EFFECTS OF BETA-BLOCKER THERAPY ON MORTALITY IN PATIENTS WITH HEART-FAILURE - A SYSTEMATIC OVERVIEW OF RANDOMIZED CONTROLLED TRIALS

Aims Several randomized trials have reported that beta-blocker therapy improves left ventricular function and reduces the rate of hospitaliz ation in patients with congestive heart Failure. However, most trials were individually too small to assess reliably the effects of treatmen t on mortality. In these circumstances a systematic overview of all tr ials of beta-blocker therapy in patients with congestive heart failure may provide the most reliable guide to treatment effects. Methods and results Details were sought from all completed randomized trials of o ral beta-blocker therapy in patients with heart failure of ally aetiol ogy. In particular, data on mortality were sought from all randomized patients for the scheduled treatment period. The typical effect of tre atment on mortality was estimated From an overview in which the result s of all individual trials were combined using standard statistical me thods. Twenty-four randomized trials, involving 3141 patients with sta ble congestive heart failure were identified. Complete data on mortali ty were obtained from all studies, and a total of 297 deaths were docu mented during an average of 13 mouths of follow-up. Overall, there was a 31% reduction in the odds of death among patients assigned a beta-b locker (95% confidence interval 11 to 46%, 2P=0.0035), representing an absolute reduction in mean annual mortality From 9.7% to 7.5%. The ef fects on mortality of vasodilating beta-blockers (47% reduction SD 15) , principally carvedilol. were nonsignificantly greater (2P=0.09) than those of standard agents (18% reduction SD 15), principally metoprolo l. Conclusions Beta-blocker therapy is likely to reduce mortality in p atients with heart failure. However, large-scale, long-term randomized trials are still required to confirm and quantify more precisely the benefit suggested by this overview.