Multidrug resistant tuberculosis (MDR-TB) in Eritrea: a retrospective cohort analysis of mortality and associated factors (2013 – 2023)

Background Multi-drug resistant tuberculosis (MDR-TB) continues to be a pressing global health concern, indiscriminate of country border and defined by higher mortality and higher treatment costs. Here, we sought to describe the MDR/RR-TB patients’ clinical profile and outcomes in Eritrea. In particular, focus was directed at hemato-biochemical predictors of mortality. Methods This study was a retrospective (2013–2023) analysis of patients records at the Merhano MDR/RR-TB hospital in Asmara, Eritrea. In total, records from 257 patients were reviewed. Data on treatment outcomes, hematological, biochemical and demographic characteristics was subsequently abstracted using a structured check-list. We incorporated Kaplan-Meier curve and multivariate Cox regression model to evaluate the relationship between covariates and mortality. Results The mean age (± Standard deviation (SD)) at enrolment was: 41.7 years (± 16.5), and the number of males in the cohort was 157(61.1%). Of all patients, 91(37.80%) had anemia (severe anemia, 18(7.5%); 205(79.8%) experienced adverse drug reaction (ADR); 30 (12.1%) had HIV; 45 (20.4%) had eGFR Creat < 60 mL/min; 27(11.6%) had elevated BUN; 33(14.5%) had APRI score > 0.5; 45(21.6%) had hypothyroidism; 14 (5.9%) had thrombocytopenia; and 126(53.4%) had thrombocytosis. During treatment, 162 (63.0%, 95% CI: 57 – 69.6%) patients were cured, 45(17.5%, 95% CI: 13.5 – 22.0%) completed treatment, 40 (15.6%, 95% CI: 10.5-19.4%) died, and 8(3.1%, 95% CI: 1.2 – 5.1%) were Lost to follow up. Median (IQR) time to death was 33 days (10–130 days). After 137–321 person days follow up (PDFU), the incidence of death (95% CI) was 2.91(2.11 – 4.11) per 10–000 PDFU. Predictors of mortality included age >60 years; Weight <30 Kg at baseline; Thrombocytopenia; Severe anemia; APRI score > 0.5; Hypothyroidism; elevated BUN, high serum creatinine (SCr) levels; and eGFR Creat < 60 mL/min. In the multivariate Cox regression model, a unit increase in hemoglobin concentration and weight reduced the risk of death by 0.79(95% CI: 0.67 – 0.93), P = 0.005 and 0.96(95% CI: 0.91-1.01), respectively. Further, higher likelihood of death was associated with elevated SCr (>12 mg/dL) levels (aHR = 6.33 (95% CI: 2.33 – 17.19), P<0.001, and APRI Score >0.5 (aHR = 2.78(95% CI: 1.65 – 4.70), P<0.001. In contrast, a unit increase in age increased the risk of death (aHR = 1.045(95 CI%: 1.02 – 1.07), P<0.001. Conclusion The magnitude of death and other unfavorable treatment outcome for MDR/RR-TB was low. Of greater concern, however, was the critical condition of patients at presentation. Proactive strategies are needed to improve early detection of MDR/RR-TB and supportive care in patients with severe complications. In addition, additional research on MDR/TB-mortality is needed, especially among vulnerable subpopulations.