Muscle fat content linked to nonalcoholic steatohepatitis

Muscle fat content shares a strong correlation with nonalcoholic steatohepatitis (NASH) in patients with obesity, a recent study has found. Muscle mass, on the other hand, has no such effect.

“Muscle fat content is strongly associated with NASH and decreases upon NASH improvement. These data indicate that muscle fatty infiltration could be a marker and possible pathophysiological contributor to NASH,” the researchers said.

The study included 184 patients (mean age 41±6 years, 70.6 percent women), of whom 150 had nonalcoholic fatty liver disease (NAFLD). Muscle mass was significantly higher in patients with vs without NAFLD (p<0.0001). On the other hand, NASH was not associated with sarcopoenia.

Mean skeletal muscle fat index (SMFI) was higher in patients with ≥F2 and F0–F1 NASH vs those with NAFLD (78.5±23.6 and 73.1±15.6 vs 61.2±12.6, respectively; p<0.001). Moreover, a 1-point increment in any of the individual NASH features (such as steatosis, ballooning, or inflammation) correlated with significant increases in SMFI (p<0.05 for all).

Adjustments for multiple confounders did not attenuate the interaction between SMFI and NASH (p<0.025 for all).

Following after either dietary or surgical intervention, 75 percent of participants showed improvements in NASH (NAFLD activity score <3 or a 2-point reduction in score). Notably, such improvements correlated with a significant decrease in SMFI (p<0.001). All patients who saw a ≥11-percent drop in SMFI also achieved the criteria for NASH improvement.