Abstract 6230: Willingness-to-Pay to Avoid Restenosis Following Percutaneous Coronary Intervention in Canadian Patients; A Contingent Valuation
Background: Percutaneous coronary interventions (PCI) remain limited by the risk of restenosis. Traditional cost-effectiveness analysis may minimize the impact of restenosis from the patient’s perspective. Contingent valuation may provide more valuable insights on this burden.
Methods: We used a contingent valuation approach to assess the willingness-to-pay (WTP) for a hypothetical treatment which could eliminate the risk of restenosis among 270 patients undergoing cardiac catheterization with ad hoc PCI in a large Canadian tertiary centre. Patients’ were given a scenario describing a 10 or 20% probability of restenosis in the year following the procedure, which would lead to repeat PCI or more rarely bypass surgery, without any increase in mortality. Using a close-ended question, patients were asked their out-of-pocket WTP for a hypothetical treatment which would eliminate that risk. Six different “take-it-or-leave-it” bids ($500, $1000, $1500, $2000, $2500, and $3000) and both risk levels were randomly varied creating 12 sub-samples of scenarios. Patients were asked if they were willing to pay the proposed amount and an additional $500 if they agreed. Only patients willing to pay both amounts were considered willing to pay the initial bid. Patients also answered an SF-36 questionnaire. WTP responses were analyzed by non-parametric methods. Multiple logistic regression models were generated to identify factors associated with WTP.
Results: The median WTP for a technology which would eliminate restenosis was estimated at $2802. Each increase of $1000 of the bid was independently associated with a lower WTP (odds ratio [OR] =0.63, 95% confidence interval [CI] 0.45–0.88). A higher gross family income (OR=2.33, 95%CI 1.12–4.84) and better mental health, measured with the SF-36 mental component scale (MCS) (OR=1.02 for each MCS point, 95%CI 1.00–1.03), were both independently associated with a higher WTP.
Conclusions: Although non-life saving, the potential to avoid restenosis has considerable value for patients undergoing PCI, supporting the use of drug-eluting stents over bare metal stents. In addition to the capacity to pay, better mental health was also associated with increased WTP.