Opportunities for tuberculosis elimination in the Canadian Arctic: cost-effectiveness of community-wide screening in a remote Arctic community.

Background: In response to a tuberculosis (TB) outbreak in the remote community of Qikiqtarjuaq Nunavut, Canada, community leaders and the territorial government initiated community-wide screening (CWS) for tuberculosis, an expensive undertaking given the high cost of providing medical services in the Canadian arctic. Our study aim was to assess the cost-effectiveness of the Qikiqtarjuaq CWS. Methods: We developed a hybrid decision analysis and Markov model to replicate the experience and extrapolate CWS outcomes over a 20-year time horizon. Following a hypothetical cohort with patient characteristics reflecting the demographic and testing data available from the CWS, the model compared a one-time CWS intervention with the reference case of 'no community-wide screening'. Findings: CWS resulted in improved health gains through prevention of active tuberculosis cases compared with no CWS. It also resulted in increased costs (measured in Canadian dollars), with a very low estimated incremental cost-effectiveness ratio (ICER) of $25.10 (95% URs: cost savings-$15,874) per additional quality adjusted life year (QALY) gained compared with current standard of care approach (no CWS). Community-wide screening in this context would be considered highly cost-effective in this setting. In probabilistic sensitivity analysis, we found >99% of iterations were cost-effective at a willingness to pay threshold of $50,000/QALY gained. Interpretation: While costly, coordinated and intensive community-wide tuberculosis screening activities are highly cost-effective in remote arctic communities when utilized in an outbreak context. Funding: Government of Nunavut.