A primary event (MI or death) occurred in 275 of the 1267 placebo patients (21.7%) and in 219 of the 1264 gemfibrozil patients (17.3%). The overall reduction in the risk of an event was 4.4 percentage points, and the reduction in relative risk was 22% (95% confidence interval, 7% to 35%; p=0.006). A 24% relative risk reduction occurred in the combined outcome of death from coronary heart disease, nonfatal myocardial infarction, and stroke (p<0.001). Gemfibrozil therapy resulted in a significant reduction in the risk of major cardiovascular events in patients with coronary disease whose primary lipid abnormality was a low HDL cholesterol level. The findings suggest that the rate of coronary events is reduced by raising HDL cholesterol levels and lowering levels of triglycerides without lowering LDL cholesterol levels.