Glycohemoglobin is a blood test that checks the amount of sugar
(glucose) bound to
hemoglobin. Normally, only a small percentage of
hemoglobin in the blood (4% to 6%) has glucose bound to it. People who have
diabetes or other conditions that increase their blood
glucose levels have more glycohemoglobin than normal.
The glycohemoglobin A1c can be used to diagnose diabetes. The
glycohemoglobin A1c test checks the long-term control of blood glucose levels
in people with diabetes. Most doctors think the glycohemoglobin A1c level is
the best way to check how well a person is controlling his or her diabetes.
A home blood glucose test measures the level of blood glucose
only at that moment. Blood glucose levels change during the day because of
diet, exercise, and the level of insulin in the blood.
useful for a person who has diabetes to have information about the long-term control of blood
sugar levels. The glycohemoglobin test is one blood sample every 3 to 4 months,
and the test does not change with any recent changes in diet, exercise, or
Glucose binds to hemoglobin in red blood cells at a
steady rate. Since red blood cells last 3 to 4 months, the A1c
test shows how much glucose is in the
plasma part of blood. This test shows how well your
diabetes has been controlled in the last 2 to 3 months and whether your
diabetes medicine needs to be changed.
The A1c level can also help
your doctor see how big your risk is of developing problems from diabetes, such
as kidney failure, vision problems, and leg or foot numbness. The lower your
A1c level, the lower your chance for problems.
Why It Is Done
This test is done to:
- Diagnose diabetes.
- Check your
treatment for diabetes.
How To Prepare
You do not need to stop eating before
you have a glycohemoglobin test. This test can be done any time during the day,
even after a meal.
How It Is Done
The health professional taking a sample
of your blood will:
- Wrap an elastic band around your upper arm to stop the flow of
blood. This makes the veins below the band larger so it is easier to put a
needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is
- Put a gauze pad or cotton ball over the needle site as the needle
- Put pressure on the site and then put on a bandage.
How It Feels
The blood sample is taken from a vein in
your arm. An elastic band is wrapped around your upper arm. It may feel tight.
You may feel nothing at all from the needle, or you may feel a quick sting or