Where Are we with Vitamin E?

Abstract

Oxidative modification of low-density lipoproteins appears to significantly enhance their role in atherogenesis. Inhibition of this process with naturally occurring antioxidants has been proposed as a mechanism to retard the progression of coronary artery disease. Vitamin E has been among those natural antioxidants found to reduce atherosclerotic lesion formation in animal models. Further supported by a substantial accumulation of observational epidemiologic data demonstrating an association between antioxidant vitamin intake and reduced risk of cardiovascular mortality, vitamin E has been examined in a number of case-control and prospective cohort studies as a potential agent in the primary and secondary prevention of morbidity and mortality from coronary artery disease. These efforts have generated a large body of evidence suggesting a protective role, but conflict in the data remains. In addition, even with large, well-conducted prospective epidemiologic studies, the potential effects of residual confounding may be on the same order of magnitude as the reported benefit. The several small randomized interventional trials and two larger placebo-controlled studies that have been completed to date leave some key questions unanswered. Currently ongoing are several large randomized interventional trials that will serve to further clarify the role of this promising agent in the primary and secondary prevention of atherosclerotic coronary disease.