Metformin works better in African Americans than whites, study finds

The type 2 diabetes drug metformin may be more effective in African Americans than white diabetic patients, according to a new study published online in the Journal of Clinical Endocrinology and Metabolism.
Clinical trials of metformin in the past largely involved white type 2 diabetes patients, so a group of researchers set out to examine how the drug performed in an African American population.
The team examined medical data from 19,673 diabetic Americans, 8,783 of whom were white and 7,429 African American, who were prescribed metformin medication from 1997-2013. To gauge long-term blood glucose control, the researchers had at least two hemoglobin A1c (HbA1C) test readings that were taken at least four months apart while the patients were on metformin.
African American patients on the maximum dose of metformin showed greater improvements in blood glucose control, with HbA1C readings for this group falling by an average of 0.9%, compared to a 0.42% reduction among white patients on the maximum dose – a significant difference.
“Our findings suggest that African Americans who have diabetes actually respond better to metformin than whites,” said study author, L. Keoki Williams, of Henry Ford Health System in Detroit.
“When one considers that the goal HbA1c level for individuals being treated for diabetes is less than 7% and that the average starting HbA1c level in our patients was around 7.5%, these differences in treatment response are clinically important.
“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 in the former group.”
This week it was revealed that the number of people living with diabetes in America rose by 3 million between 2010 and 2012 and now stands at more than 29 million, with the vast majority of these cases being type 2 diabetes.