Nonalcoholic fatty liver disease and accelerated loss of skeletal muscle mass: A longitudinal cohort study

Abstract

Background and Aims Whether subjects with NAFLD are at increased risk of sarcopenia is not well established. Approach and Results This is a cohort study of 52,815 men and women of 20 years of age or older who underwent at least two health check‐up exams with bioelectrical impedance analysis and abdominal ultrasound imaging. Bioelectrical impedance analysis was used to calculate appendicular skeletal muscle mass (ASM). NAFLD was assessed by ultrasonography, and its severity was assessed by the NAFLD fibrosis score (NFS). We estimated the 5‐year change in ASM comparing participants with and without NAFLD at baseline using mixed linear models. The 5‐year change in ASM in participants without and with NAFLD was −225.2 g (95% CI −232.3, −218.0) and −281.3 g (95% CI −292.0, −270.6), respectively (p < 0.001). In multivariable adjusted analysis, the difference in 5‐year change in ASM comparing participants with and without NAFLD was −39.9 g (95% CI −53.1, −26.8). When participants with NAFLD were further divided by NAFLD severity, ASM loss was much faster in participants with NAFLD with intermediate to high NFS than in those with low NFS. Conclusions Participants with NAFLD were at increased risk of sarcopenia, indicated by faster loss of skeletal muscle mass. Patients with NAFLD may need screening and early intervention to mitigate skeletal muscle mass loss.

Reply

“…We thank Dr. Zhang et al [ 1 ] for their interest in our study. [ 2 ] We agree that our study is not sufficient to prove a causal effect of NAFLD on sarcopenia. Participants with and without NAFLD were very different, and multivariate adjustment might not be enough to completely remove confounding.…”

Interaction between sarcopenia and nonalcoholic fatty liver disease

“…When stratified by fibrosis severity, skeletal muscle mass loss was faster in NAFLD subjects with an intermediate-to-high probability of advanced fibrosis than in those without (Table 2). 108 Muscle quality also plays a critical role in the development of NASH. Myosteatosis determines muscle strength and function, and metabolic and liver-related clinical outcomes.…”

Management of NAFLD in primary care settings

“…13 Sarcopenia is another risk factor for NAFLD, which is in turn associated with the progression of sarcopenia. 14,15 This is the basis of the beneficial effect of both aerobic exercise and resistance training.…”

“…One of the studied mechanisms is the overactivation of the endocannabinoid system, which is related to various metabolic disorders and associated comorbidities 13 . Sarcopenia is another risk factor for NAFLD, which is in turn associated with the progression of sarcopenia 14,15 . This is the basis of the beneficial effect of both aerobic exercise and resistance training.…”