Tuberculosis associated mortality in a prospective cohort in Sub Saharan Africa: Association with HIV and antiretroviral therapy

Abstract

Objective: Nine out of ten tuberculosis deaths occur in tuberculosis-burdened countries, particularly Sub Saharan Africa. In these setting mortality has not been fully described. We describe the magnitude and pattern of TB mortality in Tanzania.

Methods: A multicenter prospective cohort study was conducted among HIV infected and uninfected pulmonary tuberculosis patients from time of anti-TB treatment initiation to completion. Patients were censored at the time of treatment completion, or at their last visit for those who did not complete TB treatment. Kaplan-Meier curves were used to estimate time to death; cox proportional hazards model was used to examine risk factors for mortality.

Results: A total of 58 deaths out of 1696 patients (3.4%) occurred, two thirds (n=39) during the first two months of treatment. Compared to HIV un-infected TB patients, mortality risk for TB/HIV co-infected patients was least when antiretroviral therapy (ART) was initiated after 14 days of anti-TB (RR=3.55; 95% CI: 1.44, 8.73 p<0.0001) and highest when ART was initiated 90 days or less prior to anti-TB and within the first 14 days of anti-TB therapy (RR=10; 95% CI: 3.28, 30.54; p<0.0001).

Conclusion: Meticulously planned and supervised antiretroviral therapy reduces mortality among TB/HIV patients. Among patients with TB/HIV naïve of ART, withholding ART until the third week of anti-tuberculosis therapy will likely reduce TB mortality in Tanzania. Patients on ART and later develop tuberculosis should be closely monitored.

Keywords: ART; ARV; Antiretroviral therapy; HIV; TB; TB/HIV; death; survival; treatment outcome.