Prediction of sarcopenia onset in type 2 diabetes using urinary titin levels: A Japanese prospective cohort study

Objective Predictive power of urinary titin for incident sarcopenia was studied in Japanese individuals with type 2 diabetes. Research Design and Methods Baseline urinary titin levels were measured, and sarcopenia was evaluated annually using the AWGS 2019 criteria. Kaplan-Meier curves, Cox models, and time-dependent receiver operating characteristic analyses were employed to assess incident sarcopenia. Results Among 444 participants (median follow-up: 1078 days), 41 developed sarcopenia. The high titin tertile was associated with an elevated sarcopenia risk (log-rank P=0.04). Cox models associated titin with sarcopenia (adjusted hazard ratio per SD: 1.37, 95% CI: 1.05–1.77, P=0.019) and low muscle strength. Risk estimates were consistent across subgroups, including those aged ≥70 years, males, individuals with BMI<25 kg/m2, HbA1c ≥7%, and eGFR ≥60 mL/min/1.73 m2 (P for interaction >0.05). Conclusions Elevated urinary titin levels predict sarcopenia and low muscle strength in individuals with type 2 diabetes, supporting its use as a noninvasive biomarker.