Diabetes is the strongest risk factor of hepatic fibrosis in lean patients with non-alcoholic fatty liver disease

Abstract

We read the commentary by Francque and Wong1 with great interest. They pointed out that metabolic dysfunction could be the main factor associated with an increased risk of hepatic fibrosis among lean patients with non-alcoholic fatty liver disease (NAFLD). However, it is unclear whether the definition of metabolic dysfunction would also fit lean patients, who are less likely to have metabolic risks.2 Herein, we evaluated the fibrosis burden in lean patients with NAFLD according to the presence of each metabolic dysfunction component.

We analysed participants in a community-based cohort, all of whom have undergone magnetic resonance elastography (MRE) for their health check-up (N=6775, 100% single ethnic Korean). Fatty liver was diagnosed by ultrasonography. The prevalence of NAFLD and lean (body mass index <23) NAFLD in all subjects was 35.2% and 3.7%, respectively. The mean liver stiffness value was lower in lean patients with NAFLD than in non-lean patients (2.26±0.55 vs 2.39±0.53, p<0.001) (online supplemental table 1). However, there was no difference in the prevalence of both significant (MRE ≥3.0 kPa) and advanced (MRE ≥3.6 kPa) fibrosis. Lean patients with NAFLD were older, more likely to be female, and had lower body mass index and waist circumference. In addition, lean patients with NAFLD showed lower alanine transaminase and triglyceride levels and higher high-density cholesterol levels than non-lean patients. Interestingly, the prevalence of metabolic syndrome was lower in lean patients with NAFLD than in non-lean patients (7.1% vs 30.6%, p<0.001), and the prevalence of diabetes (11% in lean NAFLD vs 12.9% in non-lean NAFLD, p=0.402) did not differ between the two groups.