Non-alcoholic fatty liver disease in young adult severely obese non-diabetic patients in South Italy

Abstract

Background/aims: In the absence of other causes, obesity increases the risk of liver disease. We evaluated the prevalence and degree of metabolic and hepatic abnormalities associated with non-alcoholic fatty liver disease (NAFLD) in type II-III obesity in a metropolitan area of South Italy.

Methods: 187 (81 M, 106 F) young adult non-diabetic obese patients, age range 18-50 years (mean 31.9 +/- 8.8), body mass index (BMI) > or =30 (mean 47.5 +/- 9.6), consecutively admitted from January 2000 to April 2003 to the Obesity Outpatients Clinic entered into the study. Patients were divided into two groups: (1) BMI 30.0-39.9, and (2) BMI> or =40. Ultrasound detected liver steatosis was classified as: (I) mild; (II) moderate, and (III) severe.

Results: All patients, except 4, showed a variable degree of steatosis: mild was more frequent among females, severe steatosis present only in grade III obesity, with higher prevalence in males than in females (p < 0.001). Mean serum transaminases, in particular alanine aminotransferase (ALT), increased according to BMI and degree of steatosis. Homeostasis Model Assessment (HOMA) index, ferritin and fibrinogen levels increased with BMI, particularly in severe steatosis. In group 2, patients with BMI> or =40 showed a positive correlation between ferritin, aspartate aminotransferase (AST) (r = 0.46, p < 0.018), ALT (r = 0.41, p < 0.036) and gamma-glutamyltransferase (gammaGT) (r = 0.51, p < 0.007), between serum triglycerides (TG) and AST (r = 0.28, p < 0.036), ALT (r = 0.30, p < 0.02) and between HOMA and ALT (r = 0.30, p < 0.03) and gammaGT (r = 0.35, p < 0.012). In group 2 patients with severe steatosis the prevalence of metabolic syndrome according to Adult Treatment Panel III (ATP III) was 40%.

Conclusion: These data suggest that, in young adult non-diabetic grade III obese patients, fatty liver is always present and strictly related to insulin resistance which, in the presence of severe liver steatosis, is also related to serum ferritin.