A cohort follow-up study of the relationship between serum liver enzymes and the incidence of impaired glucose tolerance in middle-aged and elderly Chinese people / 中华内分泌代谢杂志

ABSTRACT

Objective To study the relationship between liver enzymes [ alanine transaminase ( ALT), gamma-glutamyltransferase ( GGT), aspartate amino transferase ( AST)] and the incidence of impaired glucose tolerance(IGT) in middle-aged and elderly people. Methods A group of middle-aged and elderly residents who participated in the REACTION study in 2011 from Guiyang community were enrolled in our study. Of which, a total of 4228 participants with normal blood glucose detected by oral glucose tolerance test (OGTT) and serum ALT levels were investigated as baseline population. The baseline survey included questionnaire survey and physical examination (height, weight, waist circumference, blood pressure, etc. ), and the serum ALT, AST, GGT, total cholesterol ( TC ), triglyceride ( TG ), high density lipoprotein-cholesterol ( HDL-C ), low density lipoprotein-cholesterol (LDL-C), fasting blood glucose, postprandial 2h plasma glucose(2hPG) in OGTT, and fasting insulin(FINS) were tested. After 3 years of follow-up, all subjects received quartile grouping according to the basal liver enzyme levels, and the incidence of IGT was respectively calculated. One-way analysis of variance was used to compare the differences of basal liver enzyme levels between IGT and normal blood glucose groups. The risk of IGT based on quartile grouping was assessed by multivariate regression analysis, and the odds ratios (ORs) were estimated by the logistic regression model. Results After eliminating the 35 died patients, 3188 participants were followed over 3 years. Among them, 2400 subjects revealed normal blood glucose level, 61 developed into type 2 diabetes mellitus(T2DM), 91 developed into IFG, and 636 developed into IGT. The incidence of IGT increased along with the elevation of serum ALT level (P<0. 01). After adjusting the risk factors including body mass index, regular smoking, regular drinking, regular exercise, family history of diabetes,homeostasis model assessment for insulin resistant index(HOMA-IR), post-load 2h blood glucose, and GGT, the results manifested that patients in high basal ALT level group had 1. 462-fold chance of susceptibility in developing IGT compared with that in the low level group, with 95％ CI of 1. 129 to 1. 891. The analysis based on gender showed that the incidence of IGT was associated with basal ALT level in the female group. The OR value was estimated to be 1. 481(95％ CI 1. 107-1. 981) in high basal ALT level group as compared with the low level group. Basal serum GGT and AST levels were not associated with the incidence of IGT. Conclusion Even an elevated level of ALT within normal reference range also tends to be a risk factor for IGT in middle-aged and elderly women.