The following is a summary of Underrepresentation of Women in Reduced Ejection Heart Failure Clinical Trials With Improved Mortality or Hospitalization,” published in the January 2024 issue of Cardiology by Ekpo et al.
Sex-specific differences in outcomes for heart failure (HF) with reduced ejection fraction (HFrEF) are well-documented, impacting randomized clinical trials (RCTs) that guide therapy guidelines through reductions in cardiovascular mortality or hospitalization for heart failure (HHF).
Researchers conducted a retrospective study to assess the inclusion of women in HFrEF RCTs focusing on reduced all-cause or cardiovascular mortality and hospitalization for HHF.
The study searched several databases, including Cumulative Index to Nursing and Allied Health Literature, Excerpta Medica dataBASE, Medical Literature Analysis and Retrieval System Online, and PubMed. They looked for RCTs focusing on HFrEF (published between 1980 and 2021). These trials had to demonstrate a statistically significant improvement in either mortality or hospitalization due to HHF due to the intervention. To assess the representativeness of the included trials, they employed the participation-to-prevalence ratio (PPR), considering a PPR range of 0.8 to 1.2 indicative of representative sampling.
The results showed that out of the 33 RCTs analyzed, women comprised merely 23.2% of the total enrolled participants (n = 24,366/104,972), varying between 11.4% and 40.1% across trials. The overall PPR was calculated at 0.58, with individual trial PPR estimates ranging from 0.29 to 1.00. Only 5 trials (15.2%) had a PPR indicative of women’s representation aligning with the disease population. There was no significant change observed in representation over time. The proportion of women in trials conducted in North America significantly exceeded those in European trials (P=0.03). A higher proportion of women were in industry-sponsored trials than those funded by government sources (P=0.05).
Investigators concluded that the underrepresentation of women in HFrEF trials weakens understanding of sex differences in treatment outcomes, demanding concerted efforts for equitable inclusion.