Combining metformin with insulin in the treatment of Type 2 diabetes has been found to reduce the risk of mortality, according to a new study.
The research, recently published in PLOS ONE by a team from Cardiff University in Wales, found that patients on insulin and metformin showed a 40% reduced risk for death and a 25% lower risk for major adverse cardiac events (MACE) versus patients treated only with insulin. The combination, however, didn’t show a significant reduction in cancer.
The study used the Clinical Practice Research Datalink, which captures longitudinal data from 660 primary care practices in the U.K. The data were collected from 2000 to 2013 for patients with a diagnosis of Type 2 diabetes, those with prescriptions written for at least two classes of glucose-lowering medication besides insulin, or patients with a diagnosis of Type 2 and a prescription for glucose-lowering medications besides insulin.
“These results from a retrospective analysis are not surprising and support what we already know,” Dr. Jason Baker, an endocrinologist at Weill Cornell Medicine, NY, told Medscape News. “It is reassuring and a reminder that insulin alone may not be appropriate for some of our patients.”
The researchers noted that the population of people receiving insulin in combination with metformin may be healthier than the monotherapy group. And for patients getting insulin alone, the researchers found that those prescribed high-dose insulin were at a 28% increased risk for all-cause mortality versus those getting low-dose insulin. Additionally, the risk for MACE wasn’t significantly reduced for the low-dose group.
Though insulin was used mainly as a monotherapy in the 1990s, the treatment goals for patients with Type 2 diabetes have since changed. In the past decade, Type 2 has been seen as a cardiovascular risk by major health organizations including the American Heart Association and the American Diabetes Association.