Sex differences in patients with acute decompensated heart failure in Japan: observation from the KCHF registry

AIMS: The association between sex and long‐term outcome in patients hospitalized for acute decompensated heart failure (ADHF) has not been fully studied yet in Japanese population. The aim of this study was to determine differences in baseline characteristics and management of patients with ADHF between women and men and to compare 1‐year outcomes between the sexes in a large‐scale database representing the current real‐world clinical practice in Japan. METHODS AND RESULTS: Kyoto Congestive Heart Failure registry is a prospective cohort study enrolling consecutive patients hospitalized for ADHF in Japan among 19 centres. Baseline characteristics, clinical presentation, management, and 1‐year outcomes were compared between men and women. A total of 3728 patients who were alive at discharge constituted the current study population. There were 1671 women (44.8%) and 2057 men. Women were older than men [median (IQR): 83 (76–88) years vs. 77 (68–84) years, P < 0.0001]. Hypertensive and valvular heart diseases were more prevalent in women than in men (28.0% vs. 22.5%, P = 0.0001; and 26.9% vs. 14.0%, P < 0.0001, respectively), whereas ischaemic aetiology was less prevalent in women than in men (20.0% vs. 32.5%, P < 0.0001). Women less often had reduced left ventricular ejection fraction (<40%) than men (27.5% vs. 45.1%, P < 0.0001). The cumulative incidence of all‐cause death or hospitalization for heart failure was not significantly different between women and men (33.6% vs. 34.3%, P = 0.71), although women were substantially older than men. After multivariable adjustment, the risk of all‐cause death or hospitalization for heart failure was significantly lower among women (adjusted hazard ratio: 0.84, 95% confidence interval: 0.74–0.96, P = 0.01). CONCLUSIONS: Women with heart failure were older and more often presented with preserved EF with a non‐ischaemic aetiology and were associated with a reduced adjusted risk of 1‐year mortality compared with men in the Japanese population.