What does HbA1c level in the blood indicate?
High-Yield Explanation
Glycosylated Hemoglobin (HbA1C) is the standard method for assessing long-term glycemic control. When plasma glucose is excessively elevated, it enters the erythrocytes, and glycates the amino group of lysine residues and the amino terminals of hemoglobin. This results in the formation of glycosylated hemoglobin. Since the half-life of an erythrocyte is typically 120 days, the level of glycated hemoglobin (HbA1c) reflects the mean blood glucose concentration over the preceding 2-3 months. Measurement of HbA1c therefore provides valuable information for management of diabetes mellitus. Ref: Harrison's Internal Medicine, 18th Edition, Page 2992 ; Harper's Illustrated Biochemistry, 28th Edition, Chapter 6 ; Tintinalli's Emergency Medicine : A Comprehensive Study Guide, 7th Edition, Chapter 218.