Association of weight change and in‐hospital mortality in patients with repeated hospitalization for heart failure

Background Although weight loss in heart failure (HF) is a detrimental condition known as cachexia, weight gain caused by fluid retention should also be considered harmful. However, studies with sufficient number of patients examining the impact of weight change and its interval on in‐hospital mortality in HF have not been conducted thus far. We sought to elucidate the association of weight change with in‐hospital mortality in patients with HF. Methods This retrospective observational study used data from the Diagnosis Procedure Combination database, a nationwide inpatient health claims database in Japan. In total, 48 234 patients repeatedly hospitalized for HF (median 82 [74–87] years; 46.4% men) between 2010 and 2018 were included. Weight change was derived from body weight at the first and second admissions. Results The median weight change and interval between two hospitalizations were −3.1 [−8.3 to −1.8] % and 172 [67–420] days, with 66.9% of overall cohort experiencing any weight loss. As a result of multivariable‐adjusted logistic regression analysis, weight loss +5.0% were associated with increased in‐hospital mortality (adjusted odds ratio [OR] [95% confidence interval]: 1.46 [1.31–1.62], P