The effect of hemoglobin variants on high-performance liquid chromatography measurements of glycated hemoglobin

INTRODUCTION: Glycated hemoglobin (HbA1c) is routinely utilized to monitor long-term glycemic control. The presence of hemoglobin (Hb) variants may lead to a false HbA1c measurement. This study was an investigation of the effects of both common and rare Hb variants on the level of HbA1c measured with high-performance liquid chromatography (HPLC).
METHODS: The HbA1c level of a total of 391 patients without Hb variants (HbAA, n=44) and with Hb variants (HbAS, HbSS, HbSS(A), HbSS(F), HbAD, HbAE, HbAF, HbD-Iran/D-Iran, HbD-Los Angeles/A, HbE-Saskatoon/E-Saskatoon, HbEE, HbG-Coushatta/A, HbOArab/OArab, HbSE, and Hb Stanleyville II, n=347) was measured using an HPLC analyzer.
RESULTS: The HbA1c level of all of the Hb variants but HbStanleyville II and HbG-Coushatta/A was extremely low. However, when the Hb variants were considered as a single group, a statistically significant difference was seen in comparison with the group that had no Hb variants (p<0.001).
DISCUSSION AND CONCLUSION: It was determined that the measurement of HbA1c can be adversely influenced by the presence of some Hb variants. Hemoglobin variants should be investigated when the HbA1c level is incompatible with blood glucose.