β-Blocker Use and Cardiovascular Outcomes in Hemodialysis: A Systematic Review

Rationale & Objective: There is conflicting evidence regarding the type of β-blockers to use in dialysis patients. This systematic review seeks to determine whether highly dialyzable β-blockers are associated with higher rates of cardiovascular events and mortality in hemodialysis patients than poorly dialyzable β-blockers. Study Design: A systematic review of the existing literature was conducted. A meta-analysis was performed using data from the selected studies. Setting & Study Populations: Participants were from the United States, Canada, and Taiwan. The mean ages of participants ranged from 55.9-75.7 years. Selection Criteria for Studies: We searched the Ovid MEDLINE database from 1990 to September 2020. Studies without adult hemodialysis participants and without comparisons of at least 2 β-blockers of different dialyzability were excluded. Data Extraction: Baseline and adjusted outcome data were extracted from each study. Analytical Approach: Random-effects models were used to calculate pooled risk ratios using fully adjusted models from individual studies. Results: Four cohort studies were included. Pooling fully adjusted models, highly dialyzable β-blockers did not influence mortality (HR, 0.94; 95% CI, 0.81-1.08; I² = 0.84) compared with poorly dialyzable β-blockers but were associated with a reduction in cardiovascular events (HR, 0.88; 95% CI, 0.83-0.93). There was significant heterogeneity between studies (I² = 0.35). Only 1 study reported on adverse events. Intradialytic hypotension was more common in those on carvedilol (a poorly dialyzable β-blocker) compared with those on metoprolol (a highly dialyzable β-blocker; adjusted incidence rate ratio, 1.10; 95% CI, 1.09-1.11). Limitations: No randomized controlled trials were identified. Each study used different analytic methods and different definitions for outcomes. Classifications of β-blockers varied. Only 1 study reported on adverse events. Conclusions: Pooled data suggest highly dialyzable β-blockers are associated with similar mortality events and fewer cardiovascular events compared with poorly dialyzable β-blockers.