Fast Five Quiz: Glycemic Control in Type 2 Diabetes

Romesh Khardori, MD, PhD


January 12, 2022

Figure 1. Glycemia test before a meal. Here, the glucometer indicates that the person is in hyperglycemia.

An A1c level 6.5% (48 mmol/mol) or greater meets the criteria for type 2 diabetes. There are several other criteria for the diagnosis of type 2 diabetes:

  • Fasting plasma glucose level 126 mg/dL (7.0 mmol/L) or higher, where "fasting" is defined as no caloric intake for at least 8 hours, or

  • 2-hour plasma glucose level 200 mg/dL (11.1 mmol/L) or higher during an oral glucose tolerance test, which 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

  • In a patient with classic symptoms of hyperglycemia or hyperglycemic crisis, a random plasma glucose level 200 mg/dL (11.1 mmol/L) or higher

Of note, in the absence of unequivocal hyperglycemia, diagnosis requires two abnormal test results from the same sample or preferably in two separate test samples.

The European Society of Cardiology Clinical Practice Guidelines on Diabetes, Pre-Diabetes and Cardiovascular Diseases, developed in collaboration with the European Association for the Study of Diabetes, recommend that the diagnosis of type 2 diabetes should be based on A1c and/or fasting plasma glucose. If it is still in doubt, an oral glucose tolerance test can be performed.

Learn more about the diagnosis of type 2 diabetes based on glycemic levels.


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