The diabetes drug metformin offers more heart benefits than medicines in the sulfonylurea class, according to new research from Vanderbilt University. Cardiovascular disease is the leading cause of death in those with diabetes, with more than two-thirds of people with the condition dying of heart disease or stroke.
To compare the effects of metformin (brand name Glucophage and others) and sulfonylureas (glyburide [Diabeta, Glynase, Micronase], glipizide (Glucotrol), glipizide extended-release [Glucotrol XL], glimepiride [Amaryl]) on cardiovascular outcomes such as heart attack, stroke, and death, researchers looked at the charts of more than 250,000 veterans receiving health care at Veterans Health Administration hospitals across the United States. All subjects had Type 2 diabetes, and all had been started on either metformin or a sulfonylurea — either glyburide or glipizide, in this case of this study — for their condition. Roughly 155,000 took metformin, while approximately 100,000 were on a sulfonylurea.
After reviewing about a year’s worth of data on each participant, the researchers discovered that those who had been prescribed metformin had a lower risk of heart attack, stroke, and death than those who were prescribed a sulfonylurea, with those on metformin facing a 21% lower risk of being hospitalized due to a cardiovascular condition.
“We demonstrated that for every 1,000 patients who are using metformin for a year, there are two fewer heart attacks, strokes or deaths compared with patients who use sulfonylureas. I think this reinforces the recommendation that metformin should be used as the first medication to treat diabetes” noted lead author Christianne L. Roumie, MD, MPH.
The researchers noted that they could not determine whether metformin offers heart benefits or whether sulfonylureas pose a specific heart risk, adding that both could be possible. Limitations of the study include that subjects were not compared to a control group that was not taking oral medicines, and that 97% of the participants were males and 75% were white (meaning that researchers do not know whether the findings apply to women and racial minorities).
For more information, read the article “Popular Diabetes Meds Put to the Test,” or see the study’s abstract in the Annals of Internal Medicine. And to learn more about metformin, see our many pieces on the medicine.