There’s now plenty of evidence that U.S. ethnic minority groups tend to have higher A1c levels than whites. (Your A1c is the percentage of your hemoglobin cells that are glycated – have sugar stuck to them. The higher your blood sugars are, the more sugar sticks to your hemoglobin over time, and the higher your A1c is.)
The disparity is usually rather smugly attributed to differences in self-care: the assumption has been made that minorities just don’t manage their diabetes as well. But now that conclusion has been called into question by research indicating that blood sugar might stick to hemoglobin more easily in minorities than in whites, leading to higher A1c’s in spite of the same levels of sugar control over time. If you’re African American, an A1c of 6% might indicate lower average glucose than the same A1c in a white person.
To arrive at their conclusions, researchers reporting in Diabetes Care divided 3,819 people with impaired fasting glucose into five groups by ethnicity: white, Hispanic, Asian, American Indian, and African American. After “adjusting for factors,” they found that among the different groups, people who had the same blood glucose levels ended up with different A1c’s. The average A1c level among whites was 5.78%, compared to 5.93%, 6.00%, 6.12%, and 6.18% for Hispanics, Asians, American Indians and African Americans, respectively.
The researchers concluded that the A1c, because it is apparently affected by factors other than blood sugar alone, may not be an accurate measure of average blood glucose levels across ethnicities.
Source: Diabetes Care, November 2007; MedlinePlus