Cost-effectiveness of drug-eluting stents including the economic impact of late stent thrombosis

Abstract

Recent studies examining the effectiveness of drug-eluting stents (DES) have found that the use of DES is associated with a significant increase in the incidence of late stent thrombosis (LST). Previous cost-effectiveness analyses of DES have not accounted for the costs associated with LST. In this study, published research was reviewed to identify studies that compared the cost-effectiveness of DES with that of bare-metal stents and to identify the incidence of LST. Probable costs were assigned to LST-related myocardial infarction and death on the basis of the treatment costs for these outcomes. These costs as well as those of extended clopidogrel therapy were then incorporated into the Sirolimus-Eluting Balloon Expandable Stent in the Treatment of Patients With De Novo Native Coronary Artery Lesions (SIRIUS) and TAXUS-IV cost-effectiveness data. This review found that the incidence of LST ranged from 0.2% to 0.7%. Assuming a base case LST incidence of 0.5%, a cost per death of $20,000, a cost per myocardial infarction of $20,000, and a cost of an additional 2 years of clopidogrel therapy of $2,428 per patient, the costs per revascularization avoided were $15,056 for the SIRIUS trial and $25,210 for the TAXUS-IV trial. The costs per quality-adjusted life-year gained were $250,935 and $257,591, respectively. Sensitivity analyses revealed that the costs per revascularization avoided varied from $14,618 to $15,830 for the SIRIUS trial and from $24,540 to $26,396 for the TAXUS-IV trial. Similarly, the cost per quality-adjusted life-year gained varied from $243,638 to $263,840 for the SIRIUS trial and from $250,739 to $269,708 for the TAXUS-IV trial. In conclusion, LST-related adverse events and the need for extended clopidogrel therapy substantially increase the costs associated with the implementation of DES. The inclusion of these costs renders the widespread use of DES not cost effective in the United States in terms of cost per quality-adjusted life-year gained and cost per revascularization avoided.