Frailty in patients with acute decompensated heart failure in a super‐aged regional Japanese cohort

AIMS: The aim of this study was to investigate clinical characteristics of frail patients based on a comprehensive frailty assessment in patients hospitalized for acute decompensated heart failure (HF) (ADHF) in super‐aged regional Japanese cohort. METHODS AND RESULTS: We established the Kochi Registry of Subjects with Acute Decompensated Heart Failure (Kochi YOSACOI) study, which was a prospective multicentre community‐based cohort study in six participating hospitals in Kochi Prefecture, Japan. We enrolled 1061 patients (median age, 81 years; 50.0% men) hospitalized for ADHF between June 2017 and December 2019 in this registry. Patients were classified into the three groups by the severity of frailty using the Kihon Checklist: we identified frailty in 510 patients (53.7%), prefrailty in 293 patients (30.9%), and non‐frailty in 146 patients (15.4%). Compared with prefrail and non‐frail patients, frail patients were older (84 years interquartile range [IQR, 77–88] vs. 79 years [IQR, 69–86] and 72 years [IQR 65–81], P < 0.001) and more often had prior HF hospitalization (29.6% vs. 21.8% and 16.4%, P < 0.05), chronic kidney disease (81.6% vs. 71.7% and 61.0%, P < 0.01), anaemia (75.3% vs. 61.4% and 50.0%, P < 0.001), cerebrovascular accident (19.0% vs. 9.9% and 4.1%, P < 0.01). The proportion of patients with three or more comorbidities was larger in the frailty group than in the other groups (78.0% vs. 67.2% and 63.0%, P < 0.01). The frequency of functional decline in all domains increased with frailty status. Approximately 70% of frail patients were identified as functional decline in physical function and socialization domains. Fifty to sixty per cent of frail patients had functional decline in instrumental activities of daily living, cognitive function, and depression domains. The percentage of worsening walking ability during hospitalization was increasing with the frailty status (frailty, 27.5%; prefrailty, 21.8%; non‐frailty, 8.9%). In multivariate logistic regression analysis, frailty was associated with age [odds ratio (OR) 1.031, 95% confidence interval (CI) 1.011–1.052, P = 0.003], prior HF hospitalization (OR 1.789, 95% CI 1.165–2.764, P = 0.008), brain natriuretic peptide level at discharge (OR 1.001, 95% CI 1.000–1.001, P = 0.020) and prior cerebrovascular accident (OR 2.549, 95% CI 1.484–4.501, P < 0.001). CONCLUSIONS: More than half of patients with ADHF were frail and had functional decline across multiple domains, not only physical function domain. The Kihon Checklist provided useful and valuable information for easily identifying frail patients and comprehensive management of HF.