THURSDAY, June 12, 2014 (HealthDay News) -- Blacks with type 2 diabetes may fare better on the widely used drug metformin compared with whites, a new study finds.
Researchers analyzed data from more than 19,600 Americans who were prescribed metformin between 1997 and 2013. The team found that blacks had greater improvements in their blood sugar control than whites.
Study participants underwent at least two A1C blood tests at least four months apart while they took metformin. An A1C test measures a person's average blood sugar level over the previous three months.
The maximum dose of metformin was associated with a 0.9 percent decrease in A1C results among blacks, compared with a 0.42 percent decrease among whites -- a significant improvement.
The study is published online June 12 in the Journal of Clinical Endocrinology & Metabolism.
"Metformin is normally the first treatment physicians prescribe for type 2 diabetes, but the standard of care is based on clinical trials where the vast majority of participants were white," Dr. L. Keoki Williams, of Henry Ford Health System in Detroit, said in a journal news release.
"We wanted to examine how the drug performed in an African American population. Our findings suggest that African Americans who have [type 2] diabetes actually respond better to metformin than whites."
The target A1C level for diabetes patients is less than 7 percent, but the average A1C level among the patients in the study was about 7.5 percent. This makes the differences in responses of black and white patients to metformin "clinically important," Williams explained.
"Moreover, since African Americans are more likely to suffer from diabetic complications when compared with white individuals, it is heartening to observe that metformin is likely more effective at controlling blood glucose [sugar] in the former group," the researcher added.
About 26 million Americans have diabetes, with the vast majority of cases being type 2. Blacks are twice as likely as whites to be diagnosed with type 2 diabetes and have a higher rate of diabetes-related complications such as kidney failure, according to the U.S. Department of Health and Human Services' Office of Minority Health.
The U.S. National Institute of Diabetes and Digestive and Kidney Diseases has more about diabetes.