Abstract
It has been accepted that the incidence of coronary artery disease (CAD) in patients with hypercholesterolemia (HC) can be lowered by reducing serum cholesterol levels. However, this concept is based mainly on the studies designed in the United States and Europian countries. There are few reports about the effects of medical treatment for HC in Japan.
The purpose of our study was to clarify the effects of and problems associated with medical treatment for HC in the Department of Geriatrics, Keio University Hospital.
We enrolled 230 patients treated medically with probucol, pravastatin, and/or other drugs including clofibrate, colestyramine. We excluded patients who had taken drugs for hypertension, diabetes mellitus, or CAD. Patients with undiagnosed chest pain and treated medically within 24 months were also excluded. Finally, 80 asymptomatic patients treated medically over 24 months were monitored for another 24 months. The endpoint of this study was the occurrence of CAD, cancer, or other cardiovascular disease.
The serum cholesterol level before treatment was 301±6 mg/d/ and it decreased to 242±5 mg/dl (-19%). LDL-cholesterol also decreased by 23%, but HDL-cholesterol didn't change with treatment. CAD developed in 6 patients during a 2-year follow-up period. There was no difference in total cholesterol, LDL-cholesterol, and triglyceride levels between patients with or without the development of CAD before treatment, at the start the of trial, and at the end of the trial; however, HDL-cholesterol levels at the start and end of the trial were significantly lower in patients with newly developed CAD. Therefore, 4 of 6 newly developed CAD patients were associated with an excessive decrease in HDL-cholesterol.
The sample size of our study was not large enough to draw definitive conclusions, but the results suggested that medical treatment with probucol, pravastatin, or other drugs was effective in lowering serum cholesterol and LDL-cholesterol levels. Our study also suggested that possible problems may be associated with the treatment of HC. Excessive decreases in HDL-cholesterol level during treatment could lead to the development of CAD, regardless of the choice of drug. The normalization of both total cholesterol and HDL-cholesterol levels could be equally important in treatment for HC.
