Drug-eluting stents, or stents that are coated with a drug to prevent narrowing of the vessel, may increase survival rates among people with diabetes who have blocked arteries. The coated stents may also decrease risk of subsequent heart attack and revascularization. Read more.
Drug-eluting stents reduced the risk of revascularization, heart attack, and death in diabetics as compared with bare-metal stents in the largest observational comparison, researchers reported at the American Heart Association’s Scientific Sessions 2008.
The results from The Drug-eluting and Bare Metal Stenting in Patients with Diabetes Mellitus: Results from the Mass-DAC Registry, were presented as a late-breaking clinical trial. The study is simultaneously published in Circulation: Journal of the American Heart Association.
“We actually saw a significant benefit from using drug-eluting stents in this patient population,” said Laura Mauri, M.D., M.Sc., principal investigator of the study and assistant professor of medicine at Brigham and Women’s Hospital and Harvard Medical School in Boston. “First, they significantly reduced the need for repeat procedures which included repeat stenting or bypass surgery. Second, they were associated with lower rates of death and heart attack. So, as a result we can say that these stents appear to be safe in diabetic patients, whose diabetes puts them at higher risk of mortality and heart attack than the general population.”
People with diabetes make up about a third of all patients undergoing percutaneous coronary interventions (PCI) to reopen blocked blood vessels. In PCI with stenting, a balloon-tipped catheter is threaded into the artery to the point of blockage. Then, the balloon is inflated to open the vessel and a mesh metal stent—either bare-metal (BMS) or drug-eluting (DES)—is inserted to keep the channel open. DES are coated with a drug that fights the proliferation of cells that can block the artery (called stenosis).
Researchers identified 5,051 diabetics who underwent PCI at acute-care, non-federal hospitals between April 2003 and September 2004. Diabetic patients at those hospitals were about twice as likely to get DES compared to BMS (66.1 percent vs. 33.9 percent), researchers said.
After three years, people with diabetes who received a drug-eluting stent had a higher survival rate than diabetic patients who received a bare-metal stent. There was a 4.4 percent mortality rate for DES patients compared to 22.2 percent for BMS patients, Mauri said.
After two year, rates of heart attack and revascularization were also lower among patients with diabetes who received drug-eluting stents.
“Diabetic patients represent a large and growing proportion of patients who undergo stenting,” Mauri said. “We know that patients with diabetes have a higher incidence of adverse events following the procedure, including higher rates of restenosis (reblockage), heart attack and death related to heart problems.”
“Previous studies indicated that drug-eluting stents reduce the rate of restenosis, but there has been controversy about their safety because of conflicting evidence from smaller studies.”
Some of those studies found higher mortality associated with DES while others found no safety differences between the two types of stents. This study showed lower mortality and adverse events.