Peripheral Artery Stents Cut Amputation Rates, Costs

HOLLYWOOD, FLA. -- A stent-based, endovascular approach for treating peripheral arterial disease led to reduced medical costs compared with treatment by bypass surgery or with angioplasty alone, based on analysis of data from more than 30,000 Medicare beneficiaries during 1999-2005.

Treatment of peripheral arterial disease (PAD) with a stent led to a significantly reduced risk for subsequent amputation compared with angioplasty alone or bypass surgery, Michael R. Jaff, D.O., reported at ISET 2008, an international symposium on endovascular therapy.

These findings support the concept that endovascular therapy for PAD that includes stenting "is more effective in reducing risk of recurrent interventions or amputation than a purely percutaneous transluminal angioplasty-based endovascular intervention," he said in an interview.

He stressed that his study was a retrospective analysis of a 5% sample of Medicare data. When assessing the relative efficacy of peripheral angioplasty alone compared with stenting of peripheral arteries, "I put way more emphasis" on the results from prospective, randomized, controlled studies.

Results from an Austrian study of 104 patients, showed that treatment with a stent in the superficial femoral artery led to significantly less restenosis than did angioplasty alone after 1 year of follow-up (N. Engl. J. Med. 2006;354:1879-88).

And at the same meeting, Dr. Barry T. Katzen presented 1-year follow-up results from the Randomized Study Comparing the Edwards Self-Expanding LifeStent vs. Angioplasty Alone in Lesions Involving the SFA and/or the Proximal Popliteal Artery (RESILIENT) trial. The 134 patients treated with angioplasty plus a LifeStent had a primary patency rate of 80%, a freedom from target-lesion revascularization rate of 87%, and a clinical success rate of 72%. These outcomes for all three measures were significantly better than the 38%, 46%, and 34% rates, respectively, in 72 patients treated with angioplasty alone, said Dr. Katzen, medical director of the Baptist Cardiac and Vascular Institute in Miami.

Findings in Dr. Jaff's new study also showed an "inexorable" increase in the prevalence of PAD during the 7-year period studied. PAD prevalence rose from 8.2% in 1999 to 9.0% in 2002 and 9.5% in 2005. The increase was even sharper in patients older than 75, rising from 12.7% in 1999 to 14.5% in 2005, said Dr. Jaff of Massachusetts General Hospital, Boston.

These findings are "potentially major," he said. "As the population continues to age, with increasing prevalence of diabetes and obesity among Medicare eligible patients, more patients with PAD will be presenting to their physicians. Therefore, effective therapy for these patients must also be cost effective, as the implications to the U.S. health care economy will be at least as dramatic as is the care of patients with coronary artery disease."

Dr. Jaff's study used data collected during 1999-2005 in the Medicare Standard Analytic File, a random sample of 5% of Medicare beneficiaries. The study assessed outcomes and costs during the first calendar quarter in which patients were treated for PAD and all subsequent quarters. Costs were adjusted to 2005 dollars.

The risk of amputation was analyzed in a total of 38,663 patients. In a model that adjusted for age, gender, ethnicity, renal function, and PAD risk factors, the roughly 10,000 patients who were treated with either a stent alone or with a stent in combination with angioplasty or atherectomy had about half the rate of limb amputations as the more than 20,000 patients treated with angioplasty alone. But the amputation rate among more than 8,000 patients treated with bypass surgery was about three times the rate in the angioplasty only patients, Dr. Jaff said.

PAD-related costs during the study period averaged about $20,000 per patient treated with bypass, and about $12,000 per patient treated with angioplasty only. In contrast, PAD-related costs were roughly $6,000 per patient treated with a stent only or with a stent plus angioplasty or atherectomy. Total medical costs were an average of about 5% higher per patient for all patients with PAD compared with all patients with coronary artery disease. Possible explanations are that PAD patients often require more frequent care, treatment of PAD is less durable, and PAD is usually more diffuse than coronary disease, Dr. Jaff said.

Dr. Jaff and Dr. Katzen have financial relationships with several device manufacturers. Dr. Katzen is a consultant for Edwards Lifesciences, maker of LifeStent