Useful For

Use: HbA1C (Glyco Hemoglobin) is an important tool in the
management of diabetes, especially insulin dependent
diabetes.  Because the average half-life of a red blood cell
is 60 days, glycosylated hemoglobin has been accepted as a
measurement that reflects the mean daily blood glucose
concentration and the degree of carbohydrate imbalance over the
preceding 2 months.
 

Test includes HbA1C,  Estimated average glucose
(EAG)

Limitations:  Abnormal red cell survival:  These
patients will exhibit decreased HbA1c due to shortened life span of
red blood cells.  Samples from patients with polycythemia or
post-splenectomy may exhibit increased glycosylated hemoglobin.

Hemoglobin A2:  Patients with increased hemoglobin A2 (>
1.5%) such as found in Thalassemia major may exhibit slightly
decreased glycosylated hemoglobin values.

Hemoglobin S and C:  Patients with homozygous SS or CC will
need to be monitored with a total glycated method because there is
virtually no hemoglobin A present.  Patients with the
heterozygous state are not affected.

Other Information:  The HbA1c method has been correlated with
the mean blood glucose concentrations. (Estimated average glucose
or EAG)

The following Linear Regression equation is used:
EAG mg/dL = 28.7 (HbA1c) – 46.7