Sex differences in patients with heart failure and mildly reduced left ventricular ejection fraction

Clinical studies on heart failure with mildly reduced left ventricular ejection fraction (HFmrEF) have gradually increased. However, studies on the prognostic differences between men and women among patients with HFmrEF are few, and no evidence on sex differences in such patients exists. Therefore, we retrospectively assessed the data of patients with HFmrEF using propensity score-matched analysis (PSMA). A total of 1691 patients with HFmrEF were enrolled in the Outcome of Discharged HFmrEF Patients study (OUDI-HF study), which included 1095 men and 596 women. After propensity score matching, we compared the difference in cardiovascular (CV) events (cardiovascular death or heart failure readmission) and all-cause mortality at 90 days and 1 year after discharge between men and women using Kaplan–Meier analysis and Cox regression. After PSMA, men with HFmrEF were 2.2 times more likely to die at 90 days than women with HFmrEF [hazard ratio (HR) 1.88; 95% confidence interval (95% CI) 1.03–3.46; P = 0.041]. However, there was no difference in the 90-day CV events (HR 0.96; 95% CI 0.75–1.22; P = 0.718). Similarly, there was no difference in all-cause mortality (HR 1.16; 95% CI 0.81–1.65; P = 0.417) and CV events (HR 0.98; 95% CI 0.83–1.16; P = 0.817) between men and women after 1 year. Among the patients with HFmrEF, men had a higher 90-day risk of all-cause mortality than women after hospital discharge, and this risk disappeared after 1 year. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT05240118 (ESC Heart Failure. (2022). doi: 10.1002/ehf2.14044).