A Description of Mortality Associated with IPT plus ART Compared to ART Alone among HIV-Infected Individuals in Addis Ababa, Ethiopia: A Cohort Study

Abstract

Background: Tuberculosis (TB) is the most common human immunodeficiency virus (HIV) associated opportunistic infection. It is the leading cause of death in HIV-infected individuals in sub-Saharan Africa. Anti-retroviral therapy (ART) and isoniazid preventive therapy (IPT) are the two useful TB preventative strategies available to reduce TB among people living with HIV (PLHIV). Therefore, the aim of this study is to compare mortality associated with IPT taken together with ART, as well as ART alone, among PLHIV.

Methods: A retrospective cohort study was undertaken at Tikur Anbessa Specialized Hospital (TASH) and Zewditu Memorial Hospital (ZMH) on 185 patients receiving IPT (6 months) plus ART and 557 patients receiving ART alone. Mortality rates (MR) per 100 person-years (PYs) were used to compare mortality rates amongst the groups. Time-to-death and survival probabilities of the patients were determined using the Kaplan Meier Method. The Cox Proportional Hazard Model was employed to estimate the effect of IPT plus ART on survival of PLHIV.

Results: The mortality cases noted in patients treated by IPT plus ART versus ART alone were 18 (4.5 cases/100 PYs) and 116 (10 cases/100 PYs), respectively. In reference to the ART alone, the IPT plus ART reduced the likelihood of death significantly (aHR 0.48; 95% CI 0.38-0.69) and median time to death was about 26 months (IQR 19-34). Moreover, WHO stage IV (aHR 2.42: 95% CI 1.42-4.11), CD4 values ≥350 cells/mm3 (aHR 0.52; 95% CI 0.28-0.94), adherence to ART (aHR 0.12; 95% CI 0.08-0.20), primary levels of education (aHR 2.20; 95% CI 1.07-4.52); and alcohol consumption (aHR 1.71; 95% CI 1.04-2.81) were factors strongly associated with mortality.

Conclusion: We found that PLHIV treated by the IPT plus ART had a lower likelihood of mortality and delayed time-to-death when compared to patients treated by ART alone.

Fig 1. Flow diagram showing selection of study patients on IPT plus ART and ART alone.

Fig 2. Kaplan Meier survival curve among HIV patients treated by ART alone versus INH plus ART.