Sustained high fatality during TB therapy amid rapid decline in TB mortality at population level: A retrospective cohort and ecological analysis from Shiselweni, Eswatini

Abstract

AbstractObjectivesDespite declining TB notifications in Southern Africa, TB‐related deaths remain high. We describe patient‐ and population‐level trends in TB‐related deaths in Eswatini over a period of 11 years.MethodsPatient‐level (retrospective cohort, from 2009 to 2019) and population‐level (ecological analysis, 2009–2017) predictors and rates of TB‐related deaths were analysed in HIV‐negative and HIV‐coinfected first‐line TB treatment cases and the population of the Shiselweni region. Patient‐level TB treatment data, and population and HIV prevalence estimates were combined to obtain stratified annual mortality rates. Multivariable Poisson regressions models were fitted to identify patient‐level and population‐level predictors of deaths.ResultsOf 11,883 TB treatment cases, 1302 (11.0%) patients died during treatment: 210/2798 (7.5%) HIV‐negative patients, 984/8443 (11.7%) people living with HIV (PLHIV), and 108/642 (16.8%) patients with unknown HIV‐status. The treatment case fatality ratio remained above 10% in most years. At patient‐level, fatality risk was higher in PLHIV (aRR 1.74, 1.51–2.02), and for older age and extra‐pulmonary TB irrespective of HIV‐status. For PLHIV, fatality risk was higher for TB retreatment cases (aRR 1.38, 1.18–1.61) and patients without antiretroviral therapy (aRR 1.70, 1.47–1.97). It decreases with increasing higher CD4 strata and the programmatic availability of TB‐LAM testing (aRR 0.65, 0.35–0.90). At population‐level, mortality rates decreased 6.4‐fold (−147/100,000 population) between 2009 (174/100,000) and 2017 (27/100,000), coinciding with a decline in TB treatment cases (2785 in 2009 to 497 in 2017). Although the absolute decline in mortality rates was most pronounced in PLHIV (−826/100,000 vs. HIV‐negative: −23/100,000), the relative population‐level mortality risk remained higher in PLHIV (aRR 4.68, 3.25–6.72) compared to the HIV‐negative population.ConclusionsTB‐related mortality rapidly decreased at population‐level and most pronounced in PLHIV. However, case fatality among TB treatment cases remained high. Further strategies to reduce active TB disease and introduce improved TB therapies are warranted.