Time to tuberculosis development and its predictors among HIV-positive patients: A retrospective cohort study

Abstract

Objectives: To assess the incidence and predictors of time to Tuberculosis (TB) development among Human Immunodeficiency Virus (HIV) positive patients attending follow-up care in health facilities of Hawassa, Ethiopia.

Methods: We conducted a retrospective cohort study from April 1-30, 2023. A total of 422 participants were selected using a simple random sampling method. Data was collected from the medical records of patients enrolled between January 1, 2018 -December 31, 2022, using the Kobo toolbox. We used Statistical Package for Social Studies (SPSS) version 26.0 for data analysis. To estimate the duration of TB-free survival, we applied the Kaplan-Meier survival function and fitted Cox proportional hazard models to identify the predictors of time to TB development. Adjusted hazard ratios (AHR) with 95% confidence intervals were calculated and statistical significance was declared at a P-value of 0.05.

Results: The overall incidence rate of TB among HIV-positive patients was 6.26 (95% CI: 4.79-8.17) per 100 person-years (PYs). Patients who did not complete TB Preventive Therapy (TPT) were more likely to have TB than those who did (AHR = 6.2, 95% CI: 2.34-16.34). In comparison to those who began antiretroviral therapy (ART) within a week, those who began after a week of linkage had a lower risk of TB development (AHR = 0.44, 95% CI: 0.21-0.89). Patients who received ART for six to twelve months (AHR = 0.18, 95% CI: 0.05-0.61) and for twelve months or longer (AHR = 0.004, 95% CI: 0.001-0.02) exhibited a decreased risk of TB development in comparison to those who had ART for less than six months.

Conclusion: The incidence of TB among HIV-positive patients is still high. To alleviate this burden, special attention should be given to regimen optimization and provision of adherence support for better completion of TPT, sufficient patient preparation, thorough clinical evaluation for major (Opportunistic Infections) OIs prior to starting ART, and ensuring retention on ART.

Fig 1. Kaplan—Meier survival estimate of study participants, Hawassa, Ethiopia, January 1, 2018—December 31, 2022.

Fig 2. Kaplan—Meier survival estimate of study participants, by ART initiation time, Hawassa, Ethiopia, January 1, 2018—December 31, 2022.

Fig 3. Kaplan—Meier survival estimate of study participants, by TPT completion, Hawassa, Ethiopia, January 1, 2018—December 31, 2022.