Improvement in Prediction of Incident Type 2 Diabetes Using the 2003 Criteria of Impaired Fasting Glucose: Results From a Population-Based 6.5-Year Follow-Up Study in IRAN

To investigate whether using the 2003 criteria for impaired fasting glucose (IFG) improves the prediction of Type 2 diabetes mellitus (T2DM) in comparison to the 1997 criteria. A total of 5794 non-diabetic subjects, aged 42±13 years, were followed for 6.5 years. T2DM was defined based on the WHO 1999 criteria. Cox regression analysis was used to calculate the relative risk (RR) of developing T2DM. Model discrimination was assessed by calculating the area under the receiver operating characteristic curve (AUC). During the follow-up, there were 351 new cases of T2DM. In univariate analysis, the RR of the 1997 and 2003 criteria were 9.6(7.5-12.3) and 8.4(6.4-10.0) respectively. After adjustment for a full range of diabetes risk factors, the RR of the 2003 criteria was higher compared to that of the 1997 definition [RR (95%CI): 3.3(2.6-4.2) vs. 2.4(1.8-3.2) respectively]. Inclusion of the 2003 criteria in the multivariate model significantly improved discrimination in comparison to the 1997 definition [AUC (95%CI): 0.78(0.74-0.83) vs. 0.74(0.70-0.79), P<0.01]. When fasting glucose is used in community screening for pre-diabetes state, the 2003 IDF criteria yield significantly better results than the original criteria for prediction of future T2DM.