HMG-COA REDUCTASE INHIBITOR THERAPY AND STROKE RISK REDUCTION - AN ANALYSIS OF CLINICAL-TRIALS DATA

Although associations of cholesterol and coronary heart disease (CHD) are well accepted, the association between cholesterol and stroke has been a subject of some confusion. Epidemiologic evidence suggests no a ssociation between plasma concentrations of cholesterol and stroke, an d earlier clinical trials were also negative. Two early meta-analyses of clinical trials designed to evaluate the effects of cholesterol low ering on CHD concluded that cholesterol lowering had no effect. More r ecently newer, more potent and better tolerated agents (HMG-CoA reduct ase inhibitors, reductase inhibitors) have become available and have b een tested for their efficacy in reducing cholesterol and CHD in both primary prevention and secondary prevention trials. Meta-analyses of t hese trials, in contrast to the earlier trials, reveal a powerful stat istically significant effect to reduce stroke as well as CHD in second ary prevention (30%); the direction of the effect is the same in trial s of primary prevention or trials that randomized patients with and wi thout CHD (mixed primary and secondary prevention trials) where the ri sk reductions for stroke, although not reaching statistical significan ce are 11 and 30%, respectively. An important difference in the newer analysis is the availability of several trials of secondary prevention in which low density lipoprotein cholesterol was lowered 25-30% and i n which CHD event reduction was similarly reduced by 30%. Mechanisms f or stroke reduction likely involve retardation of plaque progression i n the intracranial and extracranial carotid arteries, plaque stabiliza tion, and, in addition, stroke may be reduced partly as a consequence of CHD reduction. (C) 1998 Elsevier Science Ireland Ltd. All rights re served.