20 Aug How strong is the evidence for use of beta-blockers as first-line therapy for hypertension? Systematic review and meta-analysis
Hazel A. Bradleya, Charles Shey Wiysongeb, Jimmy A. Volminkc, Bongani M. Mayosib and Lionel H. Opied
Objective To quantify the effect of first-line antihypertensive treatment with beta-blockers on mortality, morbidity and withdrawal rates, compared with the other main classes of antihypertensive agents.
Methods We identified eligible trials by searching the Cochrane Controlled Trials Register, Medline, Embase, reference lists of previous reviews, and contacting researchers. We extracted data independently in duplicate and conducted meta-analysis by analysing trial participants in groups to which they were randomized, regardless of subsequent treatment actually received.
Results Thirteen trials with 91 561 participants, meeting inclusion criteria, compared beta-blockers to placebo (four trials; n U 23 613), diuretics (five trials; n U 18 241), calcium-channel blockers (CCBs) (four trials; n U 44 825), and renin-angiotensin system (RAS) inhibitors, namely angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (three trials; n U 10 828). Compared to placebo, beta-blockers reduced the risk of stroke (relative risk 0.80; 95% confidence interval 0.66-0.96) with a marginal fall in total cardiovascular events (0.88, 0.79-0.97), but did not affect all-cause mortality (0.99, 0.88-1.11), coronary heart disease (0.93, 0.81-1.07) or cardiovascular mortality (0.93, 0.80-1.09). The effect on stroke was less than that of CCBs (1.24, 1.11-1.40) and RAS inhibitors (1.30, 1.11-1.53), and that on total cardiovascular events less than that of CCBs (1.18, 1.08-1.29). In addition, patients