Sputum induction for tuberculosis diagnosis in an Arctic setting: a cost comparison

Tuberculosis (TB) incidence was 234 per 100 000 in Nunavut, Canada, in 2012. Until recently, some individuals seen in local clinics for presumed TB required costly air evacuation to Southern Canada (Ottawa) for investigation if they were unable to produce sputum spontaneously.

To estimate the cost per individual evaluated for TB, associated with the establishment of a sputum induction programme in Iqaluit, Nunavut, Canada.

A decision analysis model compared the total cost per individual for two strategies: 1) initial investigation in Iqaluit, with transport to Ottawa for those requiring sputum induction; and 2) sputum induction at the hospital in Iqaluit, with further investigation in Ottawa only if needed. The model simulated diagnostic and treatment paths from the initial clinic visit to completion of TB investigation or treatment (when applicable).

The estimated cost per person evaluated for TB with sputum induction in 1) Ottawa vs. 2) Iqaluit was CAD4798 (95% uncertainty range 2923-6650) vs. CAD2479 (1206-4256), respectively. Total costs were influenced by underlying TB prevalence, but local sputum induction consistently yielded cost savings.

Providing sputum induction in a high-incidence Arctic community such as Iqaluit is projected to generate substantial cost savings in the investigation and management of individuals with presumed TB.