Tuberculosis treatment survival of HIV positive TB patients on directly observed treatment short-course in Southern Ethiopia: A retrospective cohort study

BACKGROUND: Tuberculosis (TB) and HIV co-infection remains a major public health problem. In spite of different initiatives implemented to tackle the disease, many countries have not reached TB control targets. One of the major attributing reasons for this failure is infection with HIV. This study aims to determine the effect of HIV infection on the survival of TB patients. FINDINGS: A retrospective cohort study was employed to compare the survival between HIV positive and HIV negative TB patients (370 each) during an eight month directly observed treatment short-course (DOTS) period. TB patient’s HIV status was considered as an exposure and follow up time until death was taken as an outcome. All patients with TB treatment outcomes other than death were censored, and death was considered as failure. Cox proportional hazard regression model was used to determine the hazard ratio (HR) of death for each main baseline predictor. TB/HIV co-infected patients were more likely to die; adjusted Hazard Rate (AHR) =1.6, 95%CI (1.01, 2.6) during the DOTS period. This risk was statistically higher among HIV patients during the continuation phase (p=0.0003), as a result HIV positive TB patients had shorter survival (Log rank test= 6.90, df= 2, p= 0.008). The adjusted survival probability was lower in HIV positive TB patients (< 15%) than HIV negative TB patients (> 85%) at the end of the DOTS period (8(th) month). CONCLUSION: TB treatment survival was substantially lower in HIV infected TB patients, especially during the continuation phase. Targeted and comprehensive management of TB/HIV with a strict follow up should be considered through the entire TB treatment period.