Cost-effectiveness of tuberculosis diagnostic strategies to reduce early mortality among persons with advanced HIV infection initiating antiretroviral therapy.

ABSTRACT

BACKGROUND: In sub-Saharan Africa, patients with advanced HIV experience high mortality during the first few months of antiretroviral therapy (ART), largely attributable to tuberculosis (TB). We evaluated the cost-effectiveness of TB diagnostic strategies to reduce this early mortality. METHODS: We developed a decision analytic model to estimate the incremental cost, deaths averted, and cost-effectiveness of 3 TB diagnostic algorithms. The model base case represents current practice (symptoms screening, sputum smear, and chest radiography) in many resource-limited countries in sub-Saharan Africa. We compared the current practice with World Health Organization (WHO)-recommended practice with culture and WHO-recommended practice with the Xpert mycobacterium tuberculosis and resistance to rifampicin test and considered relevant medical costs from a health system perspective using the timeframe of the first 6 months of ART. We conducted univariate and probabilistic sensitivity analyses on all parameters in the model. RESULTS: When considering TB diagnosis and treatment and ART costs, the cost per patient was $850 for current practice, $809 for the algorithm with Xpert test, and $879 for the algorithm with culture. Our results showed that both WHO-recommended algorithms avert more deaths among TB cases than does the current practice. The algorithm with Xpert test was least costly at reducing early mortality compared with the current practice. Sensitivity analyses indicated that cost-effectiveness findings were stable. CONCLUSIONS: Our analysis showed that culture or Xpert were cost-effective at reducing early mortality during the first 6 months of ART compared with the current practice. Thus, our findings provide support for ongoing efforts to expand TB diagnostic capacity.