Setting: Eight HIV programs in sub-Saharan Africa.
Objective: To describe the incidence of pulmonary and extrapulmonary tuberculosis before and after the start of combined antiretroviral therapy (ART) and investigate associated risk factors.
Design: Multicohort study. Adults enrolled between January 2006 and September 2008.
Results: A total of 30,134 patients contributed 25,916 person-years of follow-up. The incidence of tuberculosis was 10.5 per 100 person-years during the pre-ART and 5.4 during the ART period. For all types of tuberculosis, incidence was similar in the pre-ART period and initial 3 months of ART but declined over time receiving ART (from 13 per 100 person-years in the first 3 months to 1.5 per 100 person-years after 12 months of therapy). Throughout follow-up, rates of pulmonary tuberculosis remained 2-fold to 3-fold higher than extrapulmonary tuberculosis rates. Smear-negative pulmonary tuberculosis was higher than smear-positive incidence and varied greatly across sites during the pre-ART period. Incidence was lower in rural sites, women, patients without prior history of tuberculosis, body mass index ≥18.5 kg/m², and ≥200 nadir CD4 cells per microliter. Recurrence rate was 1.7 per 100 person-years (95% confidence interval: 1.0 to 2.8).
Conclusions: Our findings show the high burden that tuberculosis represents for HIV programs and highlight the importance of earlier ART start and the need to implement intensified tuberculosis finding, isoniazide prophylaxis, and infection control.