Association between Estimated Glucose Disposal Rate and Sarcopenia in US Adults: A Cross-Sectional Study Based on NHANES 2011–2018

Background Sarcopenia is an age-related disorder that severely impacts the quality of life and health of older adults, primarily characterized by accelerated loss of muscle mass and strength. Insulin resistance represents a key pathophysiological mechanism underlying sarcopenia. The estimated glucose disposal rate (eGDR) is a novel indicator of insulin resistance that reflects the body's ability to process glucose. It is unclear about the association between eGDR and sarcopenia in adults. This research investigates the relationship between eGDR and sarcopenia to support improved clinical identification of the condition. Methods This research analyzed data from the 2011–2018 National Health and Nutrition Examination Survey (NHANES), which included 7,147 participants. eGDR was determined based on the following formula: eGDR (mg/kg/min) = 21.158 − (0.09 × WC) − (3.407 × hypertension) − (0.551 × HbA1c), [WC (cm), hypertension (yes = 1/no = 0), and HbA1c (%)]. Based on eGDR values, participants were sorted into quartiles. The connection between eGDR and sarcopenia risk was analyzed through multivariable logistic regression models. Dose-response association were analyzed via the restricted cubic spline (RCS) curves. Subgroup analyses and interaction tests were conducted to assess the robustness of the association. Mediation analysis was used to assess the mediating role of inflammation in the relation between eGDR and sarcopenia. Results Multivariable logistic regression revealed an obvious inverse association between eGDR and sarcopenia. In the fully adjusted model, compared with the lowest eGDR quartile group, the adjusted odds ratios (95% confidence intervals) for sarcopenia in quartiles 2 to 4 were 0.48 (95% CI: 0.32, 0.71; p < 0.001), 0.22 (95% CI: 0.13, 0.37; p < 0.001), and 0.07 (95% CI: 0.04, 0.13; p < 0.001), respectively. The results of subgroup analyses and interaction tests indicate that this relation is not affected by factors such as age, gender, race, marital status, education, smoking, or drinking. Mediation analysis confirmed the mediating roles of inflammatory indexes in the association between eGDR and sarcopenia (p < 0.001). Conclusion A negative relation was observed between eGDR and the prevalence of sarcopenia. Inflammatory response may mediate this relationship. eGDR may serve as a potential biomarker for the early identification and diagnosis of sarcopenia.