Does Race Influence Glycosylated Hemoglobin Results?

Previous studies suggest that average blood glucose levels at given glycosylated hemoglobin (HbA_1c) levels differ across racial groups, but few studies have included continuous glucose monitoring (CGM) to evaluate this observation. In a substudy from the previously published GRADE diabetes trial (NEJM JW Gen Med Jan 1 2023), researchers examined whether correlations between HbA_1c level and 10-day average blood sugar recorded by CGM differed across racial groups.

Among 1500 participants, most identified as non-Hispanic white and non-Hispanic Black. After adjustment, correlations between HbA_1c level and average glucose were significantly different in non-Hispanic black participants than in other racial or ethnic groups. For example, across ave…