Fat infiltration in skeletal muscle (myosteatosis) may contribute to the development of insulin resistance and NAFLD.
The muscle fat and hepatic fat fraction can be measured reliably with chemical shift MRI.
Myosteatosis, muscle mass and muscle function were investigated in a well characterized NAFLD cohort.
Insulin resistance, not myosteatosis, was associated with the degree of hepatic steatosis and fibrosis.
Background and aim
Insulin resistance (IR) plays a central role in the complex pathophysiology of nonalcoholic fatty liver disease (NAFLD). IR is linked to fat infiltration in skeletal muscle (myosteatosis) and loss of skeletal muscle mass and function (sarcopenia). The clinical significance of myosteatosis in NAFLD is not well investigated. In this exploratory study we aimed to investigate the association between myosteatosis and NAFLD related hepatic and systemic variables in a well characterized NAFLD cohort.
We cross-sectionally studied forty-five NAFLD patients. The muscle fat fraction (MFF) was measured with chemical shift gradient echo MRI. In addition, the hepatic fat fraction (MRI), liver stiffness (FibroScan) and appendicular skeletal muscle mass (Dual-energy X-ray absorptiometry) were analyzed.
The median hepatic fat fraction was 15.64% (IQR 12.05–25.13) and significant (F2-F3) liver fibrosis (liver stiffness ≥7kPa) was diagnosed in 18 NAFLD patients (40%). MFF was not correlated with hepatic fat fraction (r=−0.035, P=0.823) and did not differ between subjects with or without significant fibrosis (P=0.980). No patient was diagnosed with sarcopenia based on the skeletal muscle mass index. In a linear regression model, anthropometric parameters, including body mass index (BMI) (P=0.018) and total body fat percentage (P=0.005), were positively associated with MFF while no association with insulin resistance (HOMA-IR) was observed.
Myosteatosis did not correlate with the degree of hepatic steatosis or fibrosis in this well characterized NAFLD cohort, but was positively correlated with total body fat percentage and BMI.Le texte complet de cet article est disponible en PDF.
Abbreviations : NAFLD, NASH, HCC, IR, IMCL, MFF, MRI, BMI, ASAT, ALAT, γ-GTP, ALP, HDL, LDL, CRP, HbA1C, HOMA-IR, FMI, SMI, DXA, LSM, ROI, IP, OP, SI
Keywords : Nonalcoholic fatty liver disease, Nonalcoholic steatohepatitis, Myosteatosis, Hepatic fibrosis, Sarcopenia, Body composition