Evidence-based medicine and treatment of hypertension in women: Results of trials

Purpose: The aim of this review is to summarize the evidence from randomized controlled trials and meta-analyses of hypertension treatment trials that included women in their study population and subsequent analyses. Results: Most early hypertension treatment trials did not include women in their study population, or did so in insufficient numbers to assess gender-specific outcomes. Women, particularly the elderly, were better represented in subsequent studies, but gender-specific results were not often reported and most trials were not designed or powered to detect gender differences in treatment responses and outcomes. In some studies where gender-specific results have been reported, gender differences have been observed, but the direction of the effect has generally been similar in men and women. Large meta-analyses of treatment trials have found similar relative risk reductions as a result of hypertension treatment, but lower absolute risk reductions in women compared to men. Absolute risk reductions are strongly related to baseline risk and have been demonstrated in virtually all subgroups of women except those with extremely low aggregate cardiovascular risk. While there are still limited data regarding treatment benefits for young women, no subset of women has been shown to experience net harm as a result of hypertension therapy. Conclusion: The design and implementation of future hypertension treatment trials should include the provision to assess gender-specific differences in treatment and outcomes.