WASHINGTON — With prices continuing to fall, drug-eluting coronary stents have become more cost effective than ever before.
Based on the price of drug-eluting stents, the average number of stents used per patient, and their efficacy at cutting the rate of restenosis, drug-eluting stents are now cost effective in any patient who would have a risk of restenosis of 10% or more if bare-metal stents were used for treatment, David J. Cohen, M.D., said at a meeting sponsored by the Cardiovascular Research Institute of the Washington Hospital Center.
In contrast, based on last year's averages, drug-eluting stents were cost effective whenever the restenosis rate with bare-metal stents was 12% or greater (INTERNAL MEDICINE NEWS, March 15, 2005, p. 58).
The upshot is that drug-eluting stents now make economic sense in wider coronary arteries and in vessels with shorter lesions. It is reasonable from an economic standpoint to use drug-eluting stents in most patients with coronary artery disease, said Dr. Cohen, who is associate director of interventional cardiology at Beth Israel Deaconess Medical Center in Boston.
By early 2005, the two types of drug-eluting stents sold in the United States (sirolimus-eluting and paclitaxel-eluting) cost an average of $2,300 per stent, down from an average of $2,700 last year and $3,100 in 2003. In early 2005, the difference in cost of a drug-eluting coronary stent over a comparable bare-metal stent had dropped to $1,600, down by $300 from the year before.
At Dr. Cohen's center, patients who had drug-eluting coronary stents placed in late 2004 received an average of 1.6 stents each. And the most current data from studies that compared drug-eluting stents with bare-metal stents showed that drug-eluting stents cut the need for target vessel revascularization by about 82%. One additional issue for a cost-effectiveness calculation is that patients who receive drug-eluting stents require daily treatment with clopidogrel for several months, a regimen that costs about $120 per month.
When all of these cost-adding and cost-saving numbers are crunched together, you come up with an estimate indicating that placement of a drug-eluting stent adds no incremental cost when used in patients with an expected restenosis rate with bare-metal stents of at least 10%, he said.
Based on an analysis done by Dr. Cohen and his associates in the late 1990s, virtually all patients with diabetes have a restenosis rate of 10% or greater with bare-metal stents.
The only exceptions are patients with lesions that are less than 30 mm in length that are in coronary arteries that are at least 4.0 mm in diameter. Among patients without diabetes, a restenosis rate of less than 10% with bare-metal stents occurs in all coronary arteries that are 4.0 mm in diameter or greater, regardless of lesion length, and in vessels that are 3.5 mm in diameter or greater if the lesion length is less than 25 mm.