Beta-blocker side-effects in clinical practice: A nationwide approach

Concerns regarding side-effects of beta-blockers (BBs) are frequent but data regarding the incidence of side-effects are conflicting and real-world data are sparse. Hence, we aimed to investigate the absolute and relative risks of BB side-effects in clinical practice. Using Danish nationwide registers, we included Danish hypertensive patients initiating anti-hypertensive treatment with a BB or calcium-channel blocker (CCB). We computed crude as well as standardized one-year risks and adjusted risk ratios of BB side-effects (depression, anxiety/insomnia, gastrointestinal side-effects, erectile dysfunction, and dizziness/fainting) compared with CCB treatment. We included 64,722 patients initiating treatment with a BB and 181,880 patients initiating treatment with a CCB. In patients initiated on BB, the standardized one-year risk of any outcome, erectile dysfunction exempt, was 13.7% (95% CI: 13.4%-13.9%). The one-year risk of specific BB side-effects was the highest for anxiety/insomnia (6.2%, 95% CI: 6.0%-6.3%), gastrointestinal side-effects (4.6%, 95% CI: 4.4%-4.7%), and erectile dysfunction (4.7%, 95% CI: 4.5%-4.9%). The risk of side-effects was consistently increased when comparing BB treatment with CCBs including depression (Risk Ratio [RR] 1.48, 95% CI 1.41-1.55), anxiety/insomnia (RR 1.53, 95% CI 1.47-1.59), gastrointestinal side-effects (1.31, 95% CI 1.25-1.36), and dizziness/fainting (RR 1.50, 95% CI 1.38-1.61), but not erectile dysfunction (RR 0.91, 95% CI, 0.85-0.96). In a large nationwide cohort, the incidence of BB side-effects was clinically relevant and consistently increased compared with CCBs with the exception of erectile dysfunction, which carried similar risks for both treatments.