The glycated hemoglobin value represents the integrated values of glucose concentration during the preceding:

The glycated hemoglobin value represents the integrated values of glucose concentration during the preceding:

• A. 1-3 weeks
• B. 4-5 weeks
• C. 6-8 weeks
• D. 16-20 weeks

Answer: (C)

Glycated hemoglobin reflects long-term glycemic exposure because glucose gradually binds to hemoglobin as red blood cells circulate. Since red blood cells live about 120 days, the HbA1c level summarizes the average blood glucose over those weeks. In practice, this creates an averaging window of roughly 6–8 weeks, with more weight toward the recent weeks but still incorporating earlier weeks. Shorter timeframes (like 1–3 weeks) wouldn’t capture enough of the longer-term trend, while much longer spans would be muddled by older cells. Note that anything affecting red blood cell turnover can bias HbA1c, such as anemia, transfusion, or hemolysis.

Glycated hemoglobin reflects long-term glycemic exposure because glucose gradually binds to hemoglobin as red blood cells circulate. Since red blood cells live about 120 days, the HbA1c level summarizes the average blood glucose over those weeks. In practice, this creates an averaging window of roughly 6–8 weeks, with more weight toward the recent weeks but still incorporating earlier weeks. Shorter timeframes (like 1–3 weeks) wouldn’t capture enough of the longer-term trend, while much longer spans would be muddled by older cells. Note that anything affecting red blood cell turnover can bias HbA1c, such as anemia, transfusion, or hemolysis.