High Cholesterol Cholesterol is a type of fat-like substance made by the liver and found in some of the foods we eat. It's carried in the blood in the form of lipoproteins (fat covered in proteins). There are two kinds of lipoproteins. Low-density lipoproteins (LDLs) tend to build up along the walls of the arteries. They are sometimes referred to as the "bad cholesterol" because high levels are associated with an increased risk for artery blockages.

High-density lipoproteins (HDLs) carry cholesterol from the body to the liver to be broken down and eliminated. Since HDLs help reduce cholesterol levels, they are often referred to as the "good cholesterol."

In some people, excess cholesterol builds up on the inside walls of the arteries. The waxy substance eventually can form into hardened plaque. In the heart, accumulation of plaque can interfere with the flow of blood to the heart muscle (coronary artery disease). The plaque can break open, or rupture, and release fat and cholesterol into the blood. A blood clot can form in the narrowed area of plaque and block the flow of blood. The part of the heart muscle fed by that artery is deprived of oxygen and dies. This is a heart attack, or myocardial infarction. A heart attack can also occur if the plaque builds up enough to close off the artery.

According to the American Heart Association, more than 99 million Americans have high cholesterol and may be at risk for heart disease. Ideally, total cholesterol levels should be less than 200 mg/dL of blood. LDL cholesterol (the bad cholesterol) should be less than 100 mg/dL. Since HDL cholesterol helps to keep LDL levels under control, higher HDL levels are advised. An HDL level of 60 mg/dL is considered to be protective against heart disease.

Statins to Reduce Cholesterol Levels Statins are a group of drugs that have been prescribed to improve cholesterol levels. They work by blocking an enzyme in the liver (HMG C-A reductase) slowing down the body's natural production of cholesterol. The drugs may also help the body remove LDL cholesterol that has accumulated on arterial walls.

Researchers say statins are now one of the most widely prescribed classes of medication in this country. Six statins are currently approved for use in the U.S.: Lipitor® (atorvastatin), Lescol® (fluvastatin), Mevacor® (lovastatin), Pravachol® (pravastatin), Zocor® (simvastatin) and Crestor® (rosuvastatin). The effects of the drugs vary somewhat. Some are better at lowering total cholesterol while others are better for lowering LDL cholesterol.

Research suggests, for some people, use of statins can reduce the risk of heart attack and stroke. However, there are some risks associated with the medications. The most common side effects can include nausea, diarrhea, gas, stomach upset and constipation. Some patients may experience headache, rash, dizziness or sleep problems.

About one percent of patients taking statins experience an increase in liver enzymes, which could be an indication of problems with liver function. In some cases, patients may need to discontinue use of statins.

Some patients taking statins develop muscle pain and tenderness. In very rare cases, muscle cells break down and release a protein, called myoglobin. This serious condition is known as rhabdomyolysis. The myoglobin protein can impair kidney function and lead to irreversible kidney failure and heart arrhythmias.

Other Uses for Statins Research suggests statins may have benefits that go beyond controlling cholesterol and reducing the risk of heart attack and stroke. At the University of Alabama at Birmingham, investigators are studying the effects of a statin drug on Alzheimer's disease. The theory is that cholesterol in brain cells may play a role in the brain changes that lead to Alzheimer's.

In the 18-month study, Alzheimer's patients will be randomized to receive a statin or placebo. At the end of the trial, doctors will compare the two groups to see if the statin medication was able to slow down the progression of Alzheimer's deterioration.

Other studies have been conducted to determine if statins may have any benefit for conditions like macular degeneration, glaucoma, cancer, multiple sclerosis, hypertension, heart failure and rheumatoid arthritis.

Currently, there is still no solid evidence to show that statins will have any protective effect beyond their cholesterol-lowering benefits. Thus, those who aren't currently taking the drugs shouldn't ask for them until more substantial evidence has been gathered.

For information about particular statin drugs: Lipitor® (Atorvastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a600045.html Lescol® (Fluvastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a694010.html Mevacor® (Lovastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a688006.html Pravachol® (Pravastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a692025.html Zocor® (Simvastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a692030.html Crestor® (Rosuvastatin), http://www.nlm.nih.gov/medlineplus/druginfo/medmaster/a603033.html

For information about high cholesterol, American Heart Association, http://www.americanheart.org, or contact your local chapter National Heart, Lung and Blood Institute, http://www.nhlbi.nih.gov