Cost-effectiveness of tuberculosis screening and isoniazid treatment in the TB/HIV in Rio (THRio) Study.
OBJECTIVE
To estimate the incremental cost-effectiveness of tuberculosis (TB) screening and isoniazid preventive therapy (IPT) among human immunodeficiency virus (HIV) infected adults in Rio de Janeiro, Brazil.


DESIGN
We used decision analysis, populated by data from a cluster-randomized trial, to project the costs (in 2010 USD) and effectiveness (in disability-adjusted life years [DALYs] averted) of training health care workers to implement the tuberculin skin test (TST), followed by IPT for TST-positive patients with no evidence of active TB. This intervention was compared to a baseline of usual care. We used time horizons of 1 year for the intervention and 20 years for disease outcomes, with all future DALYs and medical costs discounted at 3% per year.


RESULTS
Providing this intervention to 100 people would avert 1.14 discounted DALYs (1.57 undiscounted DALYs). The median estimated incremental cost-effectiveness ratio was $2273 (IQR $1779-$3135) per DALY averted, less than Brazil's 2010 per capita gross domestic product (GDP) of $11,700. Results were most sensitive to the cost of providing the training.


CONCLUSION
Training health care workers to screen HIV-infected adults with TST and provide IPT to those with latent tuberculous infection can be considered cost-effective relative to the Brazilian GDP per capita.