Abstract
The associations between glycosylated hemoglobin (HbA1c), fructosamine (FRA), and 1, 5-anhydroglucitol (1, 5-AG) as screening tests for diabetes mellitus and risk factors for the disease were assessed. A 75 g oral glucose tolerance test based on WHO criteria was performed and Hb A1c, FRA, and 1, 5-AG were measured in 401 subjects. Multivariate logistic regression analysis was used to evaluate the effect of age and body mass index (BMI) on the probability of having diabetes for each test and to calculate the predicted values individually. Receiver operating characteristic (ROC) curves for the three tests and for three logistic models were constructed and the areas under ROC curves for the data obtained were calculated. Although the area under the ROC curve for each logistic model was slightly higher than that for the corresponding single test, statistical analysis did not show significance. However, the ROC curves indicated that the specificities of each logistic model were significantly higher than those of the corresponding single test, when screening levels were selected for sensitivities above 80%. These results suggest that age and BMI improve the diagnostic accuracy of HbA1c, FRA, and 1, 5-AG for diabetes screening.
