Reducing the risk for coronary events and stroke in hypertensive patients: Comments on present evidence

Therapeutic options for initial antihypertensive treatment include the four most popular classes of drugs: diuretics, beta blockers, angiotensin-converting enzyme (ACE) inhibitors, and calcium antagonists. The practitioner must decide which agent is appropriate for each patient, the main goal of treatment being to prevent stroke and coronary events—sudden death and myocardial infarction. A 40% reduction in stroke can probably be achieved with any antihypertensive treatment, but data show that it is much more difficult to reduce the risk of coronary events. Available evidence from studies in men indicates that certain beta blockers are superior to thiazide diuretics for the prevention of coronary events. Results from the Metoprolol Atherosclerosis Prevention in Hypertensives (MAPHY) Trial showed that the risk for coronary events was 24% lower in patients receiving metoprolol than in patients receiving diuretics (p>0.001), with beneficial effects in smokers as well as nonsmokers. Present data might suggest that different beta blockers may have different efficacy in preventing coronary events. Clinical trials have not yet produced long-term prognostic data on the effects of ACE inhibitors or calcium antagonists on the incidence of coronary events in hypertensive patients. Pooled data on calcium antagonist therapy in postmyocardial infarction patients indicate a trend toward higher mortality with calcium antagonists than with placebo. Because of the large number of hypertensive patients at increased risk for coronary events, the reduction in coronary events observed with some beta blockers may have important implications for clinical practice. The reduced risk for coronary events is probably independent of the reduction in blood pressure. Mechanisms currently under study include antiatherosclerotic effects, antithrombotic effects, anti-ischemic effects, and antifibrillatory effects.