Can older patients with stable cardiovascular disease benefit from the same cholesterol lowering drugs used by younger patients? The answer is yes, according to a study report in the July 3, 2007 issue of the Annals of Internal Medicine.
The key to beneficial treatment appears to be dosage, says lead author Nanette K. Wenger, MD, professor of medicine in the Division of Cardiology, Emory University School of Medicine, and chief of cardiology at Grady Memorial Hospital.
"The exciting part of this study is that not only do older patients benefit from statin therapy, but aggressive use of high-dose statins to reduce the bad cholesterol, the LDL cholesterol, to levels lower than 100 mg/dL, provided additional benefit," says Dr. Wenger. "The study participants had a relative reduction in risk of 19 percent for a major cardiovascular event with high-dose compared with low-dose atorvastatin. The important feature is that this occurred without any evidence of increase in risk from the high dose."
In the study funded by drug manufacturer Pfizer, researchers studied 3,809 patients with a baseline age of 65 that were enrolled in a randomized trial of 10,001 patients with known coronary artery disease. Patients were randomly assigned to receive daily doses of either 80 mg or 10 mg of the statin drug Lipitor, and then were monitored for nearly five years.
Cholesterol is a waxy, fat-like substance that comes from two sources, in two forms. Produced primarily in the liver, our bodies need cholesterol to maintain healthy cell walls, make hormones, vitamin D and the bile acids which aid in fat digestion.
Cholesterol also comes from the foods that we eat. It has two forms: HDL, high-density lipoprotein "good" cholesterol and LDL, low-density lipoprotein "bad" cholesterol. High cholesterol or too much LDL is one of the risk factors for heart disease. High blood cholesterol itself does not cause symptoms, so even if a person looks and feels fine there may still be risk factors.
High cholesterol results in thick plaque deposits built up in the walls of arteries. Over time, this buildup causes arteries to become narrowed and blood flow to the heart is slowed down or blocked. The result can be a stroke or a heart attack.
Previous studies have shown statin drugs are effective for lowering LDL cholesterol levels in patients. The drugs work by interrupting the formation of cholesterol circulating in the blood. This study is the first to compare the effects of 80 mg versus 10 mg doses of the same statin formulation Lipitor in older patients. Earlier data show the minimum dosage 10 mg can reduce LDL levels 30 percent to 40 percent while the maximum dosage 80 mg can lower LDL levels by 50 percent.
"This reinforces what I have been doing clinically for my older patients, and that is treating them as aggressively as patients younger than 65 years of age." says Dr. Wenger. According to the American Heart Association, over 105 million American adults have total blood cholesterol values of 200 mg/dL and higher, andÊ36.6 million American adults have levels of 240 or above. Doctors consider total cholesterol levels of 240 mg/dL or greater high in adults and levels from 200 to 239 mg/dL borderline-high.
"The bottom line message for older patients who have coronary heart disease and who are on a cholesterol-lowering drug, ask your physician if your statin dose is adequate to allow you to reach the goal level for the bad cholesterol (LDL-C) of less than 100 mg/dL for all coronary patients, and less than 70 mg for those at very high risk--and many older patients are at very high risk," notes Dr. Wenger.