Validation of Use of Boronate Affinity Chromatography to Measure Glycohemoglobin in the Presence of Hemo- globin S and C Traits by a Mass Spectrometry Reference

Glycohemoglobin (GHB) is routinely used both as an index of mean glycemia and as a measure of risk for the development and progression of diabetes complications (1, 2). Because the prevalence of diabetes is higher for non-Hispanic blacks than in non-Hispanic whites (3) and at least 10 % of black Americans have either hemoglobin S (HbS) or HbC trait (4), it is probable that at least 150 000 Americans with diabetes have HbS or HbC trait. Previous studies have shown that some GHB methods yield inaccurate results with samples heterozygous for HbS or HbC (5–9). Many of these interference studies have used boronate affinity chromatography as a refer-ence method based on the assumption that this method should not be influenced by the presence of Hb variants (10). Because measurement of GHB by boronate affinit