Significant correlation between insulin resistance and serum gamma-glutamyl transpeptidase (γ-GTP) activity in non-drinkers

To understand the significance of elevated serum γ-GTP levels, factors relevant to the serum γ-GTP level were studied using data of health check-ups for the employees of a Japanese corporation. The γ-GTP level was positively correlated with levels of various liver function tests including aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Except for them, the γ-GTP level was positively correlated with levels of insulin resistance, uric acid, total cholesterol, triglyceride, and body mass index. The correlation between the γ-GTP level and LDL cholesterol was also observed only when subjects who drank more than 5 times a week were selectively studied. When non-drinkers and opportunity drinkers were selectively studied, 63.6% of subjects whose γ-GTP level was more than 120 IU/liter showed elevated insulin resistance levels. Multiple factors including insulin resistance may affect serum γ-GTP activity in clinical subjects.