Lipoproteins and coronary heart disease in the Helsinki Heart Study

Abstract

The changes in serum lipids in men treated with gemfibrozil in the Helsinki Heart Study, a controlled primary prevention trial of coronary heart disease, varied according to baseline lipid levels, type of dyslipidaemia, and treatment compliance. In subjects with the best treatment compliance, gemfibrozil induced mean decreases of 14% in total cholesterol, 15% in low density lipoprotein (LDL)-cholesterol, and 45% in triglycerides, and a mean increase of 14% in high density lipoprotein (HDL)-cholesterol, compared with placebo. These changes were significantly greater than those observed in the entire cohort. There was a strong association between baseline levels and the response to treatment (expressed as the difference in mmol l-1 between the gemfibrozil- and placebo-treated groups) for LDL-cholesterol and triglycerides. In contrast, the corresponding change in HDL-cholesterol was not dependent on the baseline level. Ultracentrifuge analysis in a subsample of the cohort revealed that gemfibrozil raised the level of HDL3-cholesterol but had little effect on HDL2-cholesterol. The gemfibrozil-associated reduction in the incidence of definite coronary events varied according to lipid values at baseline and their changes during treatment. The greatest reductions were seen in subjects with low initial HDL-cholesterol and high initial triglycerides. In the gemfibrozil group, the increase in HDL-cholesterol and decrease in LDL-cholesterol were associated with significantly lower risk of coronary events.