Height- and Body Mass Index-Based Sarcopenia　― Prognostic and Functional Implications in Older Patients Hospitalized for Heart Failure ―

BACKGROUND: The 2025 Asian Working Group for Sarcopenia (AWGS) updated diagnostic criteria redefine sarcopenia based on low muscle strength and low skeletal muscle mass, incorporating body mass index (BMI)-adjusted appendicular skeletal muscle mass (ASM) alongside height-adjusted ASM. The clinical relevance of these definitions in heart failure (HF) patients remains unclear. METHODS AND RESULTS: This retrospective study included 594 patients aged ≥65 years hospitalized for HF (2016-2024). Sarcopenia was defined according to AWGS 2025 criteria as H-sarcopenia (height-adjusted ASM) or B-sarcopenia (BMI-adjusted ASM). The primary outcome was all-cause mortality. Physical function was assessed using gait speed. We analyzed associations using Cox proportional hazards and linear regression models. The prevalence of H-sarcopenia and B-sarcopenia was similar (24.2% vs. 25.1%, respectively), but BMI-dependent patterns differed, with the prevalence of H-sarcopenia decreasing and B-sarcopenia increasing as BMI increased. H-sarcopenia was independently associated with higher mortality (adjusted hazard ratio 1.48; 95% confidence interval 1.04-2.12), although its prognostic impact was attenuated at higher BMI. B-sarcopenia was not associated with mortality. Both sarcopenia definitions were associated with slower gait speed (P<0.001), but B-sarcopenia showed superior model performance (P<0.001 for the difference in root mean square error). CONCLUSIONS: In patients hospitalized with HF, H-sarcopenia and B-sarcopenia had distinct prognostic and functional implications: H-sarcopenia was related to mortality, particularly for lower BMI, whereas B-sarcopenia better reflected physical function, supporting outcome-specific sarcopenia definitions.