What is the HbA1C test and why is it used to check for diabetes?

HbA1C Test

• The HbA1c test, also known as the hemoglobin A1c test or glycated hemoglobin test, is a blood test that measures the average blood sugar level over the past 2-3 months.

• It is one of the commonly used tests to diagnose prediabetes and diabetes. Higher A1C levels are linked to diabetes complications.

• When sugar enters the bloodstream, it attaches to hemoglobin. People with higher blood sugar levels have more sugar attached to their hemoglobin. The A1C test measures the percentage of the red blood cells that have sugar-coated hemoglobin.

• The HbA1C levels are provided as either a percentage or in mmol/mol (which stands for millimoles per mole). A mole is a unit of measurement often used for chemical substances. 

• An Hb1A1C below 5.7% is considered normal; between 5.7% and 6.4% may indicate you are pre-diabetic; and 6.5% or higher can indicate diabetes. 

• The test’s results may change under certain conditions, including if a patient has kidney or liver failure, severe anaemia or a blood disorder such as thalassaemia and under certain medications including steroids, opiates or dapsone (a drug used to treat leprosy).