Patients who receive a drug-eluting stent (DES) are less likely to die, have a heart attack, or require costly follow-up surgery than those who receive a bare-metal stent (BMS), according to researchers from the University of Pennsylvania School of Medicine (Philadelphia).
The findings published yesterday in the Journal of the American College of Cardiology showed a "clear, lifesaving benefit of drug-eluting stents compared to bare metal stents" among elderly patients in the two years following placement of the stent, according to the researchers.
"This might be a hidden nugget of goodness that could not be detected in clinical trials," said Peter Groeneveld, MD, an assistant professor in Penns division of general internal medicine. "There is a distinct possibility that drug-eluting stents not only reduce the need for future cardiac procedures, but also save lives."
Groeneveld and his colleagues studied Medicare data to identify about 72,000 patients who received a DES during a nine-month period in 2003, the year that the Cypher sirolimus-eluting stent from Cordis (Miami Lakes, Florida) became the first DES cleared for use in the U.S. Overall, the findings showed "an association" between drug-eluting stents and improved survival, Groenevald told Medical Device Daily. At 90 days, one year and two years, patients with a drug-eluting stent were less likely to die, according to the findings.
"A lot of the data that has been published on drug-eluting stents has been from the clinical trials, which dont represent real-world medicine because they are done in very scientifically-controlled environments, typically at leading hospitals," Groeneveld said, calling the care that clinical trial patients receive "gold-plated."
The fact that nobody died is one of the shortcomings of the clinical trial data, he said, because it makes it difficult to know the true performance of the devices in a real-world setting.
"Our intention was to kind of take a look from the perspective of humdrum medical care doled out at hundreds of hospitals across the country," Groeneveld said. "The bottom line is a provocative and I mean it to be provocative look at whether we truly know the performance of drug-eluting stents vs. bare-metal stents in the real world because sometimes clinical trials dont give the complete picture."
Since FDA cleared Cordis Cypher stent in 2003, the DES market has been on a roller-coaster ride, characterized by data questioning the safety and effectiveness of the devices compared to bare-metal stents. Those ups and downs make it tough to predict what impact Groenevelds research will have on the use of the drug-coated devices compared to bare-metal stents.
"Its hard to know what influences surgeons decisions," Groeneveld said. "From my own observation its been quite irrational; for a while almost nobody was using drug-eluting stents" in reaction to worrisome data that has been published.
"We see this kind of behavior in the stock market all the time; Im not sure its rational [in the medical arena]," he said.
In a separate study, expected to appear in the June issue of the American Heart Journal, Groeneveld found that drug-eluting stents offer cost savings during the first year after placement. Although the initial cost of the device averaging $16,000 outpaces that of a bare-metal stent, which costs about $14,000, the Penn researchers found that among patients with the drug-coated stents, 12% of those studied needed additional stents placed in the first year, compared to 15% of patients who received bare-metal stents.
Few patients in either arm required bypass surgery in the first year following stent placement, but those who received bare-metal stents were twice as likely to need the procedure, leading to an additional cost savings of $714 per DES patient. Overall, researchers found that patients with a DES each saved an average of $1,350 worth of follow-up care during the year, which projects to a total savings of roughly $100 million dollars among the 72,000 DES patients studied.
"Its clear that [DES use] reduces the number of procedures downstream, which is what [the companies] kind of promised to do," Groeneveld said.
The researchers noted that future studies should focus on how drug therapies including clopidogrel and cholesterol-reducing statin drugs may play a role in outcomes and costs for both types of stent patients. Because recent evidence shows that clopidogrel therapy aimed at reducing the risk of blood clots following stent placement is an essential step for reducing "late" DES complications or failure, he theorizes that clinical outcomes for DES patients might be boosted even further when patients follow an appropriate long-term drug regimen.
The research was supported by an unrestricted grant from the Institute for Health Technology Studies (InHealth; Washington), a nonprofit organization that researches the social and economic impact of medical technology and adds evidence for evidence-based policy.