MONDAY, Oct. 3, 2005 (HealthDay News) -- Drug-coated stents are better for diabetic patients than the older bare metal tubes inserted to keep blood flowing after the artery-opening procedure called angioplasty, Spanish cardiologists report.
The finding is no great surprise, since a number of studies in the United States and other countries have shown the advantage of drug-eluting stents. But the result is important because "overall, the outcomes of diabetic patients after angioplasty are poorer than those of nondiabetics," said study author Dr. Manel Sabate, a consultant in cardiology at San Carlos University Hospital in Madrid. His report appears in the Oct. 4 issue of Circulation.
The study included 160 people with diabetes, half of whom had bare metal stents inserted after angioplasty. The other half got stents coated with the drug sirolimus.
In the nine months following the procedure, arteries of patients given drug-coated stents narrowed by an average of only 0.06 millimeters, compared to 0.47 millimeters for the arteries of those given bare-metal stents, the researchers reported.
That difference had a very practical benefit. While 29 of the 80 patients who got the bare metal stents died or had adverse cardiac events such as heart attacks, only eight of the 80 who got coated stents had such outcomes. Only five of those who got coated stents needed repeat angioplasty, compared to 25 of those getting the bare metal stents.
During hospitalization, three standard-stent patients suffered heart attacks, and one died of a cardiac rupture. There were no major cardiac events in the drug-stent group.
"Conventional stent implantation still exhibits a high incidence of major cardiac events in the diabetic population, especially in those requiring insulin," Sabate said. "With the use of conventional stents, the expected re-narrowing rate may vary from 30 percent to 60 percent in diabetic patients vs. 15 percent to 30 percent in nondiabetic patients."
The researchers said they will continue to monitor the patients for the next two years to evaluate the long-term value of drug-eluting stents.
Sirolimus, the drug used in the Spanish study, is one of two medications available to coat stents. Two European studies recently found an advantage of sirolimus over the other drug, paclitaxel. The benefit in terms of keeping arteries open, preventing heart attacks and keeping patients alive was greatest for people at highest risk -- a group that includes diabetics.
"It's an important study because it was specifically designed to look at stents in patients with diabetes, rather than drawing on a subgroup in a larger trial," said Dr. Sidney Smith, a professor of medicine at the University of North Carolina and a spokesman for the American Heart Association
The study is "good news for patients with diabetes," Smith said. "It shows that sirolimus-coated stents improve treatment in both insulin-treated and noninsulin-treated diabetics."
The only flaw of the trial was that it began before the latest generation of stents became available, he said. "The trial did not compare the newer cobalt chromium stents," Smith said. "It will be important to evaluate them."
You can learn more about stents from the American Heart Association.