Bae JC et al. – A HbA1c cut–point of 5.7% is a suitable value for predicting future diabetes. It is reasonable to consider a HbA1c range of 5.7–6.4% as a category of increased risk for diabetes in Korean, similar to an IFG or IGT.

• A retrospective analysis was conducted among subjects who participated in comprehensive health check–ups annually for 5 years.
• A total of 9723 subjects were classified into 12 categories based on the baseline HbA1c level.

• During 4 years, 601 of the 9723 subjects (6.2%) developed diabetes.
• Based on ROC analysis, a HbA1c of 5.7% gave an optimal sensitivity of 62% and specificity of 85% to predict diabetes.
• The point showing a substantial difference in the Kaplan–Meier curves was a HbA1c of 5.7%.
• The incidence of diabetes was 20.8% among subjects with a baseline HbA1c of 5.7–6.4%.
• The hazard ratio of developing diabetes was 6.5 (95% CI, 3.7–10.2) in the subjects with a HbA1c of 5.7% compared with the bottom category of HbA1c (<5.0%).