What is an A1c test?

Hemoglobin is a protein inside red blood cells. It is the part of the red blood cell that carries oxygen from the lungs to the rest of the body. Hemoglobin also carries sugar, because sugars can stick to all kinds of protein in the body. Once sugar sticks to hemoglobin it is stuck there for the life of the red blood cell, about 3-4 months. The more sugar there is in the blood, the more will end up stuck to the hemoglobin, which increases the A1c level. A1c is a measure of how much sugar is stuck to the hemoglobin.

The A1c reading tells you and your patients what their average blood sugar level has been for the past 2 to 3 months. If there is a lot of sugar in their blood and the average blood sugar has been high for the past few months, then their A1c will be high. The A1c test allows you to see overall how good your patients' control has been.

An A1c test higher than 7% is a likely indication that diabetic-related complications are drawing near. These can vary, but range from blindness and impotence to a stroke or heart attack. If an A1c test returns at 8% or greater, something needs to be changed. The patient should work with his or her doctor to develop more effective strategies for controlling blood sugar levels.

Changes in this plan are expected from time to time and will help bring their A1c closer to normal. When your patients' A1c is closer to normal (4-6%) then a suitable strategy has been implemented to help them stay healthy. A1c tests themselves also help to improve glycemic control, and the result can be easily converted into an average blood glucose value, useful for other analyses.

Research shows that good blood sugar control does lower their risk of developing major related health problems including heart disease, stroke, kidney disease, eye disease, nerve damage, amputations and circulation problems. By helping keep your patients' blood sugar close to normal, you can stop or delay the damage high blood sugar does to blood vessels and nerves.

Depending on the type of diabetes  that you have, how well your diabetes is controlled, and your doctor, your A1c may be measured 6 to 12 times each year. The American Diabetes Association recommends testing your A1c at least 6 times a year. When someone is first diagnosed with diabetes or if he or she has not yet gained control of the disease, A1c tests may be ordered more frequently.

For diagnostic and screening purposes, A1c may be ordered as part of a health checkup or when someone is suspected of having diabetes because they have signs or symptoms of increased blood glucose levels (hyperglycemia) such as:

• Increased thirst
• Increased urination
• Fatigue
• Blurred vision
• Slow-healing infections