- Research confirms the dangers when your cholesterol levels are too high.
- The Framingham Heart Study established that high blood cholesterol is a risk factorFramingham study showed that the higher your cholesterol level, the greater your risk.
for coronary heart disease (CHD). Results of the - Several studies have confirmed a direct link between high blood cholesterol and CHD. The Lipid Research Clinics-Coronary Primary Prevention Trial (LRC-CPPT) first showed that lowering total and LDL (bad) cholesterol levels significantly reduces coronary heart disease. A series of more recent trials of cholesterol-lowering using statin drugs have conclusively demonstrated that lowering total cholesterol and LDL cholesterol reduces your chance of having a heart attack, needing bypass surgery or angioplasty, and dying of CHD-related causes.
- Recent studies have shown that lowering cholesterol in people without heart disease greatly reduces their risk for developing heart disease in the first place. This is true for those with high cholesterol levels and for those with average cholesterol levels.
- In 1994, the Scandinavian Simvastatin Survival Study (4S) was the first study to show that people who took the cholesterol-lowering class of drugs called statins (in this case, simvastatin) reduced their risk for major CHD events (such as a heart attack) by 34%, CHD deaths by 42%, and all deaths by 30% in people with known coronary heart disease and high blood cholesterol levels, compared with people who were given a placebo (a dummy pill that looks exactly like the medication being tested). This has been called "secondary prevention," or prevention of a second heart attack, because the study involved people with known heart disease, many of whom had already had at least one heart attack.
- A 1995 study called the West of Scotland Coronary Prevention Study (WOSCOPS) found that lowering cholesterol reduced the number of heart attacks and deaths from cardiovascular causes in men with high blood cholesterol levels who had not had a heart attack. For 5 years, more than 6,500 men with total cholesterol levels of 249-295 mg/dL were given either a cholesterol-lowering drug or a placebo along with a cholesterol-lowering diet. The drug that was given is known as a statin (pravastatin), and it reduced total cholesterol levels by 20% and LDL (bad) cholesterol levels by 26%. The study found that the overall risk of having a nonfatal heart attack or dying from CHD was reduced by 31% in those who received the statin. The need for bypass surgery or angioplasty was reduced by 37%, and deaths from all cardiovascular causes were reduced by 32%. A very important finding was that deaths from causes other than heart disease were not increased, and overall deaths from all causes were reduced by 22%. This is called primary prevention because the study subjects had not previously had a heart attack.
- In 1996, the CARE study of CHD patients with "normal" cholesterol (LDL average of 138 mg/dL) values and a recent heart attack was associated with 24% reduction in CHD events. Overall death rates were not affected. The drug used was pravastatin.
- In 1998, the results of the Air Force/Texas Coronary Atherosclerosis Prevention Study (AFCAPS/TexCAPS) showed that lowering cholesterol in generally healthy men and women (no previous heart disease) with average cholesterol levels reduced their risk for a first-time major coronary event (such as a heart attack) by 37%. Lovastatin was the drug used in this study.
- In the 1998 LIPID study, men and women with known CHD and mild-to-moderate elevations of LDL lowered their risk of death by 22%, CHD deaths by 24%, and death by CHD or nonfatal heart attack by 24%. Pravastatin was the drug used in this study.
- The Heart Protection Study, published in 2002, examined men and women of all ages at high risk for heart disease irrespective of their cholesterol levels. Simvastatin treatment reduced CHD events by 24%. This study has caused some experts to suggest that everyone at high risk for CHD would benefit from statin therapy, regardless of their blood cholesterol levels.
- The National Health and Nutrition Examination Survey III (NHANES III), carried out from 1988-1991, discovered that 26% of American adults had high blood cholesterol concentrations, and 49% had desirable values.
