Patients with type 2 diabetes taking metformin and insulin may have a greater risk of cardiovascular disease and mortality compared to those taking metformin and sulfonylurea. The results of this study were published in the Journal of the American Medical Association.
Christianne L. Roumie, MD, MPH, from the Tennessee Valley Veterans Affairs Medical Center in Nashville, and colleagues conducted a retrospective cohort analysis of patients treated with metformin from 2001–2008 who later added insulin or sulfonylurea as a second-line medication. Of the 178,341 patients on metformin therapy, 2,948 added insulin and 39,990 added sulfonylurea. Compared to the metformin plus sulfonylurea group, patients taking metformn plus insulin were found to have a higher risk of cardiovascular events (42.7 vs. 32.8 events per 1000 person-years; adjusted hazard ratio [aHR], 1.30; 95% CI, 1.07–1.58; P=0.009) and greater mortality (33.7 vs. 22.7 events per 1000 person-years; aHR, 1.44; 95% CI, 1.15–1.79; P=0.001). Rates of acute myocardial infarction and stroke were statistically similar.
The study authors add that additional research is needed to further evaluate the risks of insulin use in patients as a second-line treatment for type 2 diabetes in randomized controlled trials.
For more information visit JAMA.org.