Exploring effective indicators for early detection of IGT

Impaired glucose tolerance (IGT) is an important state for early detection of type 2 diabetes, but it is quite difficult to identify by laboratory tests, except for the oral glucose tolerance test (OGTT). The purpose of this research was to explore effective indicators for IGT based on routine laboratory test items. The characteristic differences in each test item were analyzed among three groups, normal (N=3534), IGT (N=2239), and diabetes (N=3110), based on the OGTT values extracted from the medical records of Kochi Medical School hospital from 1981 to 2011. The multiple Wilcoxon´s signed rank sum test was used to test the average values of all test items for each patient within 30 days of the OGTT. Binomial logistic regression analysis was performed using the significantly different test items between the normal and IGT groups. The analyzed data were validated because the well-known test items (e.g., HbA1c, TG, CPR, gamma-GT, AST, and BUN) were significantly different (p<;0.05) between the normal and IGT groups. On the logistic regression analysis, there were significant differences in chloride, calcium, albumin, and blood glucose levels, white blood cell count and age. Based on these results, test items related to white blood cells and electrolytes could be used as indicators to identify IGT patients.