Mortality among pulmonary tuberculosis and HIV-1 co-infected Nigerian children being treated for pulmonary tuberculosis and on antiretroviral therapy: a retrospective cohort study

Background: Mortality data, including the risk factors for mortality in HIV-infected children with pulmonary TB (PTB) being treated for PTB and who are on antiretroviral therapy (ART), are scarce in Nigeria. We determined the mortality rate and risk factors for mortality among such children, at the pediatric HIV clinic of the Jos University Teaching Hospital (JUTH) in Jos, Nigeria.

Methods: We performed a retrospective cohort study on 260 PTB-HIV-1 co-infected children, aged 2 months to 13 years, being treated for PTB and on ART from July 2005 to March 2013. The mortality rate and associated risk factors were determined using multivariate Cox proportional hazards modelling.

Results: The mortality rate for the study cohort was 1.4 per 100 child-years of follow-up. Median follow-up time was 5.2 years (IQR, 3.5-6.0 years) with total study time being 1159 child-years. The median age of those who died was lower than that of survivors, 1.9 years (IQR, 0.6-3.6 years) versus 3.8 years (IQR, 1.8-6.0 years), p=0.005). The majority of the deaths occurred in males (13, 81.2%), those <5 years of age (14, 87.4%) and those who had severe immunosuppression (11, 68.8%). Risk factors for death were age (with the risk of dying decreasing by 25% for every 1 year increase in age, adjusted hazard ratio (AHR)=0.75 [0.58-0.98], p=0.032), male gender (AHR=3.80 [1.07-13.5], p=0.039) and severe immunosuppression (AHR=3.35 [1.16-9.66], p=0.025).

Conclusion: In our clinic setting, mortality among our PTB-HIV co-infected children being treated for PTB and on ART was low. However, those presenting with severe immunosuppression and who are males and very young, should be monitored more closely during follow-up in order to further reduce mortality.