Disparity in estimated average glucose due to different hemoglobin A1c methods and hemoglobin S trait.

摘要

A recent report has affirmed the existence of a mathematic relationship between a patient's hemoglobin Ale (HbAlc) value and the average glucose concentration (1). The American Diabetes Association has recommended that estimated average glucose (eAG) values be calculated from the measured HbAlc result and reported along with HbAlc (http:// professional.diabetes.org/glucosecalculator.aspx). However, clinical chemistry laboratories use a variety of HbAlc assays based on different principles that are not fully standardized (2). Thus, variable eAG results may be obtained when the same equation is used. Also, different HbAlc methods have variable susceptibility to interference from hemoglobin variants (3), which may further increase the difference in eAG values. The objective of this study was to compare eAG results calculated from HbAlc measured using a cation-exchange high-performance liquid chromatography (CE-HPLC) assay and turbidimetric immunoinhibition (TI) method in patients with normal and hemoglobin variants.