An overview of A1C Test
An A1C test is a blood test used to diagnose and monitor diabetes. It measures the percentage of hemoglobin proteins in the blood that are coated with sugar over a period of two to three months. The higher the A1C level, the poorer the blood sugar control and the higher the risk of diabetes complications. Results are reported as a percentage, with below 5.7% considered normal, 5.7% to 6.4% indicating prediabetes, and 6.5% or higher on two separate tests indicating diabetes.
What is A1C Test used for?
An A1C test is primarily used for diagnosing type 1 and type 2 diabetes and monitoring blood sugar levels in individuals living with diabetes. It measures the average blood sugar level over the past two to three months by determining the percentage of hemoglobin proteins in the blood that are coated with sugar (glycated). The results can help healthcare providers diagnose prediabetes, adjust treatment plans, and monitor the effectiveness of diabetes management.
How often should A1C Test be performed?
The frequency of A1C tests depends on the type of diabetes, your treatment plan, how well you're meeting treatment goals, and your primary care doctor's clinical judgment. The recommended frequency ranges from once a year for prediabetes to four times a year for individuals taking insulin or having trouble keeping blood sugar levels within the target range. Your healthcare team will determine the appropriate frequency for your A1C test based on your individual circumstances.
How to prepare for A1C Test?
No preparation is needed for an A1C test. Fasting is not required, so you can eat and drink normally before the test.
How is A1C Test conducted?
The A1C test is a blood test that measures your average blood sugar level over the past two to three months. A healthcare provider will take a blood sample by inserting a needle into a vein in your arm or pricking your finger tip with a small lancet. The blood sample is then analyzed in a lab. Fasting is not required for this test.
How are A1C Test results reported?
A1C test results are reported as a percentage, which corresponds to average blood sugar levels over the past 2-3 months. Results below 5.7% are considered normal, 5.7% to 6.4% indicate prediabetes, and 6.5% or higher on two separate tests indicate diabetes. A1C test results are commonly used to diagnose type 1 and type 2 diabetes and monitor blood sugar control in individuals with diabetes.
Understanding the report
A1C test results are interpreted based on the percentage of hemoglobin proteins in the blood that are coated with sugar. Higher A1C percentages correspond to higher average blood sugar levels over the past two to three months. Results below 5.7% are considered normal, 5.7% to 6.4% indicate prediabetes, and 6.5% or higher on two separate tests indicate diabetes. An A1C level of less than 7% is a common treatment target for most people with diabetes. Self-monitoring of blood sugar levels at home helps track whether you are meeting your A1C target.
Limitations and Considerations
Limitations of the A1C test include factors that may interfere with its accuracy such as pregnancy, recent or heavy blood loss, recent blood transfusion, conditions resulting in insufficient red blood cells (anemias), and the presence of hemoglobin variants. Hemoglobin variants are more common among people of African, Mediterranean, or Southeast Asian descent and may lead to inaccurate A1C test results.