Abstract
Glycated hemoglobin ($HbA_{1c}$, A1C) is a widely used marker of chronic glycemia, reflecting average blood glucose levels over a 2- to 3-month period of time. Recently role of A1C in diagnosing diabetes has been extensively reviewed and International Expert Committee and American diabetes Association recommended the use of the A1C test to diagnose diabetes, with a threshold of ${\geq}$ 6.5%. The diagnostic A1C cut point of 6.5% is associated with an inflection point for retinopathy prevalence, as are the diagnostic thresholds for plasma glucose levels. But A1C levels vary with different races. Meta-analyses for previous studies regarding A1C cut off value for plasma glucose in Koreans and determination of A1C cut point based on the development of diabetic microvascular complications in community based cohorts should be performed to establish diagnostic A1C cut point in Korean population.