Yanli Chen, Qingrong Zeng, Qiwen Xia, Kaiquan Wang, Huan Mou, Rui Tang, Kui Ren, Jinhua Wang
E-cont is an early indicator of T2DM-related muscle decline. The combined model showed good diagnostic and differential performance across sarcopenia stages, with sex differences. The model serves as a noninvasive tool for risk stratification.
OBJECTIVE: To investigate the diagnostic and differential value of gastrocnemius shear wave elastography (SWE) combined with body mass index (BMI) in different stages of Type 2 diabetes mellitus (T2DM) related sarcopenia in elderly patients and to analyze sex differences.
METHODS: A total of 269 participants were classified into four groups according to the AWGS 2019: healthy controls (n = 62), those with T2DM without sarcopenia (n = 68), those with T2DM with possible sarcopenia (n = 64), and those with T2DM with sarcopenia (n = 75). SWE was used to measure the elastic modulus of the dominant-side gastrocnemius under relaxed (E-rest) and contracted (E-cont) conditions. Logistic regression was used to construct prediction models for total and sex-stratified populations, which were evaluated in three scenarios: core diagnosis, early risk identification, and differential factor analysis.
RESULTS: The patients with T2DM in the sarcopenia group were the oldest, had the longest diabetes duration, and had the lowest BMI, ASMI, handgrip strength, and E-cont; conversely, E-rest did not show significant intergroup differences. Lower E-cont and lower BMI were independent risk factors. The combined model showed excellent performance in the core diagnosis scenario (AUC 0.988; sensitivity 92.0%; specificity 95.4%), and the sex-stratified models also demonstrated strong performance (AUC 0.984 for males and 0.991 for females). The protective effect of E-cont was stronger in females (OR 0.710) than in males (OR 0.806), whereas the protective effect of BMI was stronger in males (OR 0.358) than in females (OR 0.388). The AUCs were 0.954 for early risk identification and 0.966 for differential factor analysis. The T2DM with possible sarcopenia group exhibited a low E-cont/high BMI pattern, whereas the T2DM with sarcopenia group exhibited a low E-cont/low BMI pattern.
CONCLUSION: E-cont is an early indicator of T2DM-related muscle decline. The combined model showed good diagnostic and differential performance across sarcopenia stages, with sex differences. The model serves as a noninvasive tool for risk stratification.