Cost effectiveness of drug eluting coronary artery stenting in a UK setting: cost-utility study

Objective: To assess the cost effectiveness of drug eluting stents (DES) compared with conventional stents for treatment of symptomatic coronary artery disease in the UK. Design: Cost-utility analysis of audit based patient subgroups by means of a simple economic model. Setting: Tertiary care. Participants: 12 month audit data for 2884 patients receiving percutaneous coronary intervention with stenting at the Cardiothoracic Centre Liverpool between January 2000 and December 2002. Main outcome measures: Risk of repeat revascularisation within 12 months of index procedure and reduction in risk from use of DES. Economic modelling was used to estimate the cost-utility ratio and threshold price premium. Results: Four factors were identified for patients undergoing elective surgery (n = 1951) and two for nonelective surgery (n = 933) to predict risk of repeat revascularisation within 12 months. Most patients fell within the subgroup with lowest risk (57% of the elective surgery group with 5.6% risk and 91% of the nonelective surgery group with 9.9% risk). Modelled cost-utility ratios were acceptable for only one group of high risk patients undergoing non-elective surgery (only one patient in audit data). Restricting the number of DES for each patient improved results marginally: 4% of stents could then be drug eluting on economic grounds. The threshold price premium justifying 90% substitution of conventional stents was estimated to be 112Pounds (US$212, 162Euros) (sirolimus stents) or 89Pounds (US$ 167, 130Euros) (paclitaxel stents). Conclusions: At current UK prices, DES are not cost effective compared with conventional stents except for a small minority of patients. Although the technology is clearly effective, general substitution is not justified unless the price premium falls substantially.