Twenty-one trials were included in the review (23,122 patients). Median follow-up was 12 months. All trials had a low risk of bias.
The conventional pair-wise meta-analysis that compared beta-blockers with all comparators showed reduced odds of mortality (OR 0.71, 95% CI 0.64 to 0.80; Ι²=33%; 21 studies). Similar evidence of benefit was found when examining only odds ratios from trials using shorter term follow-up and hazard ratios from trials using longer term follow-up. Bayesian network meta-analyses produced similar effect estimates.
Beta-blockers were associated with reducing the odds of cardiovascular death, reducing the odds of sudden death, and a change in left ventricular ejection fraction in conventional pair-wise and Bayesian network meta-analyses. Conventional pair-wise meta-analyses suggested that drug discontinuation was less likely for beta-blockers, but this was not confirmed in the Bayesian analyses.
In the Bayesian network meta-analyses, there was no evidence to indicate a substantial difference between individual beta-blockers for mortality or any other outcome. Exclusion of active controls did not change the conclusions of the analyses.
There was no evidence of substantial heterogeneity in most analyses. No evidence of publication bias was identified for any outcomes. The meta-regression suggested that dosage of beta-blockers did not impact on effect estimates
Further information from additional analyses were reported in the paper.