Author’s note: the studies cited in this article were created by and for Boston Scientific Corp. for its drug-eluting stent program.

The era of drug-eluting stents has arrived. There is no doubt that drug-eluting stenting (DES) represents a dramatic new technology that has the potential to make a major impact on the treatment of coronary artery disease. Clinical trial results have shown target lesion revascularization (TLR) rates as low as 3% at nine months, and in-segment restenosis of rates as low as 7.9% at nine months (N Engl J Med 2004;350:221-231).

To health economists, these important clinical results have equally important economic implications and may provide a useful context for considering the adoption and use of a medical procedure.

DES FROM A HEALTH ECONOMICS POLICY PERSPECTIVETo understand the economics of DES, it is necessary first to examine the economics of coronary restenosis for non-drug-eluting percutaneous coronary interventions (PCIs). Two studies using health insurance claims data examine the "real-world" clinical and economic burden of restenosis in the elderly and in a relatively younger population enrolled in managed care plans. These analyses are helpful in estimating total potential cost offsets to payers due to DES adoption.

The Economics of Restenosis in the Medicare Program. The first study,¹ "Clinical and Economic Burden of Coronary Restenosis in the Medicare Program," presented at the Fourth Scientific Forum on Quality of Care and Outcomes Research in Cardiovascular Disease and Stroke (October 2002, updated January 2004), uses Medicare claims data to: 1) determine the clinical and economic burden (such as added cost) of coronary restenosis in the Medicare population; and 2) show the potential that DES utilization offers for cost reduction. Extrapolation of study results suggests annual Medicare expenditures for repeat revascularization treatment of more than $730 million; the study also suggests that new technologies such as DES that reduce repeat procedure rates after PCI may be helpful in reducing costs. This study can be viewed and downloaded in its entirety at http://www.managedhealthcareexecutive.com/mhe/article/articleDetail.jsp?id=100503

The Economics of Restenosis in a Managed Care Population. The other study,² "The Clinical and Economic Burden of Coronary Restenosis in a Managed Care Population," presented at Transcatheter Cardiovascular Therapeutics (TCT) conference in September 2003, also demonstrates the clinical and economic burden of coronary restenosis in patients treated with conventional PCI.

However, the analysis uses managed care claims data to examine these issues from a U.S. managed care payer perspective. The study found additional MCO costs of $24,955 per restenosis patient; it also found DES cost offsets of $1,559 to $3,118 per PCI patient when restenosis is reduced by either 50% or 100%. This study can be viewed and downloaded in its entirety at http://www.managedhealthcareexecutive.com/mhe/article/articleDetail.jsp?id=100516

In sum, both these analyses show the significant costs that coronary restenosis imposes on society.

• The Impact of Diabetes. Restenosis in the general population is costly; in the diabetic population, even more so. A study,^{3 "} The Impact of Diabetes on Clinical and Economic Outcomes of PCI in the Elderly," presented at the American College of Cardiology 52nd Annual Scientific Session (March-April 2003; updated January 2004), 1) examines the impact of diabetes mellitus on clinical and economic outcomes after PCI in an unselected population of elderly patients; and 2) demonstrates the potential for significant cost savings if DES is proven safe and effective in reducing restenosis in diabetics.