The complex relationship between human immunodeficiency virus infection and death in adults being treated for tuberculosis in Cape Town, South Africa Infectious Disease epidemiology

Abstract

Background: Despite recognised treatment strategies, mortality associated with tuberculosis (TB) remains significant. Risk factors for death during TB treatment have been described but the complex relationship between TB and HIV has not been fully understood. Methods: A retrospective analysis of all deaths occurring during TB treatment in Cape Town, South Africa between 2009 and 2012 were done to investigate risk factors associated with this outcome. The main risk factor was HIV status at the start of treatment and its interaction with age, sex and other risk factors were evaluated using a binomial regression model and thus relative risks (RR) are reported. Results: Overall in the 93,133 cases included in the study 4619 deaths (5 %) were recorded. Across all age groups HIV-positive patients were more than twice as likely to die as HIV-negative patients, RR = 2.19 (95 % CI: 2.03-2.37). However in an age specific analysis HIV-positive patients 15-24 and 25-34 years old were at an even higher risk of dying than HIV-negative patients, RR = 4.82 and RR = 3.76 respectively. Gender also modified the effect of HIV- with positive women having a higher risk of death than positive men, RR = 2.74 and RR = 1.94 respectively. Conclusion: HIV carries an increased risk of death in this study but specific high-risk groups pertaining to the impact of HIV are identified. Innovative strategies to manage these high risk groups may contribute to reduction in HIV-associated death in TB patients.