HgbA1C measures the concentration of glycosylated hemoglobin in the blood
HgbA1C is the standard test for monitoring long term glycemic control for patients with either type 1 or type 2 diabetes mellitus
The value of HgbA1C reflects the average blood sugar level for the prior 2-3 months
Approximately 8% of hemoglobin A is made up of minor components that are chemically slightly different. They include: hemoglobin A1c, A1b, A1a1, and A1a2.
Glycosylated hemoglobin is the hemoglobin (Hgb) in the RBC that has become spontaneously bound to glucose, through a nonenzymatic process, during its 120-day circulating life span.
This formula by Rohlfing, et al., allows prediction for HgbA1C from Mean Plasma Glucose (MPG) or vice-versa.
Rohlfing CL, Wiedmeyer HM, Little RR, et al. Defining the relationship between plasma glucose and HbA(1c): analysis of glucose profiles and HbA(1c) in the Diabetes Control and Complications Trial. Diabetes Care. 2002;25(2):275-8.