Impact of treatment completion, intolerance and adverse events on health system costs in a randomised trial of 4 months rifampin or 9 months isoniazid for latent TB

Abstract

Rationale Treatment for latent tuberculosis infection with isoniazid for 9 months (9INH) has poor completion and serious adverse events, while treatment for 4 months with daily rifampin (4RIF) has significantly higher completion and fewer adverse events. Objectives To compare the health system costs of 4RIF and 9INH. Methods In a randomised trial conducted in five Canadian centres, one Brazilian and one Saudi Arabian centre, consenting subjects were randomised to receive 4RIF or 9INH. Health system costs were estimated from healthcare utilisation including scheduled and unscheduled visits, investigations and drugs. All activities for all subjects were evaluated using financial information from 2007 from the Montreal Chest Institute. Costs were expressed in Canadian dollars. Results Total health system cost per patient allocated to 4RIF was $854 compared with $970 for 9INH (pConclusions The 4RIF regimen was significantly cheaper per patient completing treatment because of better completion and fewer adverse events. RCT registration number NCT00170209.