Obesity, insulin resistance and their interaction on liver enzymes

INTRODUCTION: To investigate weight status, insulin resistance assessed by HOMA-IR, and their interaction on liver function in non-diabetic Chinese adults. METHODS AND RESULTS: A total of 7066 subjects were included, and divided into normal weight (n = 3447), overweight (n = 2801), and obese (n = 818) groups. Data including weight, height, waist circumference, fasting blood glucose, fasting insulin, total cholesterol, triglycerides, y-glutamyl transferase (GGT), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were acquired. In multi-linear regression analysis for liver enzymes as dependent variables, insulin resistance emerged as a determinant of ALT (β = 0.165, P<0.001), AST (β = 0.040, P<0.001) and GGT (β = 0.170, P<0.001) after adjusting for age, sex, body mass index, triglyceride, and cholesterol. Interactions between insulin resistance and weight status by body mass index were observed in ALT (P<0.001), AST (P<0.001) and GGT (P = 0.0418). CONCLUSION: Insulin resistance had significant associations with greater risk of elevated ALT, AST and GGT level in non-diabetic Chinese adults, especially among those who were overweight/ obese.