Results of the primary outcome measure and clinical events from the asymptomatic carotid artery progression study

The 3-hydroxy-3-methylglutaryi coenzyme A (HMGCoA) reductase inhibitors have proven to be more effective in reducing levels of low density lipoprotein (LDL) cholesterol and to be better tolerated than other lipid-lowering compounds. Most of the trials evaluating the effects of these new agents on progression of atherosclerosis have not included individuals asymptomatic for cardiovascular disease and who have LDL cholesterol levels at or below the limits established by the National Cholesterol Education Program for initiating treatment. The Asymptomatic Carotid Artery Progression Study (ACAPS) tested the effect of the HMG-CoA reductase inhibitor, lovastatin, on early-stage carotid atherosclerosis (as detected by B-mode ultrasonography) in 919 asymptomatic men and women, 40–79 years of age, who had LDL cholesterol levels between the 60th and 90th percentiles. Participants randomized into this double-blind, placebo-controlled, factorially designed study received lovastatin (20–40 mg/ day) or lovastatin-placebo and warfarin (1 mg/ day), or warfarin-placebo over a 3-year period. The progression of the mean maximum intimai-medial thickness (IMT) over 12 walls of both carotid arteries represented the primary outcome. Lovastatin treatment was associated with a reduction in progression of mean maximum IMT (p