Association of Mineralocorticoid Receptor Antagonist Use With All-Cause Mortality and Hospital Readmission in Older Adults With Acute Decompensated Heart Failure

IMPORTANCE Scarce data are available on the association of mineralocorticoid receptor antagonist (MRA) use with outcomes in acute decompensated heart failure (ADHF). OBJECTIVE To investigate the association of MRA use with all-cause mortality and hospital readmission in patients with ADHF. DESIGN, SETTING, AND PARTICIPANTS This cohort study examines participants enrolled in the Kyoto Congestive Heart Failure (KCHF) registry, a physician-initiated, prospective, multicenter cohort study of consecutive patients admitted for ADHF, between October 1, 2014, and March 31, 2016, into 1 of 19 secondary and tertiary hospitals throughout Japan. To balance the baseline characteristics associated with the selection of MRA use, a propensity score-matched cohort design was used, yielding 2068 patients. Data analysis was conducted from April to August 2018. EXPOSURES Prescription of MRA at discharge from the index hospitalization. MAIN OUTCOMES AND MEASURES Composite of all-cause death or heart failure hospitalization after discharge. RESULTS Among 3717 patients hospitalized for ADHF, 1678 patients (45.1%) had received MRA at discharge and 2039 (54.9%) did not. After propensity score matching, 2068 patients (with a median [interquartile range] age of 80 [72-86] years, and of whom 937 [45.3%] were women) were included. In the matched cohort (n = 1034 in each group), the cumulative 1-year incidence of the primary outcome was statistically significantly lower in the MRA use group than in the no MRA use group (28.4% vs 33.9%; hazard ratio [HR], 0.81; 95% CI, 0.70-0.93; P=.003). Of the components of the primary outcome, the cumulative 1-year incidence of heart failure hospitalization was significantly lower in the MRA use group than in the no MRA use group (18.7% vs 24.8%; HR, 0.70; 95% CI, 0.60-0.86; P<.001), whereas no difference in mortality was found between the 2 groups (15.6% vs 15.8%; HR, 0.98; 95% CI, 0.82-1.18; P=.85). No difference in all-cause hospitalization was observed between the 2 groups (35.3% vs 38.2%; HR, 0.88; 95% CI, 0.77-1.01; P=.07). In additional analyses that stratified by left ventricular ejection fraction, the association of MRA use with the primary outcome was statistically significant in patients with left ventricular ejection fraction of 40% or greater. CONCLUSIONS AND RELEVANCE Use of MRA at discharge from ADHF hospitalization did not appear to be associated with lower mortality but was associated with a lower risk of heart failure readmission. This finding suggests that MRA treatment at discharge may have minimal, if any, clinical advantages.