HbA1c is the major form of glycated haemoglobin in blood. Its synthesis is essentially irreversible and its concentration mainly depends on the concentration of glucose to which the erythrocytes are exposed and on the life-span of erythrocytes. As a result, the rate of HbA1c is representative of the average blood glucose concentration during the 6 to 8 weeks preceding the test.
Unlike the rate of glucose, the rate of HbA1c is independent of changes related to diet and exercise. Performing the test regularly is therefore recommended for monitoring glycemic control of diabetic patients. The level and change of this rate allow defining appropriate means to manage diabetes and prevent its complications.