Sarcopenia index for detecting of the decreased muscle strength and mass in patients with the non-alcoholic fatty liver disease

Objective. To study the associations of the sarcopenia index with body composition parameters, strength, and skeletal muscle function in patients with non-alcoholic fatty liver disease. Materials and methods. The study included 130 patients with non-alcoholic fatty liver disease (NAFLD) who presented to the National Medical Research Center for Therapy and Preventive Medicine from February 2023 to December 2024. The diagnosis of sarcopenia was made based on measuring grip strength and skeletal muscle mass according to dual-energy X-ray absorptiometry data and assessing physical functioning. The serum cystatin C was measured using an enzyme-linked immunosorbent assay. Results. The median age of patients was 56.5 (47—64) years, and 58.5% were females (n=76). Thirty-eight (29.2%) NAFLD patients enrolled in the study had dynapenia, and 10 (7.7%) had sarcopenia. In patients with NAFLD and dynapenia or sarcopenia, the sarcopenia index values were significantly lower than in patients with NAFLD without dynapenia or sarcopenia (p=0.025 vs. p=0.037, respectively). In addition, the values of the sarcopenia index were significantly correlated with muscle strength and muscle function indicators (grip strength r=0.282; p=0.002; 4 meter gait speed r=–0.361; p<0.001). In accordance with the results of the ROC analysis, the values of the area under the ROC curve (AUROC) for the detection of a case of dynapenia or sarcopenia were 0.639 (p=0.025) and 0.663 (p=0.037), respectively, indicating the average quality of the model. Conclusion. The sarcopenia index is a promising surrogate marker of dynapenia and sarcopenia in patients with non-alcoholic fatty liver disease.