Crossing borders: Factors affecting differences in cost-effectiveness of smoking cessation interventions between European countries

Abstract

Objectives: Many different factors affect the transferability of cost-effectiveness results between countries. The objective is to quantify the impact of nine potential causes of variation in cost-effectiveness of pharmacological smoking cessation therapies (SCTs) between The Netherlands (reference case), Germany, Sweden, UK, Belgium, and France. Methods: The life-time benefits of smoking cessation were calculated using the Benefits of Smoking Cessation on Outcomes model, following a cohort of smokers making an unaided quit attempt, or using nicotine replacement therapy (NRT), bupropion, or varenicline. We investigated the impact of between-country differences in nine factors - demography, smoking prevalence, mortality, epidemiology and costs of smoking-related diseases, resource use and unit costs of SCTs, utility weights and discount rates - on the incremental net monetary benefit (INMB), using a willingness-to-pay (WTP) of €20,000 per quality adjusted life year (QALY). Results: The INMB of 1000 quit attempts with NRT versus unaided, varies from €0.39 million (Germany) to €1.47 million (France). The differences between the countries were primarily due to differences in discount rates, causing the INMB to change between -65% to +62%, incidence and mortality rates (epidemiology) of smoking-related diseases (-43% to +35%) and utility weights. Impact also depended on the WTP for a QALY and time horizon: at a low WTP or a short time horizon, the resource use and unit costs of SCTs had the highest impact on INMB. Conclusions: Although all INMBs were positive, there were significant differences across countries. These were primarily related to choice of discount rate and epidemiology of diseases. © 2009, International Society for Pharmacoeconomics and Outcomes Research (ISPOR).