Different Ethnicities, Same Diabetic Eyes

Retinopathy and HbA1c linked without ethnic differences

(RxWiki News) In people with diabetes, out-of-control blood sugar can spell trouble. High blood sugar can lead to a number of problems, including eye damage.

A recent study showed that higher blood sugar levels were linked to retinopathy (damage to the retina of the eye), regardless of ethnicity.

In other words, the retinopathy rate associated with each HbA1c category was no different across ethnic groups.

"Control your blood sugar to prevent eye complications."

Current recommendations for the use of HbA1c (a measure of blood sugar over 3 months) in diabetes screening and diagnosis aim to single out those with the highest risk for certain diabetic complications, said Elizabeth Selvin, MPH, PhD, of Johns Hopkins Bloomberg School of Public Health, and colleagues in background information to their study.

However, there is some disagreement about what risk HbA1c levels represent for people of different ethnicities.

For their research, Dr. Selvin and colleagues set out to see if the link relationship between HbA1c and retinopathy differed between ethnic groups.

For people without diabetes, a normal HbA1c level generally falls between 4.5 and 6 percent. A level of 6.5 percent or more indicates a person has diabetes. As HbA1c levels rise, the risk of diabetes complications also rises.

In the study, the mean HbA1c of those without diabetes was:

  • 5.5 recent among whites
  • 5.7 percent among blacks
  • 5.6 percent among Hispanic Americans

In comparison, the mean HbA1c of those with diabetes was:

  • 6.9 percent among whites
  • 7.5 percent among blacks
  • 7.7 percent among Hispanic Americans

Overall, black patients had the highest rates of retinopathy.

Despite the different HbA1c levels of ethnic groups, the relationship between HbA1c levels and retinopathy was equally strong in all three ethnic groups. 

According to the authors, these findings "do not support ethnic-specific cut points for HbA1c for diagnosis or screening of diabetes."

The study was published October 15 in Diabetes Care, a journal of the American Diabetes Association.

Review Date: 
October 15, 2012