The American Association of Clinical Endocrinologists (AACE) today has approved the use of A1c as an additional diagnostic criterion for type 2 diabetes. An A1c of 6.5 or greater is now considered an alternate criterion for the diagnosis of type 2 diabetes.
The decision was announced in a position statement entitled “The AACE/ACE Statement on the Use of A1c for the Diagnosis of Diabetes.” The position statement can be found online here. The position statement also reviews the limitations of the test. For example, certain ethnic groups may have marginally elevated values which do not necessarily indicate diabetes.
The rationale for the use of A1c for diagnosis is based on data showing that retinopathy occurs in
individuals with an A1c ≥6.5% at approximately the same rate as in individuals who are diagnosed based on the current fasting and post-challenge glucose criteria. A 10% risk for retinopathy has historically served as the bench mark for diagnosing the presence of diabetes.
individuals with an A1c ≥6.5% at approximately the same rate as in individuals who are diagnosed based on the current fasting and post-challenge glucose criteria. A 10% risk for retinopathy has historically served as the bench mark for diagnosing the presence of diabetes.
Advantages of this new diagnosis:
- Does not require the patient t be fasting
- Can be done at any time that a visit is scheduled
- Simpler to perform than the 2 hr oral glucose test
- Less dependent on the patient’s health status at the moment of the blood draw.
The most common criteria currently used to diagnose diabetes are a fasting glucose of 126 or greater or a 2 hour value on a glucose tolerance test (GTT) greater than 200. Both tests require patients to fast for a minimum of eight hours prior to being tested. The GTT is a 2 hour series of glucose levels following the administration of a large amount of glucose.
The AACE Guidelines for the Management of Diabetes (link) use A1c of 6.5 or less as a goal for patients once they have been diagnosed with type 2 diabetes.
