The comparison of ion exchange-high performance liquid chromatography (IE-HPLC) and capillary electrophoresis (CE) for HbA1C measurement

Background: HbA1c is glycosylated hemoglobin that routinely performed in a patient with Diabetes Mellitus. There are several methods for HbA1c measurement. One of them is based on the molecular charge such as High-Performance Liquid Chromatography (HPLC) and Capillary Electrophoresis (CE). Each method has its advantages and disadvantages. Thus, the selection of HbA1c measurement method is an important thing. This study was aimed to compare HbA1c measurement with HPLC and CE method. Methods: HbA1c measurement was done by HPLC and CE methods in 110 patient samples which have data of average blood glucose level during three months. We investigate the correlation of HbA1c results with average blood glucose level during three months, precision, methods comparison and interference including Hb variant. This study was conducted in the Central Laboratory of dr. Saiful Anwar Hospital during March-August 2018. Correlation analysis was done by Pearson analysis while precision test and methods comparison were done by Bland Altman Plot and Passing-Bablok Regression analysis. Results: There were correlation between estimated Average Glucose from HbA1c (eAGHbA1c) calculation with an average blood glucose level during 3 months in both methods. From precision test we found intraassay coefficient of variation in normal level (HbA1c +/- 5%) by HPLC vs CE was 1,7% vs 0.63% and in high level (HbA1c +/- 11%) was 0,59% vs 0,61% and inter-assay coefficient of variation by HPLC vs CE was 2,47% vs 2,17%. Method comparison results showed a strong correlation on both methods. The results of HbA1c in the group without Hb variant by CE method was slightly lower than HPLC. In Hb variant group, the CE method was slightly higher than HPLC, but it was not significant for HbA1c interpretation. Conclusion: HbA1c measurement by HPLC and CE method are comparable, and there is no significant difference in the results obtained.