Association between glycolipid metabolism 7 factors (GLM7) and sarcopenia: insights from NHANES and CHARLS

BACKGROUND: Sarcopenia is an age-related condition associated with metabolic dysfunction. The composite Glycolipid Metabolism 7 (GLM7) index may help quantify this association. AIM: To investigate association between the GLM7 and sarcopenia risk among middle-aged and older adults, and the predictive capability of GLM7. METHODS: This cross-sectional study analyzed data from the US National Health and Nutrition Examination Survey (NHANES 2011-2018, n = 1,563). Survey-weighted multivariable logistic regression models were employed to assess the association, and restricted cubic splines (RCS) analysis was conducted to examine the dose-response relationship between GLM7 and the risk of sarcopenia. Sensitivity analyses included subgroup analysis, further medication adjustment and complete-case analysis. Predictive performance of GLM7 was evaluated using area under the receiver operating characteristic curve (AUC), and was validated in the China Health and Retirement Longitudinal Study (CHARLS, n = 7,387). RESULTS: In NHANES, increase in GLM7 level was associated with higher odds of sarcopenia (fully-adjusted OR = 2.119, 95% CI: 1.319-3.406). A significant positive trend was observed across GLM7 quartiles (P for trend < 0.001). The association remained robust in sensitivity analyses and was significantly modified by sex (P for interaction < 0.001). The GLM7 index showed moderate predictive value in NHANES (test AUC = 0.756) and excellent performance in CHARLS (test AUC = 0.841). CONCLUSION: The GLM7 index is significantly associated with sarcopenia risk and demonstrates consistent predictive ability across diverse populations, suggesting its potential utility for risk screening.