The Representation of Females in Studies on Antihypertensive Medication over the Years: A Scoping Review

Background: The leading global risk factor for cardiovascular-disease-related morbidity and mortality is hypertension. In the past decade, attention has been paid to increase females' representation. The aim of this study is to investigate whether the representation of females and presentation of sex-stratified data in studies investigating the effect of antihypertensive drugs has increased over the past decades.

Methods: After systematically searching PubMed and Embase for studies evaluating the effect of the five major antihypertensive medication groups until May 2020, a scoping review was performed. The primary outcome was the proportion of included females. The secondary outcome was whether sex stratification was performed.

Results: The search resulted in 73,867 articles. After the selection progress, 2046 studies were included for further analysis. These studies included 1,348,172 adults with a mean percentage of females participating of 38.1%. Female participation in antihypertensive studies showed an increase each year by 0.2% (95% CI 0.36-0.52), p < 0.01). Only 75 (3.7%) studies performed sex stratification, and this was the highest between 2011 and 2020 (7.2%).

Conclusion: Female participation showed a slight increase in the past decade but is still underrepresented compared to males. As data are infrequently sex-stratified, more attention is needed to possible sex-related differences in treatment effects to different antihypertensive compounds.