Treatment costs of directly observed therapy and traditional therapy for Mycobacterium tuberculosis: a comparative analysis

OBJECTIVE: Treatment of tuberculosis is a time-consuming and expensive proc ess, often complicated by patient non-adherence. Directly observed therapy (DOT), an out-patient management strategy designed to ensure adherence, is not widely used because it is perceived to be too expensive. This study com pared costs of tuberculosis treatment in DOT to the same factors in traditi onal therapy. DESIGN: A retrospective economic evaluation of 659 tuberculosis cases was r eported to a major metropolitan county public health department between 198 0 and 1994, Out-patient costs, in-patient costs and the cost impact of rela pse and acquired resistance were estimated in 1995 dollars. RESULTS: Treatment costs were lower with DOT: $15 670 per case for in-patie nt care and $700 per case for out-patient care (P < 0.001). These cost diff erences resulted from shorter therapy duration (334 vs 550 days), fewer pat ient hospitalizations (58 vs 75%) and. shorter hospital stays (26 vs 55 day s per hospitalized patient). Relapse or acquired resistance occurred in 10. 9% of patients and accounted for 35.7% of cost with traditional therapy, as compared to 1.2% of patients and 6.0% of cost with observed therapy. CONCLUSIONS: Directly observed therapy is less costly than traditional ther apy.