Should nonalcoholic fatty liver disease be included in the definition of metabolic syndrome? A cross-sectional comparison with Adult Treatment Panel III criteria in nonobese nondiabetic subjects.

Description

In this study, Musso et al. tested the hypothesis that non-alcoholic fatty liver disease (NAFLD) might be more closely associated with insulin resistance (evaluated with HOMA-IR index) than current National Cholesterol Education Program-Adult Treatment Panel III (NCEP-ATP III) clinical criteria in nonobese subjects without diabetes. They also verified the hypothesis that fatty liver increases cardiovascular risk in otherwise healthy insulin-resistant individuals, independent of insulin resistance, the metabolic syndrome, and circulating adipokines (tumor necrosis factor-a (TNF-a), leptin, adiponectin, resistin). The authors found that fatty liver, as diagnosed by alanine aminotransferase (ALT) levels and ultrasonography, was more closely associated with insulin resistance than with NCEP-ATP III clinical criteria. Moreover, the presence of NAFLD in insulin-resistant subjects was more strongly associated with insulin resistance and with markers of oxidative stress and endothelial dysfunction, independently of the metabolic syndrome, adiposity, and adipokines. These findings suggest that NAFLD may be an early marker of endothelial dysfunction, independently of insulin resistance and of traditional risk factors, and might facilitate the identification of those at increased cardiometabolic risk among nonobese individuals without diabetes.