Predictors of tuberculosis in first 6 months after initiation of antiretroviral therapy: a case-control study

SETTING: In Africa, 10% of human immunodeficiency virus (HIV) infected adults starting antiretroviral therapy (ART) die within the first year, and tuberculosis (TB) is the leading cause of death.OBJECTIVE: To investigate the predictors of ART-associated TB at an adult HIV clinic in Tanzania.DESIGN: In this nested case-control study, adults starting ART were screened for TB according to the World Health Organization protocol. Those not diagnosed with TB were observed for 6 months. Patients diagnosed with TB were defined as cases, and controls were selected from among the patients who did not develop TB using incidence density matching.RESULTS: Among the 2514 HIV-positive adults in our cohort, 72 (3%) were diagnosed with TB during the first 6 months of ART. By multivariate analysis, baseline characteristics predictive of TB were cough, fever and night sweats; 76% (55/72) of the cases had at least one of these symptoms at the time of starting ART.CONCLUSION: Overall, 75% of the patients who developed TB during the first 6 months of ART had TB symptoms at the time of starting ART. Improved TB diagnostics and/or better strategies for empirical anti-tuberculosis treatment are needed for patients with symptoms of TB at ART initiation.