Directly observed therapy and risk of unfavourable tuberculosis treatment outcomes among an international cohort of people living with HIV in low- and middle-income countries

Abstract

Introduction: Identification of persons living with human immunodeficiency virus (HIV)-associated tuberculosis (TB) at increased risk for unfavourable TB outcomes would inform efforts to improve such outcomes. We sought to identify factors associated with a decreased risk of unfavourable TB treatment outcomes among people living with HIV-infection (PLHIV) in low- and middle-income countries (LMIC), with a specific focus on directly observed therapy (DOT) compared with self-administered therapy (SAT) during the continuation phase of anti-TB therapy.

Methods: We conducted a retrospective cohort study among adults diagnosed with HIV-associated TB in Africa, Asia and the Americas from 2012 to 2013; data were collected from 2012 to 2016. Unfavourable TB treatment outcomes (death during TB treatment, and TB treatment failure or recurrence) were defined according to World Health Organization criteria. Receipt of DOT was obtained at the site level and defined as ≥5 days of DOT per week. The person administering DOT and treatment location varied by site. Lack of receipt of DOT was defined as SAT. Multivariable logistic regression estimated the adjusted odds of unfavourable TB treatment outcomes.

Results: Among 1862 adults with HIV-associated TB included, 252 (13.5%) had unfavourable TB outcomes (226 deaths, 26 recurrences/failures). Overall, 1825 (98%) received DOT in the intensive phase and 1617 (87%) received DOT in the continuation phase. DOT in the continuation phase was not significantly associated with unfavourable TB outcomes (aOR 1.43, 95% CI 0.86 to 2.38) compared to SAT. Body mass index (BMI) change during anti-TB treatment (per 2 units increase, aOR 0.74, 95% CI 0.68 to 0.82) and CD4⁺ count at TB diagnosis (200 vs. 50 cells/µL, aOR 0.54, 95% CI 0.39 to 0.73) were both independently associated with decreased odds of unfavourable TB treatment outcomes.

Conclusions: In this large, international cohort of people living with HIV-associated TB in LMIC who received intensive phase DOT, DOT during the continuation phase of anti-TB therapy was not associated with a decreased odds of unfavourable TB treatment outcomes compared to SAT. Randomized trials evaluating the effect of continuation-phase DOT on TB outcomes among PLHIV are needed.

Keywords: antiretroviral therapy; body mass index; directly observed therapy; human immunodeficiency virus infection; tuberculosis.