Haemoglobin A1c (HbA1c) testing, an indicator of blood sugar levels over the past 3 months, should be used as a screening and diagnostic test for diabetes. Drawbacks in existing methods of diagnosing diabetes, including the requirement that the patient fast and the lack of agreed-upon screening criteria, make it unnecessarily inconvenient for doctors to diagnose diabetes. A high percentage of people with diabetes are undiagnosed, which contributes to avoidable complications and death. American researchers believed that the long-established and universally accepted HbA1c test should be incorporated into the diagnostic criteria for diabetes. Three factors support this recommendation. HbA1c does not require patients to fast; HbA1c laboratory methods are now standardised and reliable; and errors that may affect the HbA1c result are uncommon and can be minimised with other tests. Based on their research and deliberations, they offer a few recommendations to make diabetes screening easier. The researchers also recommend that an HbA1c of 6.5 percent or greater be confirmed with another blood sugar test before a diagnosis is made. Finally, they call for specific criteria for diabetes screening and for establishing blood sugar levels that will indicate if further diagnostic testing should be done.
Journal of Clinical Endocrinology and Metabolism
June 2008