β ‐Blockers in Heart Failure: Benefits of β ‐Blockers According to Varying Male Proportions of Study Patients

Background: In patients with heart failure (HF), b‐blockers reduce mortality. It's not known whether the beneficial effects of the b‐blockers were associated with the differing male proportions of study patients. It also remains to be clarified regarding the true beneficial effects of the 3 b‐blockers recommended by the guideline on mortality in the real world. Hypothesis: The benefits of b‐blockers in HF patients were sex‐related different. Methods: Randomized, placebo controlled clinical trials were included if they evaluated the beneficial effects of the three b‐blockers on mortality and on hospital admissions on an intention‐to‐treat basis, and lasted at least 3 months. Results: Twenty‐eighty trials with 14,829 patients were included. The b‐blockers significantly reduced all cause mortality by 29.6%, cardiac death by 29.8%, sudden death by 49.4%, respectively. The magnitude of benefits of b‐blockers in HF patients was increased with the increased male proportion. A similar magnitude of reduction in all cause mortality was observed among the three b blockers. A trend toward to reduced cardiac death was observed among the three b blockers, but only in bisoprolol was this statistically different (RR, 0.72; 95%CI, [0.59–0.87]). Metoprolol was significantly superior to carvedilol (P = 0.008) or bisoprolol (P = 0.034) in reduced sudden death. Conclusions: In patients with HF, the 3 commonly used b‐blockers significantly reduced mortality. Greater benefits of b‐blockers were observed in the higher male proportion studies. The metoprolol was significantly superior to carvedilol or bisoprolol in reduced sudden death. Additional trials are required to determine whether the benefits of b‐blockers will be observed in female HF patients. Clin. Cardiol. 2012 DOI: 10.1002/clc.21985 The authors have no funding, financial relationships, or conflicts of interest to disclose.