Based on this report, the ADA has recently changed its mind from a year ago, and the criteria for the diagnosis of diabetes now include elevated A1C levels. The information, published as part of the ADA's Clinical Practice Recommendations for 2010, in a document about the Diagnosis and Classification of Diabetes Mellitus indicates four ways to make the diagnosis, three using BGL as before, and now a new one based on elevated A1C levels:
1. A1C ≥6.5%. The test should be performed in a laboratory using a method that is NGSP certified and standardized to the DCCT assay.*
OR
2. Fasting plasma glucose ≥126 mg/dl (7.0 mmol/l). Fasting is defined as no caloric intake for at least 8 hours.*
OR
3. 2-hour plasma glucose ≥200 mg/dl (11.1 mmol/l) during an oral glucose tolerance test. The test should be performed as described by the World Health Organization, using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water.*
OR
4. In a patient with classic symptoms of hyperglycemia or hyperglycemic crisis, a random plasma glucose ≥200 mg/dl (11.1 mmol/l).
*In the absence of unequivocal hyperglycemia, criteria 1-3 should be confirmed by repeat testing.
After years of having patients come to the laboratory fasting, or having them swallow tons of gooey sweet syrup during a glucose tolerance test, the diagnosis of diabetes can now be made with a simple blood test, done at any time of day, with no concern whether the patient is fasting. Isn't science wonderful?
