Body roundness index as a predictor of 3-month readmission in elderly patients with first-episode acute heart failure.

AIMS: To determine whether admission body roundness index (BRI), a validated anthropometric metric of central adiposity, independently predicts 3-month all-cause readmission and rehospitalization for acute heart failure (AHF) in elderly patients hospitalized for a first AHF episode.

METHODS

In this single-center retrospective cohort study, 317 patients aged >60 years with a first AHF hospitalization were enrolled and stratified by BRI tertiles. The endpoints were all-cause readmission and AHF rehospitalization within 3 months. Patients who died during follow-up were retained in the cohort and censored at the time of death, and associations were analyzed using the cause-specific Cox proportional hazards model. Associations were assessed using multivariable Cox regression, restricted cubic spline analysis, and pre-specified subgroup analyses.

RESULTS

During follow-up, 3 patients (0.95%) died (1 in each tertile at 9, 22, and 45 days) and were censored at the time of death, and 128 patients (40.76%) experienced all-cause readmission and 68 (21.73%) were rehospitalized for AHF. After full adjustment, each 1-unit increment in BRI was associated with a 48% higher risk of all-cause readmission (HR 1.48, 95% CI 1.20-1.83) and a 2.15-fold risk of AHF rehospitalization (HR 2.15, 95% CI 1.55-2.98); risks in the highest tertile significantly exceeded those in the lowest tertile. Restricted cubic spline analysis unmasked striking nonlinear threshold effects: all-cause readmission risk escalated sharply when BRI surpassed 5.40 (HR 2.75, 95% CI 1.98-3.82), whereas AHF rehospitalization risk surged beyond a BRI of 7.05 (HR 2.93, 95% CI 1.34-6.40). Notably, the middle BRI tertile exhibited a markedly lower all-cause readmission risk relative to the lowest tertile (HR 0.38, 95% CI 0.17-0.87), whereas AHF rehospitalization risk did not differ. This divergent pattern mechanistically reconciles the "obesity paradox" by distinguishing a sarcopenic phenotype in the lowest-BRI group from a high-adiposity phenotype in the upper extreme. The direction of association remained consistent across all subgroups, with significant effect modification by smoking status, marital status, NYHA class, and diabetes.

CONCLUSION

Admission BRI is an independent predictor of 3-month all-cause readmission and AHF rehospitalization in elderly patients with AHF, and may serve as a simple, low-cost tool for early post-discharge risk stratification in this population.