On TB Treatment Survival of HIV Positive TB Patients on Short Course Chemotherapy in Southern Ethiopia: A Retrospective Cohort Study

Background: In contrast to, many initiatives implemented to tackle tuberculosis, many countries have not so far reached the targets set by WHO. The main reason mentioned so far was the impact of HIV infection. Therefore, this study aims to determine the impact of HIV/AIDs on the survival of TB patients on Directly Observed Therapy.

Methods: A retrospective cohort study design was employed to compare the on TB treatment survival between the exposed; HIV positive (n=370) and non exposed; HIV negative TB patients (n=370) who were through the short course DOTs in Hawassa Health Center from 2006-2010. Patient’s HIV status during the diagnosis of TB or initiation of DOTs was considered as an exposure and time until on TB treatment death was considered as an outcome variable. All patients with TB treatment outcomes other than death were censored, and death was considered as failure.

Results: The risk of death was statistically higher among TB/HIV co infected patients; AHR=1.6, 95%CI (1.01-2.6) during the course of DOTs. This risk was not different between the exposed and non-exposed during the intensive phase (P=0.15), but significantly higher in the exposed during continuation phase (p=0.0003). Regarding survival of TB patients, the survival rate was lower for the exposed patients (Log rank test= 6.90, df= 2, P= 0.008).When adjusted for covariates, the survival probability was <15% for the exposed but >85% in non-exposed TB patients at the end of DOTs period (8^th month). The independent predictors of death, while on treatment were age, weight and HIV infection.

Conclusion: On TB treatment survival was substantially lower in HIV infected TB patients especially during continuation phase due to an increased death. Therefore targeted and comprehensive management of TB/HIV with a strict follow up should be considered throughout the whole course of DOTS in this group of patients.