Hemoglobin A1c and the Estimated Average Glucose
Diagnosis of Diabetes

July 2009
The current diagnosis of diabetes includes one of the following: a fasting plasma glucose greater than or equal to 126 mg/dL, symptoms of hyperglycemia and a random plasma glucose greater than or equal to 200 mg/dL or a 2 hour glucose concentration great than or equal to 200 mg/dL after the oral glucose tolerance test. It is also recommended that confirmatory testing be performed on a different day unless there is clear evidence of hyperglycemia.
Diagnosis of Diabetes |
Jump to section:
- Introduction
- US Diabetes Prevalence
- Diagnosis of Diabetes
- Categories of Glucose Values
- Importance of Diagnosis
- Role of the Laboratory
- Fasting Plasma Glucose
- Fasting Plasma Glucose
- Hemoglobin A1c (HbA1c)
- Glycation
- HbA1c Concentration
- Diabetes Treatment Goals
- HbA1c Methods
- Hemoglobin Variants
- Hemoglobinopathies
- Reporting HbA1c as an eAG
- HbA1c and Average Glucose
- Derivation of Estimated Average Glucose (eAG)
- HbA1c/eAG Table
- Limitations
- Endorsement of eAG
- HbA1c for Diagnosis of Diabetes
- Disadvantages
- International Expert Committee Report on the Role of the A1c Assay in the Diagnosis of Diabetes
- HbA1c at Mayo Clinic
- Conclusions
- Questions?


