(SLB-063) Sex-Related Differences in the Risk of Rehospitalization among Heart Failure Patients in Korea

Background: Sex differences in heart failure (HF) may influence rehospitalization risk, as females more commonly present with HF with preserved ejection fraction, which may alter treatment response. While sex-related differences in HF prognosis have been reported, previous studies have shown conflicting results regarding the risk of rehospitalization, and evidence on this remains limited.

Objectives: To evaluate the sex-related differences in the risks of rehospitalization in HF patients in Korea

Methods: Using the National Health Insurance Service sample cohort database, we conducted a retrospective cohort study to compare the risk of rehospitalization for HF between males and females. Patients older than 18 years who were newly hospitalized for HF between January 1, 2010, and December 31, 2018, were included in the study. We applied a look-back period of three years to exclude patients with any prior HF-related hospitalization. Among these HF patients, males were matched to females in a 1:1 ratio based on baseline covariates including age, calendar time, medications at discharge, and baseline comorbidities using a propensity score derived from multivariate logistic regression analysis. The discharge date of the first hospitalization was defined as the start of follow-up, and patients were observed for one year thereafter. The outcome was rehospitalization due to HF, identified using ICD-10 codes (I50, I11, I130, I132). Fine and Gray models were used to compute the subdistribution hazard ratio (sHR) for rehospitalization according to sex, adjusting for baseline covariates and accounting for the competing risk of death.

Results: The study included 5,286 patients who were hospitalized for HF, comprising 2,451 males and 2,835 females. After propensity score matching, 2,031 patients were included in each sex group, and baseline characteristics were balanced between the groups. Among males, 254 patients were rehospitalized for HF within one year after discharge, with an incidence rate (IR) of 14.65 per 100 person-years, while among females 188 patients were rehospitalized, with an IR of 10.37 per 100 person-years. In the adjusted Fine and Gray model, males were significantly associated with a higher risk of rehospitalization compared to females (sHR: 1.43, 95% CI: 1.18–1.73).

Conclusions: In this study, males had a significantly higher risk of HF-related rehospitalization than females. These findings suggest that treatment strategies for HF should account for sex-specific risk factors, particularly in males, to reduce rehospitalization and improve long-term outcomes.