Background Sarcopenia is highly prevalent among patients undergoing hemodialysis and predicts mortality. In November 2025, the Asian Working Group for Sarcopenia updated its diagnostic criteria (AWGS 2025), excluding physical performance; its prognostic significance remains unclear. Therefore, this study evaluated the association between AWGS 2025-defined sarcopenia and all-cause mortality in patients undergoing hemodialysis, and compared its predictive performance with that of the AWGS 2019 criteria. Methods This multicenter retrospective cohort study screened 613 outpatients aged ≥ 65 years undergoing hemodialysis. Sarcopenia was classified under the AWGS 2025 and AWGS 2019 criteria. The primary outcome was all-cause mortality. Associations were assessed using adjusted Cox proportional-hazard models. Predictive accuracy was assessed using the C-index. Results A total of 403 patients were included in the final analysis. Under the AWGS 2025 criteria, the prevalence of sarcopenia and possible sarcopenia was 28.5% and 38.5%, respectively. Over a mean follow-up of 901 days, 97 patients (24.1%) died. Both sarcopenia and possible sarcopenia were significantly associated with increased mortality (hazard ratio [HR], 2.29; 95% confidence interval [CI], 1.20–4.36; HR, 1.97; 95% CI, 1.08–3.58, respectively). The C-index was comparable between models incorporating the AWGS 2025 and AWGS 2019 criteria (0.710 vs. 0.708). Conclusions AWGS 2025-defined possible sarcopenia and sarcopenia were significantly associated with mortality among patients undergoing hemodialysis, with prognostic performance comparable to the AWGS 2019 criteria despite excluding physical performance. Nevertheless, low physical performance remained an independent predictor of mortality and warrants continued clinical assessment. These findings support the validity of the AWGS 2025 criteria.
