Clinical Implications of the AWGS 2025 Sarcopenia Criteria in a Large Cohort of Community-Dwelling Thai Older Adults.

BACKGROUND: The Asian Working Group for Sarcopenia (AWGS) 2025 criteria introduced revised age-specific cutoffs and appendicular skeletal muscle mass adjusted for body mass index (ASM/BMI) as an alternative muscle mass index. We evaluated their effects on sarcopenia classification among Thai older adults. METHODS: This cross-sectional study included 8,073 community-dwelling adults aged ≥60 years attending a tertiary geriatric outpatient clinic. Low muscle mass and sarcopenia were classified using AWGS 2019 and 2025. Discordant ASM/height²- and ASM/BMI-based phenotypes were characterized, and age- and sex-adjusted associations with handgrip strength and gait speed were examined. RESULTS: Low muscle mass prevalence increased from 43.2% under AWGS 2019 to 44.6% after applying the revised AWGS 2025 ASM/height² cutoffs and to 51.4% after including ASM/BMI. Sarcopenia prevalence increased from 15.1% to 17.5% and 19.7%, respectively. ASM/BMI identified 547 additional participants with low muscle mass. Participants with isolated low ASM/BMI had greater overall and central adiposity than those with isolated low ASM/height². ASM/height² was positively associated with handgrip strength (standardized β=0.262, p<0.001), whereas ASM/BMI was positively associated with gait speed (standardized β=0.122, p<0.001). Neither index was consistently superior across outcomes. CONCLUSION: AWGS 2025 broadened low muscle mass and sarcopenia classification through revised age-specific cutoffs and ASM/BMI, which identified a complementary adiposity-related phenotype.