The impact of fat distribution on the severity of nonalcoholic fatty liver disease and metabolic syndrome

The patterns of fat distribution and their relationship to severity of nonalcoholic fatty liver disease (NAFLD) are unknown. The objectives of this study were to define the fat distribution patterns and their relationship to histological severity and metabolic parameters in subjects with NAFLD. Anthropometric indices and total body fat were measured in 123 subjects. Fat distribution patterns were defined as: general, abdominal, limb, truncal, and dorsocervical lipohypertrophy (DCL) a novel finding in NAFLD. Eighty-one (66%) of the subjects were obese, and 94 (76%) had abdominal obesity. Thirty-five (28.5%) had DCL. Whereas body mass index (BMI) correlated best with the presence of diabetes (r = 0.22, P < 0.05), waist circumference (WC) correlated best with hypertension (r = 0.2, P < 0.05), hypertriglyceridemia (r = 0.37, P < 0.001), and insulin resistance (homeostasis model of assessment for insulin resistance [r = 0.68, P < 0.0001]). None of the patterns of fat distribution were significantly associated with severity of hepatic steatosis. Abdominal obesity (WC) correlated with inflammation (r = 0.2, P < 0.05) only. DCL correlated significantly with the severity of all histological parameters except steatosis. Whereas DCL was the single greatest contributor to the variability in severity of histological parameters, a model combining BMI, WC, and DCL showed the greatest contribution to the variability in severity of individual histological parameters. The addition of steatosis grade to the model significantly increased its contribution to the range of lobular inflammation. Conclusion: WC predicts metabolic risk profile with the most significance. However, DCL is most strongly associated with severity of steatohepatitis. WC and BMI added modestly to the contribution of DCL to severity of nonalcoholic steatohepatitis.