Association of muscle mass, grip strength and fat-to-muscle ratio and metabolic dysfunction-associated steatotic liver disease in a middle-to-elderly aged population

The association of appendicular skeletal muscle mass (ASM), grip strength and fat-to-muscle ratio (FMR) and the progression of metabolic dysfunction-associated steatotic liver disease (MASLD) are not well known. This study included participants older than 40 years who underwent bioelectrical impedance assessment in Prevalence of Metabolic Diseases and Risk Factors in Shunde (SPEED-Shunde). We measured grip strength with an electronic grip strength metre. ASM and grip strength were adjusted by dividing body mass index (BMI). FMR was calculated as total fat mass to total muscle mass. Liver steatosis and liver fibrosis were evaluated by vibration-controlled transient elastography. Multifactorial logistic regression was used to analyse the relationship between ASM, grip strength, FMR, and MASLD or MASLD-associated liver fibrosis. We performed subgroup analyses according to sex, age and BMI. Interaction tests and linear trend tests were also conducted. This study included a total of 3277 participants. FMR was positively associated with MASLD (OR: 1.89, 95% CI: 1.66–2.15) and MASLD-associated liver fibrosis (OR: 1.70, 95% CI: 1.22–2.37). While ASM/BMI (OR: 0.59, 95% CI: 0.52–0.67) or grip strength/BMI (OR: 0.72, 95% CI: 0.66–0.78) were negatively associated with MASLD. Interactions were observed between ASM/BMI and age, grip strength and sex in MASLD, as well as FMR and MASLD-associated liver fibrosis. In a middle-to-elderly aged population, FMR was positively associated with the risk of MASLD and MASLD-associated liver fibrosis, and muscle mass and grip strength were negatively associated with MASLD, rather than MASLD-associated liver fibrosis.