Objectives: The objective was to assess the effect of menopausal hormonal therapy (MHT) on all-cause and cause-specific mortality.
Methods: We conducted a comprehensive search of several databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Database of Systematic Reviews, and Scopus) from inception until August 2013. We included randomized controlled trials (RCTs) of more than 6 months of duration comparing MHT with no treatment. Pairs of independent reviewers selected trials, assessed risk of bias and extracted data. We estimated risk ratios (RRs) and 95% confidence intervals (CIs) using the random-effects model.
Results: We included 43 RCTs at moderate risk of bias. Meta-analysis showed no effect on mortality (RR 0.99 [95% CI, 0.94-1.05]), regardless of MHT type or history of preexisting heart disease. No association was found between MHT and cardiac death (RR 1.04 [95% CI 0.87-1.23]) or stroke (RR 1.49 [95% CI 0.95-2.31]). Estrogen plus progesterone use was associated with a likely increase in breast cancer mortality (RR 1.96 [95% CI 0.98-3.94]), whereas estrogen use was not. MHT use was not associated with mortality of other types of cancer. In 5 trials, MHT was likely started at a younger age: 2 RCTs with mean age less than 60 and 3 RCTs with MHT started less than 10 years after menopause. Meta-analysis of these 5 RCTs showed a reduction of mortality with MHT (RR 0.70 [95% CI 0.52-0.95]).
Conclusion: The current evidence suggests that MHT does not affect the risk of death from all causes, cardiac death and death from stroke or cancer. These data may be used to support clinical and policy deliberations about the role of MHT in the care of symptomatic postmenopausal women.