Usefulness of Triglyceride to High-Density Lipoprotein Ratio and Alanine Aminotransferase for Predicting Insulin Resistance and Metabolic Syndrome in the Japanese Population.

Abstract

Background: Considering the fact that both alanine aminotransferase (ALT) and the triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C) ratio are useful markers for cardiovascular disease, insulin resistance (IR), and metabolic syndrome (MetS), the possible association of ALT and TG/HDL-C ratio is conceivable, but the association is not well studied. Moreover, assessment of IR and MetS by a combination lipid and liver biomarkers has rarely been carried out. Methods: A total of 11,808 Japanese subjects who underwent an annual health examination and who were not taking medications were recruited. The association between TG/HDL-C ratio and ALT level was investigated using correlation and multiple linear regression analyses. Homeostasis model assessment of insulin resistance (HOMA-IR) and the number of MetS components were evaluated after subjects were stratified by TG/HDL-C ratio and ALT levels. Results: Correlation analysis revealed that ALT levels were positively associated with TG/HDL-C ratio. Moreover, multiple linear regression analysis revealed that TG/HDL-C ratio was positively associated with ALT levels, and the association was attenuated but persisted in both men and women after additional adjustment for visceral adiposity (body mass index, waist circumference, or fatty liver) and IR (HOMA-IR). HOMA-IR and MetS component number increased with either ALT or TG/HDL-C ratio in both men and women. HOMA-IR and MetS component number were particularly high (HOMA-IR: men 2.82, women 3.22, MetS component number: men 2.6, women 2.1) in subjects with highest ALT level and TG/HDL-C ratio. Conclusions: TG/HDL-C ratio showed a positive association with ALT levels in both sexes. Assessments of IR and MetS can become more precise by evaluating TG/HDL-C ratio and ALT, simultaneously.