The HbA1C test is a simple yet useful blood test that helps to diagnose and monitor blood glucose control in people suffering from diabetes. Also known as glycated hemoglobin or glycosylated hemoglobin, this potential test is an indicator that determines the increase and decrease in blood glucose levels that could have abnormally fluctuated over the last three months. Haemoglobin is a protein located in red blood cells of the body that effectively carries oxygen through the system. The levels of HbA1c are directly related to the amount of glucose in the blood. Measuring the amount of hemoglobin in the blood with glucose attached (of the last three months’ time) helps to diagnose pre-pre-diabetes symptoms in people and the status of ongoing diabetes along with the effectiveness of its treatment. Since the red blood cells can survive in the body for up to four months, HbA1C testing can easily find out how much sugar the bloodstream contains over the past three months. The HbA1C test is different from the normal blood glucose test because the latter gives information on how much sugar is in the blood at that very moment whereas HbA1C provides an average of three months which becomes ideal in monitoring besides managing this chronic health disorder.

Since the test is an effective indication of blood glucose levels from the previous three months, physicians recommend that people with diabetes get HbA1c testing done frequently. This testing is done in addition to home blood glucose monitoring to check blood levels daily through a glucometer.  A raised level of A1C from the last 12 weeks correlates with an increased risk of developing diabetes in the case of a non-diabetic and complications such as diabetic retinopathy in the case of diabetic people. An HbA1C value higher than 6.5 implies one has diabetes.

A simple blood test, this testing does not require any special preparation. Blood sample is taken by your doctor or at a pathology lab. As a matter of fact, unlike many diabetes-related tests, there is no need to fast while taking this test. One can go for it even after having eaten a regular meal. HBA1C measures the percentage of hemoglobin stuck to glucose, which reflects the concentrated levels of average blood glucose or glycosylated hemoglobin. It can be measured in percentages or units of mmol. Both ways give accurate results available to the patient within 24 to 48 hours. A normal HbA1c result ranges between 3.5 to 6 percent or 15-42 mmol.

One should go for a baseline A1C test if:

• The result has already shown that you have prediabetes or diabetes
• You are over age forty-five, overweight, and have risk factors for getting type 2 diabetes
• Your result is normal, but you are over forty-five, are at risk due to hereditary factors, or have had gestational diabetes at some point in time

It is not necessary that when HbA1C levels are high, one necessarily has diabetes. Certain causative factors can show raised or low HbA1c levels. For instance, just like our blood group types some of us have type A hemoglobin or adult hemoglobin, while some of us may be born with a completely different hemoglobin variant. This is known as hemoglobinopathy and at times can cause inaccurately high or low HbA1c results. Moreover, some other factors such as iron deficiency, hemolytic anaemia, early or late pregnancy, blood loss, and chronic kidney and liver problems such as NAFLD, besides some ongoing medications or supplements during the time of testing like iron, folate supplements and Vitamin C, E and B12 supplements can create discrepancies in results. Nonetheless, HbA1C testing has been crucial in diagnosing mild to severe prediabetes and provides a reliable measure of chronic hyperglycemia thus successfully helping the patient to manage diabetes and prevent the occurrence of comorbidities.

Yes. Doctors recommend HbA1C for patients with borderline elevated blood sugar levels. Repeating this test every three months and being aware of the levels helps control blood glucose, with the help of dietary and lifestyle management, without medication.

Various labs use different analytical methods to measure Hemoglobin A1c. Labs use liquid chromatography to calculate the result as a ratio to total hemoglobin, and widely used techniques are immunoassay, enzymatic assay, capillary electrophoresis, or Boronate affinity chromatography (BAC).

The results may vary slightly depending on the technique and age of the patient. Persistent levels of elevated HbA1C are common among diabetic patients, but they may come down within the reference range in a person with reasonable control over glucose levels.

Here is how you read the results:

<5.7% is normal

5.7% to 6.4% is pre-diabetes

6.5% and above are diabetes

Doctors recommend HbA1C at least three times a year for patients on diabetic medication, coupled with lifestyle changes. This will help assess the treatment plan and check if the goals are met. Your doctor may change medication and dosage and recommend different lifestyle and dietary changes. Patients are advised to wait at least 6 weeks after making appropriate changes in medication, diet, and lifestyle changes to repeat the test.

The HbA1c test is beneficial to monitor long-term glucose control in people suffering from diabetes. It provides an overview of how well blood sugar levels have been managed over a few months. This can help in making accurate treatment decisions.

Yes. Certain conditions can affect HbA1c levels, such as anemia, hemoglobinopathies, and kidney failure. These health issues can impact the accuracy of HbA1c readings.

By and large, the general target HbA1c for many adults with diabetes is below 7%. However, targets can be vary based on age, health status, and other factors.

Maintaining a balanced diet, engaging in regular physical activity, managing stress, and adhering to prescribed medications can help lower HbA1c levels and improve overall glucose control.

Preeti Sharma has a master’s in electronic media and mass communication and certification in short-term writing from Florida. With close to a decade of experience, she specializes in crafting engaging blogs on beauty, veterinary care, and healthy cooking. Preeti is proficient in video editing tools and produces captivating and informative content across multiple platforms.

Hemoglobin A1C

Emily Eyth, Roopa Naik.