A1C Test and the Estimated Average Glucose (eAG) HF#4798

What does the A1C test measure?

 

The A1C test (Glycosylated Hemoglobin or Hemoglobin A1C) measures the average amount of sugar in your blood over the past 2-3 months.  It is a measure of how much sugar is attached to the hemoglobin part of your red blood cells.

 

How is the A1C test done?

 

A blood sample is drawn.  The test is done in the lab.  This test does not require fasting.

 

When is the A1C test done?

 

The A1C test may be done as often as every 2 months, but most often it is done every 3-4 months since this is the lifespan of a red blood cell.  The test may be done less often if your blood sugars are in good control.

 

Why is the A1C done?

 

Research shows that keeping blood sugar levels close to normal can greatly reduce the chance of problems related to diabetes.  Studies show that any decrease in A1C will help to decrease and prevent the long term problems from diabetes.  One large study showed that keeping the A1C below 7% lowered the risk of these problems.

• Retinopathy (eye damage) lowered by 76%.
• Nephropathy (kidney disease) lowered by 35-56%.
• Neuropathy (nerve problems) lowered by 60%.

Any improvement of A1C levels over time will help to keep you in better health!

 

What do the A1C results mean?

 

The A1C measures your average blood sugar 24 hours a day, 7 days a week, for 2-3 months.  The A1C value is given as a percentage.  It may be more helpful to translate this A1C value into an average glucose value.  This is called the estimated Average Glucose or eAG.  The eAG uses the same values and units (mg/dL) that you see when you check your blood sugar with your meter or get a report from the lab.  This may help you to see how your daily blood sugar checks relate to your A1C.

 

This chart helps to show how your A1C value relates to estimated Average Glucose (eAG).

 

 

An A1C of 7% or less, the goal for many people with diabetes, is equal to an eAG of 154 mg/dL.

 

Keep a record of your A1C and eAG results over time.  Compare your results to other recent values as well as to the normal range to see if blood sugar control is getting better.  It might also be helpful to compare the eAG to your 30 day average blood sugar in your meter.  You and your diabetes care team will decide on your A1C goal.

 

My A1C Goal is __________ %      eAG __________ mg/dL

 

MY RESULTS/ DATE	A1C %	eAG mg/dL

 

Talk with your health care team about the pattern of your A1C test results. Results may suggest that you need to adjust your diet, activity, insulin, and/or pills.  The goal is to keep A1C levels as close to normal, or as low as possible, without frequent low blood sugars.

 

The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.

Last Updated: 07/05/2012

Copyright © 07/05/2012 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#4798

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