Prevalence of Non-alcoholic Fatty Liver Disease and Steatohepatitis Risk Factors in Patients Undergoing Bariatric Surgery.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) associated with obesity comprises pathological changes ranging from steatosis to steatohepatitis; these can evolve to cirrhosis and hepatocellular carcinoma.

OBJECTIVES: The objectives of this study are to assess the prevalence of and predictive markers for steatohepatitis in obese patients undergoing bariatric surgery.

METHODS: A prospective study of 184 morbidly obese patients undergoing bariatric surgery formed the study cohort. Patients taking potentially hepatotoxic medications and those with viral diseases and a history of excessive alcohol consumption were excluded. Liver biopsies were performed during surgery with a "Trucut" needle. Patients were classified into the following groups according to the histopathological findings: normal, steatosis, mild steatohepatitis, and moderate-severe steatohepatitis. Factors associated with steatohepatitis were evaluated using logistic regression. p values <0.05 were considered significant.

RESULTS: The prevalence of NAFLD was 84 % (steatosis, 22.0 %; mild steatohepatitis, 30.8 %; moderate-severe steatohepatitis, 32.0 %). Independent predictive factors for steatohepatitis were age (odds ratio (OR), 1.05; 95 % confidence interval (CI), 1.01-1.09; p = 0.011), waist circumference (OR, 1.03; 95 % CI, 1.00-1.06; p = 0.021), serum alanine aminotransferase (ALT) levels (OR, 1.04; 95 % CI, 1.01-1.08; p = 0.005), and serum triglyceride levels (OR, 1.01; 95 % CI, 1.00-1.01; p = 0.042). Score values for each predictor were derived from regression coefficients and odds ratio, and a total (risk) score was obtained from the sum of the points to evaluate the probability of having steatohepatitis.

CONCLUSION: Age, waist circumference, serum ALT levels, and serum triglyceride levels are efficient and non-invasive predictive markers for the diagnosis and management of steatohepatitis in morbidly obese patients.