Spironolactone use is associated with improved outcomes in heart failure with mid‐range ejection fraction

AIMS: Spironolactone has been shown to improve outcomes in patients with heart failure (HF) with reduced ejection fraction (EF). We investigated whether the discharge use of spironolactone could be associated with better long‐term outcomes among patients with HF with mid‐range EF (HFmrEF). METHODS AND RESULTS: We analysed HFmrEF (left ventricular EF 40–49%) patients enrolled in the Japanese Cardiac Registry of Heart Failure in Cardiology, which prospectively studied the clinical characteristics, treatments, and long‐term outcomes of patients hospitalized due to HF. Patients were divided into two groups according to the use of spironolactone at discharge. The primary outcome was a composite of all‐cause death or HF rehospitalization. A total of 457 patients had HFmrEF. The mean age was 69.3 years and 286 (62.6%) were male. Among them, spironolactone was prescribed at discharge in 158 patients (34.6%). Chronic kidney disease (7.6% vs. 16.8%, P = 0.007) was less prevalent and loop diuretics (89.2% vs. 70.2%, P < 0.001) were more often prescribed in patients with spironolactone. During a mean follow‐up of 2.2 years, patients with spironolactone had a lower incidence rate of the primary outcome than those without it (171.5 vs. 278.8 primary outcome per 1000 patient‐years, incidence rate ratio 0.61, 95% confidence interval 0.44–0.86; P = 0.004). After multivariable adjustment, spironolactone use at discharge was associated with a significant reduction in the composite of all‐cause death or HF rehospitalization (adjusted hazard ratio 0.63, 95% confidence interval 0.44–0.90, P = 0.010). CONCLUSIONS: Among patients with HF hospitalized for HFmrEF, spironolactone use at discharge was associated with better long‐term outcomes.