Liver steatosis in juvenile obesity: correlations with lipid profile, hepatic biochemical parameters and glycemic and insulinemic responses to an oral glucose tolerance test

OBJECTIVE: The aim of this study was to evaluate liver steatosis in prepube rtal and pubertal obese and the correlations with the lipid profile, the se rum levels of hepatic parameters and the glycemic and insulinemic responses to an oral glucose tolerance test. SUBJECTS: 375 obese, 205 males and 170 females, Tanner pubertal stage I (n = 82), stages II-III (n = 80) and stages IV-V (n = 213). MEASUREMENTS: Body mass index (BMI), waist-hip ratio (WHR), total cholester ol and high density lipoprotein (HDL), cholesterol/HDL ratio, low density l ipoprotein (LDL), very low density lipoprotein (VLDL), triglycerides (TGL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gGT, gly cemia (G), insulinemia (IRI), fasting IRI/G ratio (FIGR), glycemic (mean bl ood glucose, MEG) and insulinemic (mean serum insulin, MSI) responses durin g a 120 min oral glucose tolerance test (OGTT), expressed as area under the curve (AUC)/120 min, pancreatic insulinemic response to glucose (IRG), and liver ultrasound scanning for assessing the degree of steatosis (moderate, severe). RESULTS: Liver steatosis was found in 33% of subjects in Tanner pubertal st age I, 36% in stage II-III and 47% in stages IV-V. BMI and transaminases we re correlated with the degree of steatosis in all pubertal stages. AST, ALT and gGT were higher in the presence of steatosis, while elevated TGL was p resent in late puberty only; however the increase of ALT is specific for st eatosis. CONCLUSION: Juvenile obesity involves a high risk of liver steatosis associ ated with alterations of transaminases and lipid but not glucose metabolism . These changes are apparent even to the prepubertal stage.