Relationship between Muscle Mass/Strength and Hepatic Fat Content in Post-Menopausal Women

Background and Objectives: Recent studies have shown that low skeletal muscle mass can contribute to non-alcoholic fatty liver disease through insulin resistance. However, the association between muscle mass/strength and hepatic fat content remains unclear in postmenopausal women. Methods: In this study, we assessed the associations between muscle mass/strength and various severities of non-alcoholic fatty liver disease. Using single-voxel proton magnetic resonance spectroscopy, 96 postmenopausal women between the ages of 50 and 65 were divided into four groups (G0-G3) by hepatic fat content: G0 (hepatic fat content <5%, n = 20), G1 (5% ≤ hepatic fat content < 10%, n = 27), G2 (10% ≤ hepatic fat content < 25%, n = 31), and G3 (hepatic fat content ≥25%, n = 18). Muscle mass indexes were estimated as skeletal muscle index (SMI)% (total lean mass/weight × 100) and appendicular skeletal muscular mass index (ASM)% (appendicular lean mass/weight × 100) by dual energy X-ray absorptiometry. Maximal isometric voluntary contraction of the handgrip, elbow flexors, and knee extensors was measured using an adjustable dynamometer chair. Fasting plasma glucose, insulin, and follicle-stimulating hormones were assessed in venous blood samples. Results: The results showed negative correlations between hepatic fat content and SMI% (r = -0.42, p < 0.001), ASM% (r = -0.29, p = 0.005), maximal voluntary force of grip (r = -0.22, p = 0.037), and knee extensors (r = -0.22, p = 0.032). Conclusions: These significant correlations almost remained unchanged even after controlling for insulin resistance. In conclusion, negative correlations exist between muscle mass/strength and the progressed severity of non-alcoholic fatty liver disease among post-menopausal women, and the correlations are independent of insulin resistance.