Randomized, controlled trial of secondary prevention of coronary sclerosisin normocholesterolemic patients using pravastatin: Two-year follow-up of the Prevention of Coronary Sclerosis Study

Background: Reducing serum total cholesterol (TC) levels using 3-hydroxy-3- methylglutaryl coenzyme A (HMGCoA) reductase inhibitors in hypercholesterol emic patients has been shown to reduce the incidence of complications of co ronary heart disease (CHD). However, few data are available on the potentia l benefit of reductions in serum cholesterol levels in normocholesterolemic patients with coronary atherosclerosis. Objective: The Prevention of Coronary Sclerosis Study is a single-center st udy designed to assess the effect of treatment with the HMG-CoA reductase i nhibitor pravastatin on progression and regression of angiographically docu mented coronary atherosclerosis in normocholesterolemic patients with CHD. Methods: A total of 329 patients aged < 70 years with CHD were enrolled and classified into 1 of 3 groups based on serum TC level: group 1, TC greater than or equal to 220 mg/dL; group 2, TC 180-219 mg/dL; and group 3, TC < 1 80 mg/dL. Patients in group 2 were randomized to 1 of 2 subgroups, 2a or 2b . Patients in groups 1 and 2a were given pravastatin 10 mg/d; patients in g roups 2b and 3 did not receive cholesterol-lowering drugs. The subsequent c oronary events of patients were followed for 2 years and reexamined by coro nary angiography (CAG). Both baseline and follow-up CAGs were analyzed by q uantitative coronary arteriography at a central laboratory. Results: Decreases in both mean segment diameter (MSD) and minimum obstruct ion diameter (MOD) in group 2a were significantly less than those in the co ntrol group 2b (P = 0.015 and P = 0.023, respectively). The effects on MSD and MOD in group 2a and the low-cholesterol reference group 3 were similar. The incidence of clinical events was 8.9%, 3.7%, 12.1%, and 10.0% in group s 1, 2a, 2b, and 3, respectively, with no significant differences in rates between groups 2a and 2b. Conclusion: The results of this study suggest that cholesterol-lowering the rapy with pravastatin may prevent progression of coronary atherosclerosis i n normocholesterolemic patients with CHD.