Long-term effect of gemfibrozil on coronary heart disease risk profile of patients with primary combined hyperlipidaemia.

BACKGROUND

The purpose of the present study was to assess the effect of gemfibrozil on 12 independent coronary heart disease risk factors in patients with primary combined hyperlipidaemia.

METHODS

One hundred and five patients (62 men and 43 women), aged 53.2 +/- 4.8 years, were studied. The 10-year probability of myocardial infarction for the patients was calculated using the TYPMI (Ten-Year Probability for Myocardial Infarction) computer program, which is constructed to co-evaluate 12 independent coronary artery disease risk factors. All patients followed a lipid-lowering diet and placebo for 3 months. At month 0, the patients received 1200 mg gemfibrozil daily, divided into two equal doses, for a period of 12 months. At months -3, 0, 1, 3, 6, and 12, total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides [only if the low-density lipoprotein (LDL) cholesterol to high-density lipoprotein cholesterol ratio was above 5], systolic blood pressure, plasma glucose, left ventricular mass index, and plasma fibrinogen were measured. Smoking habits, sex, age, physical activity and family history of coronary heart disease were also evaluated. The mean 10-year probability of myocardial infarction of all 105 patients at month 0 was 27.8%. This was significantly higher than the anticipated probability (10.4%, P < 0.001), resulting from an age- and sex-matched group of general population.

RESULTS

During the third month of treatment, the following changes were recorded: total cholesterol -17%, LDL cholesterol -18%, very-low-density lipoprotein (VLDL) cholesterol -45%, HDL cholesterol 20%, triglycerides -43%, apoprotein B -12%, apoprotein A-I 9% and plasma fibrinogen -21%. The estimated risk for myocardial infarction was reduced to 13.5% (delta m = -51%). All changes were significant and sustained until the twelfth treatment month. None of the patients were withdrawn from the study because of adverse effects of the treatment.

CONCLUSION

Gemfibrozil reduces the estimated risk for myocardial infarction in patients with primary combined hyperlipidaemia at a level no different from the one of the general population. This beneficial effect of gemfibrozil, which was expressed by the third month and was evident for some time afterwards, was attributed to a significant reduction of triglyceride and fibrinogen levels, an increase of HDL cholesterol concentrations and a moderate decrease of total cholesterol and LDL cholesterol levels.