Insulin Resistance but Not Visceral Adiposity Index Is Associated with Liver Fibrosis in Nondiabetic Subjects with Nonalcoholic Fatty Liver Disease.

Abstract

Nonalcoholic fatty liver disease (NAFLD) is associated with obesity, type 2 diabetes mellitus, and dyslipidemia. It is well known that the presence of visceral fat increases the risk for metabolic complications of obesity, especially NAFLD. The visceral adiposity index (VAI), a novel marker of visceral fat dysfunction, shows a strong association with insulin resistance and also cardiovascular and cerebrovascular events. However, there is conflicting data regarding the association between VAI and NAFLD. Our aim was to assess the relationship between VAI, insulin resistance, adipocytokines, and liver histology, in nondiabetic subjects with NAFLD. A total of 215 male patients with biopsy-proven NAFLD were included. Among this group, serum levels of adiponectin, tumor necrosis factor-α (TNF-α, interleukin-6 (IL-6), and high-sensitivity C-reactive protein (hsCRP) were measured in 101 patients whose blood samples were available. High gamma-glutamyl transferase (GGT), high total cholesterol (TC), high triglycerides (TGs), low high-density lipoprotein cholesterol (HDL-C), and presence of metabolic syndrome were significantly associated with higher VAI, although only higher GGT and TC were independent factors on multiple linear regression analysis. On the other hand, no significant association was found between VAI and adiponectin, TNF-α, IL-6, and hsCRP levels. The multivariate analysis of variables in patients with (n=124) and without (n=91) fibrosis showed that only higher homeostasis model assessment of insulin resistance value was independently associated with liver fibrosis. Our findings suggest that VAI is not related to the severity of hepatic inflammation or fibrosis in nondiabetic patients with NAFLD. The lack of association between the adipocytokines and VAI also implies that the VAI may not be a significant indictor of the adipocyte functions.