Test Code LAB4112 HEMOGLOBIN A1C (HBA1C)
Additional Codes
Labcorp 001453 or 102525
Interpath 2051
Quest 496
Specimen Type
Whole blood Lavender top tube (EDTA)
Specimen Volume
4 mL
Minimum Volume
2 mL in Adult sized Lavender tube
Turnaround Time
STAT: 1 hour
Routine: 4 hours
Test Schedule
Daily
Sample Stability
Room Temp: 3 days
Refrigerated: 7 days
Reference Ranges
Hgb A1c 4.2 – 5.6%
A1c values of 5.7-6.4% indicate an increased risk for diabetes mellitus.
A1c values of greater than or equal to 6.5% are diagnostic of diabetes mellitus.
The American Diabetes Association considers a result of less than 7% to be the goal of diabetic therapy.
Estimated Average Glucose mg/dL
The ADA considers an eAG result of less than 154 mg/dL to be the goal of diabetic therapy. Estimated Average Glucose calculated from hemoglobin A1c by use of ADA recommended formula.
Synonyms
HGBA1C; Hemoglobin A1C; Glyco; Glycated Hemoglobin
CPT Codes
83036
Test Components
Hgb A1c, %; Estimated Average Glucose, mg/dL.
Clinical Information
Hemoglobin A1C (HbA1c) is the fraction of hemoglobin A that is first reversibly, then irreversibly glycated at one or both N-terminal valines of the β-chain. The longer the red blood cells (RBCs) are in circulation and the higher the ambient glucose levels, the higher the concentration of HbA1c. HbA1c reflects the average blood glucose level during the preceding 2 to 3 months. The HbA1c assay is useful as an aid in the diagnosis of diabetes mellitus, identification of patients at risk of developing diabetes and monitoring patients with diabetes mellitus.
To monitor diabetic patients, it is recommended that the glycemic goals are individualized following current professional societies such as the American Diabetes Association. Patients in the range of 5.7 to 6.4 %HbA1c (39 to 46 mmol/mol) would be in the category of increased risk for diabetes and results ≥6.5% (48 mmol/mol) may aid in the diagnosis of diabetes. Several studies have shown that the long term control of diabetes can prevent complications such as cardiovascular disease, retinopathy, and neuropathy. Measurement of HbA1c can be invaluable in the monitoring of glycemic control of diabetic patients.