Incidence and predictors of mortality among persons with rifampicin-resistant tuberculosis and HIV in Mozambique

Abstract

Rifampicin-Resistant Tuberculosis (RRTB) is associated with a high risk of mortality during treatment. This study aims to describe the baseline characteristics associated with incidence of mortality in persons with rifampicin-resistant tuberculosis (P-RRTB) in a rural setting in Mozambique. We analyzed cohort data collected retrospectively from paper medical files and electronic medical records of P-RRTB who were routinely treated at Carmelo Hospital of Chokwe (Gaza province, Mozambique), from 1st January 2015 to 31st December 2020. Kaplan-Meier survival curves and adjusted Cox regression analyses were used to model the time to death and associated factors of mortality. Overall, 151 P-RRTB contributed to a total number of 1812 person-months (PM) of treatment follow-up. The overall mortality rate was 1.9 per 100 person-months (95% confidence interval [CI]: 1.3-2.1). Adjusted Cox regression predicted higher risk of mortality in those treated with injectable anti-RRTB second line drugs (SLD), (adjusted hazard ratio [aHR] 3.72, 95% CI 1.23-11.22, p = 0.020), had a parenchymal lesion with more than 50% fibrosis (aHR 3.06, 95% CI 1.38-6.79, p = 0.006), presented right ventricular dysfunction on the echocardiogram with venous assessment (aHR 3.18, 95% CI 1.15-8.83, p = 0.026), and manifested baseline hemoglobin (Hgb) = 8.0-9.9 g/dL (aHR 2.82, 95% CI 1.09-7.27, p = 0.032), as well Hgb < 7.9 g/dL (aHR 3.06, 95%CI 1.24-7 0.51, p = 0.015). However, lower risk of mortality was predicted in those who had an optimal immunovirological response to ART (aHR 0.18, 95% CI 0.04-0.93, p = 0.040). Kaplan-Meier analysis showed higher cumulative incidence of mortality after 3 months of follow-up, above 26% in those with immunovirological failure to ART therapy (p = 0.006), 45% with Hgb < 7.9 g/dL (p < 0.001), 23% in treated with injectables-based drugs (p = 0.03), 39% with parenchymal lesion > 50% fibrosis on the chest X-ray (p < 0.001), 56% with right ventricular dysfunction (p = 0.003). Mortality risk among P-RRTB was higher in those with anemia, injectable anti-RRTB medications, lung lesions > 50% fibrosis, and right ventricular dysfunction.