Fasting insulin and uric acid levels but not indices of iron metabolism are independent predictors of non-alcoholic fatty liver disease. A case-control study.

BACKGROUND: Non-alcoholic fatty liver disease is a common reason for hepatological consultation and may herald severe hepatic and extra-hepatic disease. The aetiopathogenesis of this condition is an area of increasing interest. AIM: To evaluate anthropometric and biochemical factors associated to non-alcoholic fatty liver disease in a case-control study. Methods. Demographic and biochemical data of 60 consecutive patients with bright liver absent-to-low alcohol consumption, no evidence of viral, genetic and autoimmune diseases, were compared to those of 60 age- and gender-matched historical controls without fatty liver by univariate and multiple logistic regression analysis.
RESULTS: Patients were more often hypertriglyceridaemic, obese and diabetic than controls (p<.01). Mean values of alanine transaminase, gammaglutamyltranspeptidase, triglycerides, uric acid, fasting and log insulin, transferrin percent saturation and ferritin were significantly higher in the patients, while transferrin and quantitative insulin sensitivity check index, a quantitative insulin sensitivity index, were lower. No iron storage was found in those who underwent liver biopsy At univariate analysis the relative risk for non-alcoholic fatty liver disease significantly increased (p<0. 05) with increasing body mass index, fasting insulin, alanine transaminase, uric acid, triglycerides and gammaglutamyltranspeptidase; it decreased with increasing transferrin and quantitative insulin sensitivity check index. Multiple logistic regression analysis disclosed only fasting insulin and uric acid to be independent predictors of non-alcoholic fatty liver disease (p<0.05).
CONCLUSIONS: Fasting insulin and serum uric acid levels indicating insulin resistance, but not indices of iron overload, are independent predictors of non-alcoholic fatty liver disease.