A blood sample is needed. Some methods only require a quick finger stick. Others may need a sample of blood from a vein. For information on how this is done, see: Venipuncture.
How to prepare for the test
No special preparation is needed.
How the test will feel
When the needle is inserted, you may feel a slight pinch or some stinging. Afterward, there may be some throbbing.
Why the test is performed
Your doctor may order this test if you have diabetes. It shows how well you are controlling your diabetes.
The test may also be used to screen for diabetes.
An HbA1c of 5.6% or less is normal.
The following are the results when the HbA1c is being used to diagnose diabetes:
Normal: Less than 5.7%
Pre-diabetes: 5.7% to 6.4%
Diabetes: 6.5% or higher
If you have diabetes, you and your doctor or nurse will discuss the correct range for you. For many people the goal is to keep your level at or below 6.5 - 7%.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results. The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.
What abnormal results mean
Abnormal results mean that you have had high blood sugar levels over a period of weeks to months.
If your HbA1c is above 6.5% and you do not already have diabetes, you may be diagnosed with diabetes.
If your level is above 7% and you have diabetes, it often means that your is not well controlled. Your target HbA1c should be determined by you and your health care provider.
In general, the higher your HbA1c, the higher the risk that you will develop problems such as:
Shehzad Topiwala, MD, Chief Consultant Endocrinologist, Premier Medical Associates, The Villages, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine, and David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.