Hemoglobin A1C (HbA1c)

Cleveland HeartLab H, Metabolic, Test

CPT Code:

Hemoglobin A1c: 83036
Hemoglobin A1c with Reflex to Glycomark: If Hemoglobin A1c is >5.9% and <8.1%, then GlycoMark will be performed at an additional charge (CPT 84378).

Order Code:

Hemoglobin A1c: C145
Hemoglobin A1c with Reflex to GlycoMark: C522

Includes: HbA1c and Estimated Average Glucose
ABN Requirement:  No
Synonyms: Hemoglobin A1c; HbA1c; HgbA1c; Glycohemoglobin; Glycated Hemoglobin; Glycosylated Hemoglobin


Hemoglobin A1c: EDTA whole blood
Hemoglobin A1c with Reflex to GlycoMark: EDTA whole blood and serum

Volume: 4.0 mL
Minimum Volume: 2.0 mL


Hemoglobin A1c: EDTA (Lavender Top tube)
Hemoglobin A1c with Reflex to GlycoMark: EDTA (Lavender Top tube) and Gel-barrier Tube (SST)


  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 8-10 times immediately after draw. DO NOT SHAKE.
  3. Do not centrifuge.

Transport: Store EDTA whole blood at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box.


Ambient (15-25°C): 3 days
Refrigerated (2-8°C): 7 days
Frozen (-20°C): 6 months

Causes for Rejection: Specimens other than EDTA whole blood; improper labeling; samples not stored properly; samples older than stability limits

Methodology: Turbidimetric Inhibition Immunoassay (TINA)

Turn Around Time: 1 to 3 days

Relative Risk:

Hemoglobin A1c:

Age Low Risk
Moderate Risk
High Risk
All Ages <5.7 5.7-6.4 >6.4


eAG (Estimated Average Glucose):

Age Low Risk
Moderate Risk
High Risk
All Ages <117 117-137 >137


HbA1c Reflex Value for GlycoMark:

Age %
All Ages 6.0-8.0

For additional information on the GlycoMark test, please see www.clevelandheartlab.com/tests/glycomark/

Clinical Significance: HbA1c testing is used to monitor the glucose control of diabetics to minimize complications of chronically elevated glucose levels. It is also used for the diagnosis of diabetes and pre-diabetes in individuals with or without symptoms of hyperglycemia.

Limitations: The A1c test should not be used for the diagnosis of diabetes in pregnant women, individuals who have experienced recent severe bleeding or who have received blood transfusions, individuals with chronic liver or kidney disease or individuals with certain blood disorders.

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.