Reappraisal of HbA1c in the Aspect of Diagnosis and Management
Korean Clinical Diabetes
Diabetes is under diagnosed. Many people with diabetes do not know they have it, and the average lag between onset and diagnosis is 7 yr. Therefore reconsideration of criteria for diagnosing diabetes was essential. For decades, the diagnosis of diabetes has been based on glucose criteria, either the fasting plasma glucose or the 75-g oral glucose tolerance test. HbA1C is a widely used marker of chronic glycemia, and plays critical role in the management of the patient with diabetes. Prior
... ia have not used the HbA1C for diagnosis of diabetes, in part due to lack of standardization of the assay. However, HbA1C assays are now highly standardized so that International Expert Committee recommended the use of the HbA1C test to diagnosis diabetes, with a threshold of ≥ 6.5%, and ADA affirms this decision. The HbA1C has several advantages to the fasting glucose, including greater convenience and preanalytical stability, and less day-to-day perturbations. But the diagnostic test should be standardized, and the ADA comments that this test should be performed using a method that is certified by the National Glycohemoglobin Standardization Program (NGSP) and standardized or traceable to the Diabetes Control and Complications Trial reference assay.