Purpose: To evaluate the cost-effectiveness of drug-eluting stents (DES) compared to bare metal stents (BMS) using data from registries and randomized controlled trials (RCT's).
Method: In most patients undergoing percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI), one or more metal stents are implanted during the procedure to avoid collapsing of coronary arteries. During the last five years, there has been an ongoing debate regarding the relative effectiveness of BMS versus DES (the latter group consisting of either paclitaxel- (PES) or sirolimus-eluting (SES) stents). Meta-analyses performed arrive at conflicting results, partly because they include either RCT’s alone, or additionally patient registries claimed to represent “real-world” data. We developed a Markov model to follow patients for five years after the initial PCI. The model has half year-cycles with the following events: AMI, repeat revascularisation (PCI or CABG), and death. Probabilities of events are based on two Scandinavian registries (SCAAR and WDHR). Effectiveness of different DES compared to BMS was assessed based on either a meta-analysis of RCT’s (Stettler 2009), or data from the SCAAR registry (James 2009).
Result: Analyses based on RCT-data show that PES is cost-saving compared to BMS while SES is not cost-effective at the current Norwegian threshold for cost-effectiveness (approximately $90,000 per life-year gained). When the assessment was based on registries, PES was also the most cost-effective stent type ($14,000 per life year gained), however, the incremental net health benefit (INHB) of PES compared to SES or BMS was less pronounced. Probabilistic sensitivity analyses indicate a 56% probability of PES being the most cost-effective strategy based on effectiveness from RCT’s and a 75% probability based on registry data.
Conclusion: Replacing BMS by DES is cost-effective with a threshold value of $90,000 per QALY regardless whether this health-economic analysis is based on trial- or registry-data.
Candidate for the Lee B. Lusted Student Prize Competition