side effects may include irritation of the esophagus (the tube that connects the mouth to the stomach) and ulcers in the esophagus or stomach. Some patients may experience muscle and joint pain. To avoid stomach problems, doctors recommend:

Take the pill on an empty stomach in the morning with 6 - 8 ounces of water (not juice or carbonated or mineral water).
After taking the pill, remain in an upright position. Do not eat or drink for at least 30 - 60 minutes. (Check your drug’s dosing instructions for exact time.)
If you develop chest pain, heartburn, or difficulty swallowing, stop taking the drug and see your doctor.

Osteonecrosis (bone death) of the jaw is a rare side effect that has occurred mainly in patients who received intravenous bisphosphonates for cancer treatment (not osteoporosis). Many of these patients had major dental procedures before developing osteonecrosis. However, this bone decay condition has also been reported in some patients who have taken bisphosphonates by mouth (mainly alendronate). Symptoms may include jaw pain or swelling, gum infections, and poor healing of the gums. Talk to your doctor or dentist if you experience any jaw or gum discomfort while taking a bisphosphonate drug.

Raloxifene (Evista) belongs to a class of drugs called selective estrogen-receptor modulators (SERMs). These drugs are similar, but not identical, to estrogen. Raloxifene provides the bone benefits of estrogen without increasing the risks for estrogen-related breast and uterine cancers. Raloxifene was approved in 1997 to prevent osteoporosis in postmenopausal women, and in 1999 for the treatment of osteoporosis in postmenopausal women. In 2007, the Food and Drug Administration approved raloxifene for prevention of breast cancer in postmenopausal women with osteoporosis, as well as postmenopausal women at high risk for invasive breast cancer.

While there are many SERM drugs, raloxifene is the only one approved for both treatment and prevention of osteoporosis. Only postmenopausal women who have or are at risk for osteoporosis should take this drug. Studies indicate that raloxifene can stop the thinning of bone and help build better quality and stronger bone.

A thrombus is a blood clot that forms in a vessel and remains there. An embolism is a clot that travels from the site where it formed to another location in the body. Thrombi or emboli can lodge in a blood vessel and block the flow of blood in that location, depriving tissues of normal blood flow and oxygen. This can result in damage, destruction (infarction), or even death of the tissues (necrosis) in that area.

Side Effects. Raloxifene increases the risk for blood clots in the veins. Because of this side effect, raloxifene also increases the risk for stroke (but not other types of heart disease). These side effects, though rare, are very serious. Women should not take this drug if they have a history of blood clots, or if they have certain risk factors for stroke and heart disease. More common mild side effects include hot flashes and leg cramps.

Produced by the thyroid gland, natural calcitonin regulates calcium levels by inhibiting the osteoclastic activity, the breakdown of bone. The drug version is derived from salmon and is available as a nasal spray (Miacalcin) and an injected form (Calcimar). Calcitonin is not used to prevent osteoporosis. It treats osteoporosis. It may be effective for spinal protection (but not hip) in both men and women. Calcitonin may be an alternative for patients who cannot take a bisphosphonate or SERM. It also appears to help relieve bone pain associated with established osteoporosis and fracture.

Side Effects. Side effects include headache, dizziness, anorexia, diarrhea, skin rashes, and edema (swelling). The most common adverse effect experienced with the injection is nausea, with or without vomiting. This occurs less often with the nasal spray. The nasal spray may cause nosebleeds, sinusitis, and inflammation of the membranes in the nose. Also, many people who take calcitonin develop resistance or allergic reactions after long-term use.

Although high persistent levels of parathyroid hormone (PTH) can cause osteoporosis, daily injections of low and intermittent doses of this hormone actually stimulate bone production and increase bone mineral density. In clinical studies, teriparatide (Forteo), a drug made from selected amino acids found in parathyroid hormone, reduced the risk for spinal and non-spinal fractures by 50 - 65%. It may prove to be a very useful drug for men with osteoporosis. Unlike most treatments for osteoporosis, including bisphosphonates, the benefits may persist even after the injections have been stopped.

Although the treatment requires injections, researchers are investigating a nasal spray version of PTH. In addition to easing patient discomfort, there is some preliminary evidence that nasal-administered PTH may be better absorbed than injections. Side effects of PTH are generally mild and include nausea, dizziness, and leg cramps. No significant complications have been reported to date.

Early animal studies did report bone tumors in mice that were given parathyroid long-term. Such effects have not been observed in humans to date. However, people with Paget disease, (a disorder in which bone thickens but also, oddly, weakens), should not take parathyroid hormone, since they are at higher than normal risk for bone tumors.

Hormone replacement therapy (HRT) is sometimes used to prevent osteoporosis. A Women’s Health Initiative (WHI) study found that women who received estrogen, or estrogen plus progestin, therapy had fewer fractures than women who received placebo.

However, WHI studies have also shown that estrogen increases the risk for breast cancer, blood clots, strokes, and heart attacks. For this reason, women need to balance the benefits that HRT has on bone-loss protection, with the risks it carries for other serious health conditions. The Food and Drug Administration recommends that women first try other medications for prevention of osteoporosis.

HRT is available in many different forms, including pills and skin patches. [See In-Depth Report #40: Menopause.]

New SERMs. Bazedoxifene (Viviant) is a new selective estrogen receptor modulator (SERM) that is in phase III clinical trials. In research presented at the 2007 annual meeting of the American Society for Bone and Mineral Research (ASBMR), bazedoxifene reduced new cases of non-spine fracture by 52% compared to placebo.
Biologic Drugs. Denosumab is a humanized monoclonal antibody injectable drug currently in phase III studies. It targets the RANK ligand, a protein involved with cells that break down bone (osteoclasts). Results presented at the 2007 ASBMR meeting indicated that denosumab may help increase bone mineral density by as much as 10.6%. Odanacatib is another biologic drug showing promise in phase IIB trials. Odanacatib inhibits cathepsin K, a protein that also plays a role in osteoclast activity.
Strontium. Strontium, a chemical element found in bone, may help increase bone formation and decrease bone resorption. NB S101 is a strontium drug currently in phase II trials.

Treatment

Nonsurgical treatments for fractures include braces, plaster cases, and manipulation of the fracture. Such approaches have not been well studied to determine an optimal method, and patients should discuss all options with their doctors.

Reconstructive surgery is usually used for hip fractures and should be performed within 48 hours, assuming the patient has no other complicating medical conditions. After surgery, the patient should be mobilized within the first day. In one study, protein supplements helped people with hip fractures recover more quickly and reduced bone loss.

Percutaneous vertebroplasty and kyphoplasty are surgical procedures used to lessen pain. Research to date suggests that they are safe and provide pain relief for many patients. In some cases they may increase height. There have been few controlled trials, however, and more research is needed to determine long-term effects.

Percutaneous Vertebroplasty. Percutaneous vertebroplasty involves the injection of a cement-like bone substitute into damaged vertebrae. It is proving useful for stabilizing the spine and relieving pain in patients with spinal compression fractures due to osteoporosis or cancer. Success rates of over 90% have been reported. Serious complications occur in fewer than 1% of cases.

Kyphoplasty. Kyphoplasty is a variant of percutaneous vertebroplasty that may help prevent kyphosis (hunchback) in patients whose spines have collapsed. The procedure inserts a balloon into the fractured vertebrae. As the balloon inflates, the spine is moved upward, to its original location. The balloon is then removed, and the bone and the core of the newly-erect vertebrae are filled with cement. In one 2003 study, short-term symptom relief improved by 70% and was immediate. Long-term effectiveness is not yet known.

Resources

www.nof.org -- National Osteoporosis Foundation
www.niams.nih.gov/Health_Info/Bone -- National Institutes of Health, Osteoporosis and Related Bone Diseases
www.menopause.org -- North American Menopause Society
www.asbmr.org -- American Society for Bone and Mineral Research
www.niams.nih.gov -- National Institute of Arthritis and Musculoskeletal and Skin Diseases

References

Agency for Healthcare Research and Quality. Effectiveness and Safety of Vitamin D in Relation to Bone Health, Structured Abstract. August 2007. Rockville, MD.

Bilezikian JP. Osteonecrosis of the jaw -- do bisphosphonates pose a risk? N Engl J Med. 2006 Nov 30;355(22):2278-81.

Black DM, Delmas PD, Eastell R, Reid IR, Boonen S, Cauley JA, et al. Once-yearly zoledronic acid for treatment of postmenopausal osteoporosis. N Engl J Med. 2007 May 3;356(18):1809-22.

Black DM, Schwartz AV, Ensrud KE, Cauley JA, Levis S, Quandt SA, et al. Effects of continuing or stopping alendronate after 5 years of treatment: the Fracture Intervention Trial Long-term Extension (FLEX): a randomized trial. JAMA. 2006 Dec 27;296(24):2927-38.

Diem SJ, Blackwell TL, Stone KL, Yaffe K, Haney EM, Bliziotes MM, et al. Use of antidepressants and rates of hip bone loss in older women: the study of osteoporotic fractures. Arch Intern Med. 2007 Jun 25;167(12):1240-5.

Haney EM, Chan BK, Diem SJ, Ensrud KE, Cauley JA, Barrett-Connor E, et al. Association of low bone mineral density with selective serotonin reuptake inhibitor use by older men. Arch Intern Med. 2007 Jun 25;167(12):1246-51.

Marini H, Minutoli L, Polito F, Bitto A, Altavilla D, Atteritano M, et al. Effects of the phytoestrogen genistein on bone metabolism in osteopenic postmenopausal women: a randomized trial. Ann Intern Med. 2007 Jun 19;146(12):839-47.

Tang BM, Eslick GD, Nowson C, Smith C, Bensoussan A. Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis. Lancet. 2007 Aug 25;370(9588):657-66.

Yang YX, Lewis JD, Epstein S, Metz DC. Long-term proton pump inhibitor therapy and risk of hip fracture. JAMA. 2006 Dec 27;296(24):2947-53.

Review Date:
11/1/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

adam.com

Sleep apnea

FitSugar — Wed, 08 Oct 2008 17:35:30 -0700

In This Report

Highlights
Introduction
Symptoms
Causes
Risk Factors
Prognosis
Diagnosis
Lifestyle Changes
Treatment
Dental Devices
Surgery
Resources
References

HEALTH GUIDE REFERENCE FROM A.D.A.M

Highlights

Sleep Apnea and Heart Attack

Obstructive sleep apnea can increase the risk of heart attack by as much as 30% over the course of 5 years, suggests a study presented at the 2007 American Thoracic Society International Conference. Researchers noted that the risk of developing or dying from heart disease rises with increasing sleep apnea severity.

Sleep Apnea and Diabetes

Obstructive sleep apnea may increase the risk of developing type 2 diabetes, indicates research presented at the American Thoracic Society conference. Patients who had severe obstructive sleep apnea had more than 2.5 times the risk of developing diabetes as those who did not suffer from nighttime breathing problems.
Sleep apnea may also increase the risk for women developing diabetes during pregnancy (gestational diabetes). Pregnancy-associated high blood pressure is also linked with sleep apnea.

Sleep Apnea and Depression

As sleep apnea worsens, the odds for developing depression increase, indicates a 2006 study in the Archives of Internal Medicine.

Continuous Positive Airway Pressure (CPAP)

CPAP is the best treatment for severe sleep apnea. However, according to a 2007 study in Sleep, most patients need to use it for a full night’s duration to achieve optimal benefits. The researchers noted that many patients experience some improvement in daytime sleepiness after 4 - 6 nightly hours of CPAP use, but that the best improvements in quality of life occur mostly after 7.5 hours of CPAP use each night.

Risk Factors for Sleep Apnea Surgery

According to a 2006 study in the Archives of Otolaryngology - Head & Neck Surgery, the risks for complications following uvulopalatopharyngoplasty (UPPP) increase with:

Severity of sleep apnea
Being overweight (higher body mass index)
Having other medical conditions in addition to sleep apnea
Undergoing other surgical procedures at the same time as UPPP

Introduction

Sleep apnea is a disorder in which a person stops breathing during the night, perhaps hundreds of times, usually for periods of 10 seconds or longer and sometimes for as long as a minute. These gaps in breathing are called apneas. The word apnea means absence of breath.

Sleep apnea is usually accompanied by snoring. People might not even know they have the condition. It inevitably causes daytime sleepiness.

Sleep apnea is grouped into three categories:

Obstructive
Central
Mixed

There is also another, less severe form of obstructed breathing, called upper airway resistance syndrome (UARS).

Obstructive sleep apnea (OSA) is the most common form of apnea. It occurs when tissues in the upper throat collapse at different times during sleep, thereby blocking the passage of air. In general, OSA occurs as follows:

On its way to the lungs, air passes through the nose, mouth, and throat (the upper airway).
Under normal conditions, the back of the throat is soft and tends to collapse inward as a person breathes.
Dilator (widening) muscles work against this collapse to keep the airway open. Interference or abnormalities in this process cause air turbulence.
If the tissues at the back of the throat collapse and become momentarily blocked, apnea occurs. Breath is temporarily stopped. In most cases the person is unaware of it, although sometimes they awaken and gasp for breath.
In some cases, the interference is incomplete (called obstructive hypopnea) and causes continuous but slow and shallow breathing. In response, the throat vibrates and makes the sound of snoring. Snoring can occur whether a person breathes through the mouth or the nose. (Snoring also occurs without sleep apnea.)
Apnea decreases the amount of oxygen in the blood, and eventually this lack of oxygen triggers the lungs to suck in air.
At this point, the patient may make a gasping or snorting sound but does not usually fully wake up.

Obstructive sleep apnea is defined as five or more episodes of apnea or hypopnea per hour of sleep in individuals who have excessive daytime sleepiness.

Central sleep apnea is much less common. It is caused by some problem in the central nervous system, most likely a failure of the brain to signal the airway muscles to breathe. In such cases, oxygen levels drop abruptly and usually the sleeper wakes with a start. Often people with central sleep apnea recall waking up. They generally experience less sleepiness during the day than people with obstructive sleep apnea. Heart disease, and in particular heart failure, is the most common cause of central sleep apnea.

Mixed apnea is the term used when the two apneas occur together.

Upper airway resistance syndrome (UARS) is a condition in which patients snore, wake frequently during the night, and have excessive daytime sleepiness. However, UARS patients do not have the breathing abnormalities that characterize sleep apnea and they do not show a reduction in blood oxygen levels. Unlike apnea, UARS is more likely to occur in women than in men. Treatments are similar to those of sleep apnea. It is not known if UARS has any serious health complications.

In sleep studies, subjects spend about one-third of their time asleep, suggesting that most people need about 8 hours of sleep each day. Individual adults differ in the amount of sleep they need to feel well rested, however. Infants may sleep up to 16 hours a day.

The daily cycle of sleeping and waking is called the circadian rhythm. It's commonly referred to as the biologic clock. Circadian means "about a day." Hundreds of bodily functions follow biologic clocks, but sleeping and waking comprise the most prominent circadian rhythm. The sleeping and waking cycle is approximately 24 hours. (People who are confined to windowless homes, with no clocks or other time cues, sleep and wake on a slightly longer cycle.) The 24-hour circadian rhythm typically adheres to the following factors:

Humans are designed for daytime activity and nighttime rest.
There is a natural peak in sleepiness at mid-day, the traditional siesta time.

In addition, daily rhythms mix with other factors that may interfere or change individual patterns:

The firing of nerve cells in the brain may be faster or slower in different individuals.
The monthly menstrual cycle in women can shift the pattern.
Light signals coming through the eyes reset the circadian cycles each day, so changes in season or various exposures to light and dark can unsettle the pattern. The importance of sunlight as a cue for circadian rhythms is dramatized by the problems experienced by people who are totally blind. They commonly suffer trouble sleeping and other rhythm disruptions.

The Response in the Brain to Light Signals

The response to light signals in the brain is an important key factor in sleep:

Light signals travel to a tiny cluster of nerves in the hypothalamus in the center of the brain, the body's master clock, which is called the supra chiasmatic nucleus or SCN.
This nerve cluster takes its name from its location. It sits just above (supra) the optic chiasm, a major junction for nerves transmitting information about light from the eyes.
The approach of dusk each day prompts the SCN to signal the nearby pineal gland to produce the hormone melatonin.
Melatonin is thought to act as the body's time-setting hormone. The longer a person is in darkness the longer the duration of melatonin secretion. Secretion can be diminished by staying in bright light. Melatonin also appears to trigger the need to sleep.

Sleep Cycles

Sleep consists of two distinct states that alternate in cycles and reflect differing levels of brain nerve cell activity:

Non-Rapid Eye Movement Sleep (NonREM). NonREM sleep is also termed quiet sleep. NonREM is further subdivided into three stages of progression:

Stage 1 (light sleep)
Stage 2 (so-called true sleep)
Stage 3 to 4 (deep "slow-wave" or delta sleep)

With each descending stage, awakening becomes more difficult. It is not known what governs NonREM sleep in the brain. A balance between certain hormones, particularly growth and stress hormones, may be important for deep sleep.

Rapid Eye-Movement Sleep (REM). REM sleep is termed active sleep. Most vivid dreams occur in REM sleep. REM-sleep brain activity is comparable to that in waking, but the muscles are virtually paralyzed, possibly preventing people from acting out their dreams. In fact, except for vital organs like lungs and heart, the only muscles not paralyzed during REM are the eye muscles. REM sleep may be critical for learning and for day-to-day mood regulation. When people are sleep-deprived, their brains must work harder than when they are well rested.

The REM/NREM Cycle. The cycle between quiet (NonREM) and active (REM) sleep generally follows this pattern:

After about 90 minutes of NonREM sleep, eyes move rapidly behind closed lids, giving rise to REM sleep.
As sleep progresses the NonREM/REM cycle repeats.
With each cycle, NonREM sleep becomes progressively lighter, and REM sleep becomes progressively longer, lasting from a few minutes early in sleep to perhaps an hour at the end of the sleep episode.

Symptoms

People with sleep apnea usually do not remember waking during the night.

Symptoms may include:

Excessive daytime sleepiness
Morning headaches
Irritability and impaired mental or emotional functioning
Snoring (bed partners may report very loud and interrupted snoring)
Heartburn (acid back-up that causes heartburn may be responsible for some cases of sleep apnea)

Sleep apnea occurs in about 2% of children. They may have symptoms that differ from adults, including:

Longer total sleep time than normal in some children, especially obese children or those with severe apnea.
Snoring. (An estimated 3 - 12% of all children snore. However, not all of them have sleep apnea.)
More effort in breathing (flaring nostrils, heaving chests, sweating). The chest may have an inward motion during sleep.
Behavioral difficulties without any obvious cause, such as hyperactivity and inattention. (Some patients may even be misdiagnosed with attention-deficit hyperactivity disorder.)
Irritability
Bed-wetting
Morning headaches
Failure to grow and gain weight

Causes

Any structural abnormality in the face, skull, or airways that causes some obstruction or collapse in the upper airways and reduces air pressure can produce sleep apnea syndrome. Abnormalities in tissues that lie between the back of the mouth and the esophagus (food pipe) are one of the most common structural causes of sleep apnea. Enlarged soft palates (the base of the tongue and surrounding throat walls) are also associated with many cases of sleep apnea.

Researchers have identified several physiologic abnormalities that may play a role in causing sleep apnea or in making it worse. These include an inability to regulate levels of carbon dioxide, impaired brain and nervous system responsiveness to various chemical messengers, and poor reflexes or muscle tone in the upper airways. The underlying reasons for these disturbances and their connection to apnea require further study.

Obesity is strongly associated with sleep apnea and is a cause of it in some cases. Imaging scans have shown fatty cells clogging the throat tissue, which indicates that they narrow the airways. In one study, the more obese a person with sleep apnea was, the higher the pressure on the airway and therefore the greater the obstruction of the airway. (Obstructive sleep apnea may also contribute to obesity itself, however, since a sleepy person tends to be sedentary.)

Snoring. Chronic snoring itself may actually be a cause of sleep apnea. Over time, the vibrations and the increased pressure against the upper airways as snoring people inhale may cause the soft palate to lengthen. This stretched palate is more prone to collapse and obstruction.

It should be stressed that snoring is very common. Snoring occurs in about a third of the population, while apnea, according to one study, occurs in only 6%. Snoring, then, does not always cause apnea, nor is it always a sign of the respiratory disorder. Furthermore, while snoring is also associated with daytime sleepiness regardless of whether apneas are present, snoring alone does not appear to pose any major health risks.

Mouth Breathing. Some evidence suggests that a tendency to breathe through the mouth (rather than the nose) during childhood can actually produce structural changes in the face (longer face, narrow jaw, receding chin). Such facial characteristics may eventually put people at risk for sleep apnea.

Sleep apnea occurs in about 2% of children and can occur even in very young children. The most likely causes are the following:

Facial or skull abnormalities in infants.
Overgrown tonsils, adenoids, or both in small children. (Removal of tonsils or adenoids can free the airways and solve the problem.)
Premature infants also commonly have a form of apnea that may be related to lung or nervous system problems.

Risk Factors

Gender. More men than women appear to have sleep apnea. In the U.S., about 4% of men and 2% of women age 30 - 60 meet the criteria for obstructive sleep apnea. Such people have at lease five episodes of apnea or hypopnea (shallow nighttime breathing) for each hour of sleep plus excessive daytime sleepiness. A much higher percentage has just one of these two conditions.

Sleep apnea actually may be underdiagnosed in women, particularly older women. In general, older women have the same incidence of sleep apnea as men their own age. It is not clear why apnea occurs more often in men than women before menopause and why prevalence equalizes after menopause. Men tend to have larger necks and to weigh more than women and women tend to gain weight and develop larger necks after menopause. However, studies have not found that these physical factors fully explain the differences in risk by gender in young adults or the increase in sleep apnea in postmenopausal women.

Age. Sleep apnea is most common and its symptoms are worse in middle-aged adults age 40 - 60 years old. Nevertheless, it affects people of all ages.

Ethnicity. African-Americans face a higher risk for sleep apnea than any other ethnic group in the United States. Other groups at increased risk include Pacific Islanders and Mexicans.

Obesity, especially having fat around the abdomen (the so-called apple shape), is a particular risk factor for sleep apnea, even in adolescents and children. However, many people with sleep-related breathing disorders, particularly women and small children, are not obese. Also, not all people who are obese have sleep apnea. Specific anatomical and physiological properties in the airways are more likely to be present in obese individuals with apnea.

Having a Larger Neck. Having a large neck is a risk factor for sleep apnea. In fact, larger necks in men may be the primary reason for their higher risk for sleep apnea compared to women. A neck measurement of 17 inches or greater in men or at least 16 inches in women is one indicator that may suggest the condition. Postmenopausal women are more likely than younger women to have sleep apnea, in part because they tend to be heavier and have larger necks.

Specific Facial and Skull Characteristics. Structural abnormalities in the face and skull may be responsible for many cases of sleep apnea. These are likely to be the cause in many non-obese people with early-onset sleep apnea, particularly if they also have a family history of the problem.

Specific physical characteristics that may increase the risk for sleep apnea in both adults and children include:

A long lower part of the face
Brachycephaly, a birth defect in which the head tends to be shorter and wider than average
A narrow upper jaw
A receding chin
An overbite
A larger tongue

Characteristics in the Soft Palate. Some people have specific abnormalities in the soft area (palate) at the back of the mouth and throat that may lead to sleep apnea. These abnormalities include:

The soft palate is stiffer, larger than normal, or both. An enlarged soft palate may be a significant risk factor for sleep apnea.
The soft palate and the walls of the throat around it collapse easily.

Smoking. Smokers are at higher risk for apnea. Those who smoke more than two packs a day have a risk 40 times greater than nonsmokers.

Alcohol. Alcohol use has been associated with apnea, although studies are mixed. A major survey reported that 53% of people who use alcohol to help fall sleep experience symptoms of sleep apnea. Another study found no relationship.

Diabetes. Diabetes is associated with sleep apnea and snoring. It is not clear if there is an independent relationship between the two conditions or whether obesity is the only common factor.

Gastroesophageal Reflux Disease (GERD). GERD is a condition caused by acid backing up into the esophagus. It is a common cause of heartburn. GERD and sleep apnea often coincide. In one study, almost half of apnea patients had symptoms of GERD. Some experts suggest that the backup of stomach acid in GERD may produce spasms in the vocal cords (larynx), thereby blocking the flow of air to the lungs and causing apnea. Or, apnea itself may cause pressure changes that trigger GERD. Some evidence suggests that treating sleep apnea with continuous positive airway pressure (CPAP) may reduce GERD symptoms by nearly 50%. However, obesity is common in both conditions. More research is needed to clarify the association.

Polycystic Ovary Syndrome (PCOS). In a 2000 study, women with PCOS were 30 times more likely than other premenopausal women to have obstructive sleep apnea and excessive daytime sleepiness. Women with PCOS produce high amounts of male hormones, particularly testosterone, which can cause obesity, facial hair, and acne. About half of PCOS patients also have diabetes. Obesity and diabetes are both associated with sleep apnea and may be the common factors.

Chronic Problems in the Upper Airways. A 2001 Swedish study found that people with respiratory tract disorders, including asthma, chronic bronchitis, or seasonal allergies, reported symptoms of sleep apnea more often than those without any of these ailments.

Hypothyroidism. In rare cases, hypothyroidism (low thyroid) has been reported as a possible cause of sleep apnea. In such cases, treating the thyroid condition improves the sleep apnea.

Prognosis

Sleep apnea has a strong association with several diseases, particularly those related to the heart and circulation.

Researchers are intensively investigating why a problem in the upper airways is associated with serious conditions of the heart and circulatory system. Here are some of their findings:

Major known risk factors for hypertension and heart disease (obesity, smoking, and alcohol abuse) are associated with sleep apnea. These factors, however, do not explain all cases of higher heart-related risks in people with sleep apnea. For example, among overweight people, those who have sleep apneas have a greater risk of heart problems than those without them.
When breathing stops during episodes of apnea, carbon dioxide levels in the blood increase and oxygen levels drop. This effect may trigger a cascade of physical and chemical events that can then increase risk for heart problems.
Apnea also causes decreased levels of the gas nitric oxide (NO), a potent substance that causes blood vessels to be elastic and expand. NO plays a crucial role in blood pressure control and heart health.
Apnea may also increase levels of a substance called angiotensin-converting enzyme (ACE), which is known to play a role in high blood pressure and congestive heart failure.
Researchers have reported high levels of certain immune factors called tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6) in people with sleep apnea, particularly those who are obese. High levels of TNF-alpha and IL-6 produce a damaging inflammatory response, which can harm cells in the body, including those in the arteries. Elevated TNF-alpha may be associated with fatigue, shortness of breath, and a diminished heart-pumping action.

At this time, however, evidence of a clear causal relationship with any of these health problems is still weak. Some studies have found no significant independent risk for heart disease from obstructive sleep apnea. The following are some discussions on the possible effects of apnea on specific health problems.

High Blood Pressure. A number of studies have found a strong association between sleep apnea and high blood pressure (hypertension). (In the past, the link between sleep apnea and hypertension was thought to be due to obesity, a risk factor for both conditions, but more recent studies contradict that theory.) A 2000 study followed patients for 4 years; the more nightly apnea episodes they had in the first year, the more likely they were to develop hypertension by the fourth year. A weak, but still higher-than-normal, association with high blood pressure has also been observed in those who snore, wake frequently during the night, or have mild sleep apnea.

A 2004 data analysis of over 200,000 patient records revealed that people who took both antidepressants and antihypertensives were 18 times more likely to be diagnosed with obstructive sleep apnea than those who did not take the medications. The probability was highest among adults age 20 - 39 years. These drugs do not cause sleep apnea, but antidepressants may be prescribed to treat hypertensive patients’ complaints of fatigue even if sleep apnea is the real cause. The researchers recommended that patients being treated for high blood pressure, depression, and fatigue should also be evaluated for sleep apnea.

One way that apnea may directly affect blood pressure, regardless of other risk factors:

Blood pressure fluctuates widely and suddenly in response to episodes of apnea and hypopnea (shallow nighttime breathing).
Such fluctuations are possibly due to a sudden surge in the sympathetic nervous system, which controls involuntary muscle responses, importantly those in the blood vessels and heart, and may also play a role in sleep apnea.
These fluctuations lead to transient constriction of blood vessels that, over time, could possibly lead to sustained hypertension and heart damage.
Effective treatment of sleep apnea with continuous positive airway pressure (CPAP) may reduce blood pressure. Sleep apneas must be significantly reduced, however, to have any effect on blood pressure. Even a 50% reduction in apneas has no effect.

Coronary Artery Disease and Heart Attack. Sleep apnea has been associated with heart disease regardless of the presence of high blood pressure or other heart risk factors. In a 2001 study, researchers observed that the more episodes of apnea and hypopnea a patient had, the higher the risk for a heart attack.

Many of the factors associated with stroke and sleep apnea (a risk for blood clots and narrowing of the arteries) may also increase the risk for heart attacks. Research presented at the 2007 American Thoracic Society conference suggested that severe obstructive sleep apnea can increase the risk of dying from a heart attack by as much as 30% over a 4 - 5 year period. Obstructive sleep apnea, however, may have other effects that increase the risk for heart problems:

Some evidence suggests that obstructive apneas cause an increase in stiffness and inflammation in the arteries, which is now proving to be an important aspect of heart disease, particularly in older adults.
A 2002 study reported that the white blood cells of patients with apnea have an increased number of proteins called adhesion molecules on their surface that may bind to the lining of blood vessels and cause inflammation. Increasingly, scientists believe that inflammation plays an important role in the development of coronary artery disease, heart attacks, and many other major ailments.

Stroke. Sleep apnea doubles the risk for stroke. The worse the sleep apnea, the greater the risk; moderate-to-severe obstructive sleep apnea can triple the risk of stroke. Sleep apnea is also associated with high blood pressure, a known risk factor for stroke. However, people who have sleep apnea, but not high blood pressure, are also still at increased risk for stroke. Sleep apnea in stroke patients is also associated with a higher risk for worse symptoms after a stroke, including delirium, depression, poor response to speech, and difficulty conducting daily chores.

A 2000 study observed that blood becomes more viscous (stickier) in the morning in people with obstructive sleep apnea compared to people without the sleep disorder. Such "sticky" blood is more apt to form clots that can lead to strokes. To support this, another 2000 study reported that stroke victims with sleep apnea tended to have higher levels of the blood protein fibrinogen than stroke victims without sleep apnea. Fibrinogen is a factor in blood that causes it to clot. Higher levels of fibrinogen have been linked to both strokes and heart attacks.
A 1998 study reported that the carotid artery, the major artery to the brain, is in far greater danger of becoming sclerotic (hardened and narrower) in people with obstructive sleep apnea than in the average person. People with both diabetes and sleep apnea are at particularly high risk for this effect.

Heart Failure. Studies suggest that 11 - 37% of patients with heart failure also have sleep apnea. Both central and obstructive sleep apnea are linked with heart failure. The evidence for the association between heart failure and sleep apnea includes:

High blood pressure, which is associated with sleep apnea, is a major cause of later heart failure.
Sleep apnea reduces oxygen levels and causes abnormal changes in blood pressure and heart rate that add to the burden of the failing heart.
Obstructive sleep apnea can affect breathing functions that are particularly harmful for patients with existing congestive heart failure.
Sleep apnea is associated with poorer survival in patients with heart failure. Some studies have suggested that treating sleep apnea with CPAP may improve heart function in these patients. However, a 2005 New England Journal of Medicine study found that CPAP did not improve survival in patients with heart failure and central sleep apnea

Atrial Fibrillation. Sleep apnea is more common in people with atrial fibrillation (irregular heartbeat) than in patients with other heart conditions. In a 2005 study published in Circulation, 49% of patients with atrial fibrillation were at risk for developing apnea, compared with 32% of general cardiology patients. An earlier study indicated that patients with untreated obstructive sleep apnea may be at increased risk for recurrence of atrial fibrillation. Patients with atrial fibrillation who received CPAP treatment had a lower risk for recurrence.

Metabolic Syndrome. The metabolic syndrome (also called Syndrome X) is a cluster of abnormalities that cause insulin resistance. Some of these factors, including hypertension and obesity, are also associated with sleep apnea. A 2004 study found that metabolic syndrome was nine times more common among patients with obstructive sleep apnea, independent of obesity.

Diabetes. Severe obstructive sleep apnea may more than double the risk of developing type 2 diabetes. Sleep apnea also increases the risk for diabetes during pregnancy (gestational diabetes).

When it comes to sleep apnea and obesity, it is not always clear which condition is responsible for the other. For example, obesity is often a risk factor and possibly a cause of sleep apnea, but it is also likely that sleep apnea increases the risk for weight gain. Some studies indicate that sleep apnea disrupts rapid eye movement (REM) sleep, which, in turn, increases the risk for obesity. Research indicates that animals deprived of REM sleep tend to eat more. People with apnea may also become too tired to exercise and so put on weight.

Sleep apnea is associated with a higher incidence of many medical conditions, other than heart and circulation. The links between apneas and the conditions are unclear.

Pulmonary hypertension.
Asthma. Sleep apnea may worsen asthma symptoms and interfere with the effectiveness of asthma medications. Treating the apnea may help asthma control.
Kidney failure.
Peripheral nerve damage (tingling, pain, or numbness in the hands and feet).
Liver damage in obese individuals with sleep apnea. Recent research suggests that severe apnea may increase the risk of liver disease regardless of weight.
Seizures, epilepsy, and other nerve disorders. Sleep apnea appears to pose a particularly risk for nocturnal epilepsy, a condition in which seizures occur during sleep.
Headaches. Sleep disorders, including apnea, may be the underlying causes of some chronic headaches. In some patients with both chronic headaches and apnea, treating the sleep disorder has cured the headache, even the very severe and disabling form known as a cluster headache.
High-risk pregnancies. Sleep apnea causes higher rates of pregnancy complications, including gestational diabetes and high blood pressure.
Eye disorders, including glaucoma, conjunctivitis, dry eye, and various other infections and irritations. Findings presented at the 2003 annual meeting of the American Academy of Ophthalmology suggested that patients with sleep apnea may be at increased risk for glaucoma and should be tested for this eye disease. A vision-damaging condition called intracranial hypertension has also been observed in some patients with sleep apnea.

Studies report an association between severe apnea and psychological problems. In one study, 32% of patients had symptoms of depression. According to a 2006 study, the risk for depression rises with increasing severity of sleep apnea. Sleep-related breathing disorders can also worsen nightmares and post-traumatic stress disorder. Certainly, daytime sleepiness interferes with mental alertness and quality of life.

Because sleep apnea so often includes noisy snoring, the condition can also adversely affect the sleep quality of a patient's bed partner. Spouses or partners may also suffer from sleeplessness and fatigue. In some cases, the snoring can disrupt relationships. Diagnosis and treatment of sleep apnea in the patient can help eliminate these problems.

Failure to Thrive. Small children with undiagnosed sleep apnea may "fail to thrive," that is, they do not gain weight or grow at a normal rate and they have low levels of growth hormone. In severe cases, this may affect the heart and central nervous system. Most often, sleep apnea in children is caused by overgrown tonsils or adenoid. Their removal often completely solves all of these problems, including resolution of sleep apnea and restoring weight gain and normal growth hormone levels.

Attention Deficits and Hyperactivity. Problems in attention and hyperactivity are common in children with sleep apnea. There is some evidence that such children may be misdiagnosed with attention-deficit hyperactivity disorder. Snoring, rather than sleepiness, is a stronger risk factor for hyperactivity in many of these children, especially boys under 8 years old. (Even children who snore and do not have sleep apnea may be at higher risk for poor concentration.)

Some researchers believe that sleepiness associated with sleep apnea is the greatest risk factor for car accidents. As many as 200,000 automobile accidents in the U.S. and 1,500 deaths from such accidents are caused by sleepiness. Studies continue to report that drowsy driving is as risky as drunk driving. Several studies have suggested that people with sleep apnea have two to three times as many car accidents, and five to seven times the risk for multiple accidents.

Diagnosis

Not all people with suspected sleep apnea require medical tests. Expensive diagnostic efforts are probably not required for individuals who have no other health risk factors and whose suspected apnea does not affect their quality of life or safety on the road.

Doctors, however, should order diagnostic sleep studies if:

The patient has a serious medical condition that might be worsened or caused by sleep apnea. Such conditions include heart disease, high blood pressure, heart failure, diabetes, chronic headaches, epilepsy, obstructive lung disease, or severe acid reflux (GERD).
A child who shows signs of sleep apnea also has attention deficit problems or fails to thrive.
The sleep apnea is severe enough to impair quality of life, increase the risk for accidents, or both.

In some cases of an uncertain diagnosis, high-risk patients may need to consult a sleep specialist or go to a sleep disorders center. At most centers, patients undergo an in-depth analysis, usually supervised by a multi-disciplinary team of consultants who can provide both physical and psychiatric evaluations. Centers should be accredited by the American Academy of Sleep Medicine.

To help determine the presence of sleep apnea, the doctor will ask the following questions:

Is the patient taking any medications?
How many periods of sleepiness are there each day and when do they occur? (Patients with apnea often do not describe this symptom as feeling "sleepy." They are more apt to describe this feeling as "lack of energy" or "feeling tired all day.")
How restful is sleep?
Do headaches occur regularly in the morning?
Is the patient taking or withdrawing from stimulants, such as coffee or tobacco?
How much alcohol is consumed per day?
Does the patient have any problems with mental or emotional functioning?
Does the patient suffer from heartburn?
What is the normal sleeping position (back, side, or stomach)?
If there is a sleeping partner, does he or she complain about the patient's snoring or gasping for breath? (Many times it is useful to interview the bed partner.)

Keeping a Record of Sleep. To help answer these questions, the patient may need to keep a sleep diary. Every day for 2 weeks, the patient should record all sleep-related information, including responses to questions listed above described on a daily basis. Recording sleep behavior using an extended-play audio or videotape can be very helpful in diagnosing sleep apnea.

To diagnose sleep apnea, the doctor will check for physical indications of sleep apnea, including:

Abnormalities in the soft palate or upper airways, including enlarged tonsils
Upper body obesity
A wide neck measurement

Some evidence suggests that doctors may accurately identify nearly all cases of suspected sleep apnea using physical criteria, including taking measurements of body mass (the indication of obesity), neck circumference, and four areas inside the mouth.

If sleep apnea is not obvious after a physical examination and history, the doctor will need to rule out any other problems. These include sleep disorders, (such as narcolepsy, insomnia, or restless legs disorder), or any medical or psychologic conditions (chronic fatigue syndrome, depression) that may be causing daytime sleepiness.

Polysomnography is the technical term for an overnight sleep study that involves recording brain waves and other sleep-related activity. Polysomnography involves many measurements and is typically performed at a sleep center.

The patient arrives about 2 hours before bedtime without having made any changes in daily habits. Polysomnography electronically monitors the patient as he or she passes, or fails to pass, through the various sleep stages. Polysomnography tracks:

Brain waves
Body movements
Breathing
Heart rate
Eye movements

Changes in breathing and blood oxygen levels are also recorded. In patients with suspected sleep apnea, the sleep expert will track instances of apnea and hypopnea that last longer than 10 seconds. In general, if there are more than five episodes per hour, apnea is significant and if there are more than 15, the condition is serious.

Overnight polysomnography has been the gold standard for diagnosing obstructive sleep apnea in both adults and children. It is very labor-intensive and expensive, however, and also misses snoring-induced arousals. It is not always covered by health insurance, and some centers have waiting lists that are months long.

A number of portable devices are available, or are being developed, so that patients have the convenience of being monitored at home. Experts hope that such monitors eventually will replace the need for overnight sleep clinics or the need for attended monitoring at home. Limited evidence exists, however, on the accuracy of many portable monitors. Patients with serious medical conditions, including heart failure or a history of stroke or respiratory failure, should not use home tests.

The following are descriptions of some home monitoring techniques.

Home Oximetry. Pulse oximetry is a procedure that determines if oxygen levels in the blood are low. This is called hypoxia. Normal levels during the night would generally rule out sleep apnea. With this procedure, a device called a pulse oximeter is attached to the patient's finger. The oximeter transmits red and infrared light through the capillaries in the finger. Hemoglobin, a molecule in the blood that carries oxygen, absorbs part of these light waves. The ratio of the two light beams provides the measurement of oxygen. The test is not always accurate, however. A combination with polysomnography, especially heart rate measurements, may be best for diagnosing sleep apnea.

Home oximetry monitors are available to rule out sleep apnea, but their accuracy is unclear. A 2003 study indicated that home oximetry alone was not very helpful in discriminating between patients with or without sleep apnea. Home oximetry however, may be helpful in identifying patients with unsuspected and seriously low oxygen levels.

Unattended Monitoring with Auto-CPAP. This method is a recent and simple method for detecting impaired breathing. It uses an auto-CPAP machine, which is programmed to apply pressure through the airways via a tube that attaches to a mask that fits the nose. A monitor is attached that digitizes and records on a computer all the information on any apnea episodes during sleep.

Nasal Pressure Recording. One promising technique uses a very simple prong device that attaches to the nostrils. A monitor records the airflow through the mouth and nose.

Peripheral Arterial Tonometry. An investigative technique called peripheral arterial tonometry measures changes in blood flow in the arteries of the fingertips during sleep. Such measurements are proving to be accurate in detecting sleep apnea in 80% of cases.

The Epworth Sleepiness Scale uses a simple questionnaire to measure excessive sleepiness during eight situations.


Situation	Chance of Dozing 0 = no chance of dozing 1 = slight chance of dozing 2 = moderate chance of dozing 3 = high chance of dozing
Sitting and reading.	(Indicate a score of 0 to 3)
Watching TV.	(Indicate a score of 0 to 3)
Sitting inactive in a public place (a theater or a meeting).	(Indicate a score of 0 to 3)
As a passenger in a car for an hour without a break.	(Indicate a score of 0 to 3)
Lying down to rest in the afternoon when circumstances permit.	(Indicate a score of 0 to 3)
Sitting and talking to someone.	(Indicate a score of 0 to 3)
Sitting quietly after a lunch without alcohol.	(Indicate a score of 0 to 3)
In a car, while stopped for a few minutes in traffic.	(Indicate a score of 0 to 3)
Score Results	1-6: Getting enough sleep 4-8: Tends to be sleepy but is average. 9-15: Very sleepy and should seek medical advice. Over 16: Dangerously sleepy

Lifestyle Changes

Sleeping on the back causes sleep apnea in about half of all people with mild sleep apnea. Body position greatly affects the number and severity of episodes of obstructive sleep apnea, with at least twice as many apneas occurring in people who lay on their back as in those who sleep on their side. This may be due to the effects of gravity, which cause the throat to narrow when a person lies on the back. (Indeed, astronauts show a marked reduction in apneas and snoring in the weightlessness of space.) Positional sleep apnea affects people of all ages, including young children.

As a first step in dealing with sleep apnea, the patient should simply try rolling over onto the side. Patients who sleep on their backs and have 50 - 80 apneas per hour can sometimes nearly eliminate them when they shift to one side or the other. (Changing positions is less effective the more overweight a person is, but it still helps.)

Here are some suggestions that might help a person maintain a low-risk sleeping position:

Sew a small pocket to the back of the pajamas and place a tennis ball or other small ball into it.
A special pillow that helps to stretch the neck may reduce snoring and improve sleep for people with mild sleep apnea.
Sleeping in an upright position may improve oxygen levels in overweight people with sleep apnea. Elevating the head of the bed may help.

Over-the-counter nasal strips, such as the Breathe Right strip or other devices that open the nostrils, are inexpensive and useful to prevent snoring. They may significantly improve early-stage sleep in people with sleep disorders associated with nasal obstruction and help reduce morning tiredness. They are not intended as treatments for sleep apnea, however.

All patients with obstructive sleep apnea who are overweight should attempt a weight-reducing program. Weight loss certainly reduces snoring in many people, sometimes stopping it completely. It also improves sleep and significantly reduces daytime sleepiness. A 2000 study suggested that people who lost 10% of body weight experienced an average 26% reduction in risk for developing sleep apnea in the first place. (Gaining 10% of their body weight, on the other hand, increased the odds of sleep apnea 6-fold.)

Smokers should quit, since smoking worsens apnea
Alcohol should be avoided within 4 hours of sleep

Treatment

Treatment for sleep apnea depends on the severity of the problem. Given the data on the long-term complications of sleep apnea, it is important for patients to treat the problem as they would any chronic disease. Simply trying to treat snoring will not treat sleep apnea. Because of its association with heart problems and stroke, sleep apnea that does not respond to lifestyle measures should be treated by a doctor, ideally a sleep disorders specialist.

At this time, the most effective treatments for sleep apnea are devices that deliver slightly pressurized air to keep the throat open during the night. There are a number of such devices available.

The best treatment for severe obstructive and mixed sleep apnea is a system known as continuous positive airflow pressure (CPAP), sometimes referred to as nasal continuous positive airflow pressure (nCPAP). It is safe and effective in sleep apnea patients of all ages, including children. CPAP is not recommended for patients with mild apnea. Patients with apnea but no daytime sleepiness report little or no benefit from this treatment.

CPAP works in the following way:

The device itself is a machine weighing about 5 pounds that fits on a bedside table.
A mask containing a tube connects to the device and fits over just the nose.
The machine supplies a steady stream of air through a tube and applies sufficient air pressure to prevent the tissues from collapsing during sleep.

Effects on Sleep and Wakefulness. A major 2003 analysis confirmed the benefits of CPAP on both objective and subjective measures of sleep. After using CPAP regularly many patients report the following benefits:

Restoration of normal sleep patterns.
Greater alertness and less daytime sleepiness.
Less anxiety and depression and better mood.
Improvements in work productivity.
Better concentration and memory. Some adults with symptoms of attention deficit hyperactivity disorder have improved after CPAP treatments for apnea. In two studies, however, equal improvements were also observed in people on sham CPAP, suggesting that the actual cognitive benefits from CPAP may be modest.
Patients' bed partners also report improvement in their own sleep when their mates use CPAP, even though objective sleep tests showed no real difference in the partners' sleep quality.

If patients do not experience less sleepiness after a period of time and are still complying with the regimen, then the airflow pressure may not be high enough. Patients may require retesting. Many patients report feeling more alert after CPAP treatments even if objective laboratory tests fail to show significant differences in the number of apneas and wake-up periods.

Protection from Accidents. Studies suggest that treatment with CPAP can reduce the risk for accidents. In a 2001 study, untreated patients had a risk for automobile accidents that was three times the risk in the general population. When these patients were treated, their risk fell to normal.

Effects on the Heart and Circulation. Evidence is mixed on whether CPAP treatment may reduce serious heart conditions. Early studies suggested that CPAP could improve heart function, lower blood pressure, and prevent new cardiac events (such as heart attacks) in patients with congestive heart failure and coronary artery disease. However, a 2005 study in the New England Journal of Medicine found that, while CPAP helped improve some heart disease symptoms, it did not affect overall survival in patients with heart failure and central sleep apnea. (Patients with heart failure often have central sleep apnea.)

It is also unclear whether CPAP improves blood pressure. A 2006 study of patients with high blood pressure and sleep apnea indicated that short-term (4 weeks) CPAP treatment has no significant effect on lowering blood pressure. (It is possible that longer-term treatment may be helpful.) Other studies have found blood pressure benefits from short-term CPAP treatment. Treatment for sleep apneas must be very effective, however, to have any benefits on blood pressure. Even a 50% reduction in apneas has no effect.

Effects on Other Medical Conditions. Some studies suggest other benefits with the use of CPAP:

Fewer morning headaches
Reduction in abdominal fat (abdominal fat has been related to a higher risk for diabetes and heart disease)
Lower blood sugar levels in patients with type 2 diabetes
Improved thinking and concentration in people with impaired mental function from sleep apnea
Modest lung improvement in patients with both apnea and chronic obstructive lung disease (such as emphysema)

CPAP works well for both adults and children, but many patients have problems getting used to the device. Unfortunately, CPAP devices are often cumbersome, which can lead to patients becoming discouraged and stopping treatment. All patients should be warned that the first few nights of CPAP therapy are unnerving. The device often produces anxiety, primarily because of the mask. Starting out with low pressure to get used to the mask may help. Patients may actually experience less sleep or sleep of a different quality in the beginning of treatment.

Nearly all patients complain about at least one side effect. Nearly half of complaints are related to the mask. Many of these problems can be reduced with a well-chosen mask that is comfortable and reduces leakage as much as possible. Common complaints include:

Irritation in the nose and throat. The most common complaints are nasal congestion and sore or dry mouth, which are caused by leakage that dries the airway. (This may be severe in elderly people or patients who have had uvulopalatopharyngoplasty, a surgical treatment for sleep apnea. Such patients are more likely to stop using CPAP.) Chin straps, nasal salt water sprays, or humidifiers may prevent these side effects. Heated humidification devices are also now available for CPAP users.
Excessive application of pressure making exhalation difficult.
A feeling of claustrophobia is a major factor in noncompliance. This can be improved by a lightweight and transparent mask or with masks known as nasal pillows, which are used only around the nostrils.
Up to 30% of patients experience irritation and sores over the bridge of the nose. Getting a properly fitted and cushioned mask can help reduce this effect.
Eye irritation or conjunctivitis.
Upper respiratory infections. It is very important to keep the unit clean.
Patients may also experience temporary chest muscle discomfort, which is caused by an increase in lung volume.
Severe side effects are very rare but may include heart rhythm disorders (arrhythmias), severe nose bleeding, and air pockets in the skull.
In addition to initial difficulties with its use, the fixed CPAP needs to be periodically readjusted. Patients can be trained to adjust the CPAP at home, thereby avoiding trips to the sleep professional for machine adjustments and making the process more convenient.

Although studies have reported that long-term compliance with CPAP systems is low, with about one-third of patients giving up the treatment, recent information suggests that it is improving, probably due to better technologies and better education. Patient education and support groups, a dedicated nurse to ensure close follow-up of patients (particularly in the first 2 weeks of therapy), and ready access to doctors to make adjustments as needed have all been shown to greatly improve compliance. (However, sleeping pills do not appear to help patients adapt to the device.) Not surprisingly, patients whose symptoms are noticeably relieved by the procedure early on are more likely to continue the therapy.

Because many patients find CPAP uncomfortable and difficult, they tend not to use it for the duration of the entire night. A 2007 study indicated that while some patients’ daytime sleepiness may improve after 4 - 6 hours of CPAP use each night, maximum benefits in quality of life require at least 7.5 hours of nightly CPAP use. It appears that longer nightly duration of CPAP use is best for achieving normal daytime functioning.

Bilevel Positive Airway Pressure. Bilevel positive airway pressure (BPAP) systems may be particularly helpful for patients with coexisting lung disease and those with excessive levels of carbon dioxide. These devices have a sensing feature that helps determine and vary the appropriate pressure depending on whether a person is breathing in or out. Greater pressure is needed on inhalation and less on exhalation. These machines are more expensive than the CPAP and may not be covered by insurance.

Automatic Titrating (Auto)-CPAP Pressure Devices. Even more sophisticated systems, called auto-CPAP devices, are available. These devices automatically customize air pressure for the individual patient. They usually use one of three methods:

Overall pressure is kept low until a specific problem is detected. At that time the pressure is automatically increased rapidly.
Pressure is low when there are no problems but is raised gradually when they are detected.
Pressure is gradually raised and lowered in response to problems or their absence. In addition, the device can change depending on problems within single breaths.

Brands include AutoAdjust, Virtuoso, and AutoSet. These devices are more expensive than those that provide continuous airflow. A 2003 study indicated that they may improve compliance, particularly in patients who require high CPAP use. They may be especially helpful for patients who require varying levels of pressure due to other conditions, such as seasonal allergies. They may also be useful as home diagnostic tools for sleep apnea. Auto-CPAP devices are not recommended for all patients, particularly those with heart failure or serious lung disease.

In general, drugs have not been very beneficial except for specific situations. Medications that treat accompanying disorders associated with sleep apnea may be helpful. The following may be helpful for certain patients:

Modafinil (Provigil), which is also used to treat narcolepsy, was approved by the FDA in 2004 as the first drug to treat the sleepiness associated with obstructive sleep apnea. However, Provigil is meant to be used in combination with -- not as a substitute for -- standard apnea treatments such as CPAP. Sleep experts stress that patients who take Provigil should adhere to CPAP treatment as the drug treats only the symptom of sleepiness, not the underlying health risks associated with sleep apnea.
Thyroid hormone may help sleep apnea in those with low thyroid (hypothyroidism).
Theophylline, a drug commonly used for asthma management, has shown promise in treating central sleep apnea in patients with heart failure.
Omeprazole (Prilosec), a drug used for patients with severe heartburn, may help patients with both sleep apnea and gastroesophageal reflux disorder (GERD).

Note on Sedatives. Sedatives, narcotics, and anti-anxiety drugs can actually worsen the breathing disturbances and arousal conditions that occur with sleep apnea. These substances cause the soft tissues in the throat to sag and diminish the body's ability to inhale. Apnea sufferers should never use sleeping pills or tranquilizers. Apnea patients undergoing surgery should be sure that their surgeons, anesthesiologists, and other doctors are aware of their sleeping disorder in considering sedatives, anesthetics, and medications taken to relieve pain due to surgery.

Dental Devices

Oral appliances, also called dental appliances or devices, may be an option for patients who cannot tolerate CPAP. The American Academy of Sleep Medicine recommends dental devices for patients with mild-to-moderate obstructive sleep apnea who are not appropriate candidates for CPAP or who have not been helped by it. (CPAP should be used for patients with severe sleep apnea whenever possible.)

Several different dental devices are available. A trained dental professional such as a dentist or orthodontist should fit these devices. Devices include:

Mandibular advancement device (MAD). This is the most widely used dental device for sleep apnea. It is similar in appearance to a sports mouth guard. MAD forces the lower jaw forward and down slightly, which keeps the airway open.
Tongue retraining device (TRD). This is a splint that holds the tongue in place to keep the airway as open as possible.

Patients fitted with one of these devices should have a check-up early on to see if it is working; short-term success usually predicts long-term benefits. It may need to be adjusted or replaced periodically.

MAD and similar devices seem to offer the following benefits:

Significant reduction in apneas for those with mild-to-moderate apnea, particularly if patients sleep either on their backs or stomachs. They do not work as well if patients lie on their side. The devices may also improve airflow for some patients with severe apnea.
Improvement in sleep in many patients.
Improvement and reduction in the frequency of snoring and loudness of snoring in most (but not all) patients.
Higher compliance rates than with CPAP.

According to a 2006 review, dental devices help control sleep apnea in 52% of treated patients. A 2002 report indicated that long-term use of a dental device achieved an 81% success rate in apnea improvement, which was significantly higher than the 53% success rate noted for uvulopalatopharyngoplasty (UPPP), the standard surgical treatment. There were also few complications with the dental device.

Dental devices, including MAD, are not as effective as CPAP therapy. The cost of these devices tends to be high. Side effects associated with dental devices include:

Nighttime pain, dry lips, tooth discomfort, and excessive salivation. In general, these side effects are mild, although over the long term they cause nearly half of patients stop using dental devices. Devices made of softer materials may produce fewer side effects.
Permanent changes in the position of the teeth or jaw have occurred in some cases of long-term use. Patients should have regular visits with a health professional to check the devices and make adjustments.
In a small percentage of patients, the treatment may worsen apnea. Patients should be monitored with polysomnography (sleep lab evaluation) before and after therapy and when apnea symptoms worsen or recur.

An orthodontic treatment called rapid maxillary expansion, in which a screw device is temporarily applied to the upper teeth and tightened regularly, may help patients with sleep apnea and a narrow upper jaw. This nonsurgical procedure helps to reduce nasal pressure and improve breathing.

Surgery

Surgery is sometimes recommended, usually by throat specialists, for severe obstructive sleep apnea. A patient should be sure to seek a second opinion from a specialist in sleep disorders. Few randomized clinical trials, the gold standard of medical research, have been conducted to verify the long-term efficacy of sleep apnea surgery.

The Procedure. Surgery known as uvulopalatopharyngoplasty (UPPP) removes soft tissue on the back of the throat. Such tissue includes all or part of the uvula (the soft flap of tissue that hangs down at the back of the mouth) and parts of the soft palate and the throat tissue behind it. If tonsils and adenoids are present, they are removed. The surgery typically requires a stay in the hospital.

The Goal of Surgery. The goal of UPPP is threefold:

Increase the width of the airway at the throat's opening
Block some of the muscle action in order to improve the ability of the airway to remain open
Improve the movement and closure of the soft palate

Success Rates. Success rates for sleep apnea surgery are rarely higher than 65% and often deteriorate with time, averaging about 50% or less over the long term. Few studies have been conducted on which patients make the best candidates. Some studies suggest that surgery is best suited for patients with abnormalities in the soft palate, which may or may not involve the tonsils. Results are poor if the problems involve other areas or the full palate. In such cases, CPAP is superior. In one study, sleeping on the side (rather than the back) after surgery significantly boosted success rates.

Complications. Uvulopalatopharyngoplasty is among the most painful treatments for sleep apnea, and recovery takes several weeks. It is recommended only for select patients with severe obstructive sleep apnea. The procedure also has a number of potentially serious complications. In fact, in one study, 42% of patients had complaints about the procedure. Some complications include:

Infection. In one study, this complication was so common that 40% of patients needed another operation because of it. Preventive antibiotics administered an hour before surgery can help reduce this risk.
Impaired function in the soft palate and muscles of the throat.
Mucus in the throat.
Changes in voice frequency.
Swallowing problems.
Regurgitation of fluids through the nose or mouth.
Impaired sense of smell.
Failure and recurrence of apnea. In such cases, CPAP is often less effective afterward, although one study found that oral appliances (plastic mouth retainer-like devices) may still help.

Experts estimate that in general about 1.6% of patients experience serious complications. Many of these complications can be avoided with proper technique and experienced surgeons. However, a patient’s health status may also affect outcomes. According to a 2006 study, patients are more likely to experience complications if they have severe sleep apnea, are overweight, have other medical problems, or undergo other surgical procedures at the same time as UPPP.

A variation on UPPP called laser-assisted uvulopalatoplasty (LAUP) is being increasingly performed to reduce snoring. It removes less tissue at the back of the throat than UPPP and can be done in a doctor's office. At this time, however, long-term success rates from LAUP are very modest, particularly for reducing apneas. Some doctors, in fact, are concerned that if LAUP eliminates snoring, they may miss a diagnosis of apnea in patients who have the more serious condition.

More than 50% of patients complain of throat dryness after surgery. Throat narrowing and scarring have also been reported. In a minority of patients, snoring becomes worse afterward.

The pillar palatal implant is a noninvasive surgical treatment for mild-to-moderate sleep apnea and snoring. It helps reduce the vibration and movement of the soft palate. In this procedure, a doctor inserts 3 short pieces of polyester string into the soft palate. The procedure can be performed in a doctor’s office and takes about 10 minutes. Unlike uvulopalatopharyngoplasty (UPPP), the pillar procedure requires only local anesthesia. Studies indicate it works as well as UPPP, with less pain and quicker recovery time.

Tracheostomy used to be the only treatment for sleep apnea. It is quite straightforward:

The surgeon makes an opening through the neck into the windpipe and inserts a tube.
It is almost 100% successful, but it requires a quarter-size opening in the throat. This produces a number of medical and psychological problems associated with recovery.

Today, this operation is performed rarely, usually only if sleep apnea is life-threatening.

A technique called radiofrequency ablation uses radiofrequency energy to shrink tissues in the upper airways:

The radio waves heat, stiffen, and shrink a small amount of tissue at the base of the tongue.
The therapy takes about 20 minutes and can be done in a doctor's office.
It typically requires 10 treatments within five or six sessions. (A newer form requires fewer treatment sessions, and it appears to be effective.)
It is far less invasive than standard surgery and results in far less pain and fewer complications. Discomfort can be controlled with simple pain relievers.

Studies reporting significant improvement in reduced snoring and less daytime sleepiness for some patients although, as with other surgeries, the benefits may be short term in the majority of patients. It may be helpful for mild obstructive sleep apnea.

Other surgical procedures may be appropriate to correct facial abnormalities or obstructions that cause sleep apnea. They may be used alone or combined with each other or with UPPP. They include:

Tongue advancement, in which an opening is cut where the tongue joins the jawbone and the area is pulled forward.
Genioplasty, which is plastic surgery on the chin.
Hyoid surgery, in which the movable bone underneath the chin is moved forward, pulling the tongue muscle along with it.
Maxillary or maxillomandibular advancement (MMA), which moves the upper (maxilla) or lower (mandible) jawbone forward. A survey of patients who had MMA found that the surgery changed their facial appearance, but most people thought it was a change for the better.
Surgery for nasal obstructions (such as a deviated septum) that contribute to snoring and other symptoms.

Adenotonsillectomy, or surgical removal of the tonsils and adenoids, is a first-line treatment for children and adolescents with sleep apnea. It cures the condition in 75 - 100% of cases. Two studies, published in 2005, suggested that adenotonsillectomy can significantly improve quality of life for children with obstructive sleep apnea.

Complications include respiratory illness, which occurs in about 25% of children after the surgery. The highest risk for respiratory complications is associated with:

Age under 3 years old
Severe sleep apnea
Heart complications
Failure to thrive
Obesity
Prematurity
Recent lung infections
Certain facial structures
Neuromuscular disease

The procedure may fail to improve apnea in some patients, such as those with very severe disease. Such children are candidates for continuous positive airway pressure (CPAP) therapy.

Removal of the tonsils and adenoids alone is not an effective treatment for adults with sleep apnea, although the procedure may be effective when combined with UPPP surgery.

Resources

www.sleepapnea.org -- American Sleep Apnea Association
www.nhlbi.nih.gov -- National Heart, Lung, and Blood Institute
www.aasmnet.org -- American Academy of Sleep Medicine
www.sleepfoundation.org -- National Sleep Foundation
www.nhlbi.nih.gov/about/ncsdr -- National Center on Sleep Disorders Research
www.sleepeducation.com -- Sleep Education from the American Academy of Sleep Medicine
www.wfsrs.org -- World Federation of Sleep Research Societies

References

Bradshaw DA, Ruff GA, Murphy DP. An oral hypnotic medication does not improve continuous positive airway pressure compliance in men with obstructive sleep apnea. Chest. 2006 Nov;130(5):1369-76.

Kezirian EJ, Weaver EM, Yueh B, Khuri SF, Daley J, Henderson WG. Risk factors for serious complication after uvulopalatopharyngoplasty. Arch Otolaryngol Head Neck Surg. 2006 Oct;132(10):1091-8.

Peppard PE, Szklo-Coxe M, Hla KM, Young T. Longitudinal association of sleep-related breathing disorder and depression. Arch Intern Med. 2006 Sep 18;166(16):1709-15.

Weaver TE, Maislin G, Dinges DF, Bloxham T, George CF, Greenberg H, et al. Relationship between hours of CPAP use and achieving normal levels of sleepiness and daily functioning. Sleep. 2007 Jun 1;30(6):711-9.

Review Date:
7/18/2007
Reviewed By:
Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital.

A.D.A.M. Copyright

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