Predictors of mortality and loss to follow-up among drug resistant tuberculosis patients in Oromia Hospitals, Ethiopia: A retrospective follow-up study

Abstract

Background: Drug resistance tuberculosis (DR-TB) patients' mortality and loss to follow-up (LTF) from treatment and care is a growing worry in Ethiopia. However, little is known about predictors of mortality and LTF among drug-resistant tuberculosis patients in Oromia region, Ethiopia. The current study aimed to identify predictors of mortality and loss to follow-up among drug resistance tuberculosis patients in Oromia Hospitals, Ethiopia.

Methods: A retrospective follow up study was carried out from 01 November 2012 to 31 December 2017 among DR-TB patients after calculating sample size using single proportion population formula. Mean, median, Frequency tables and bar charts were used to describe patients' characteristics in the cohort. The Kaplan-Meier curve was used to estimate the probability of death and LTF after the treatment was initiated. The log-rank test was used to compare time to death and time to LTF. The Cox proportional hazard model was used to determine predictors of mortality and LTF after DR-TB diagnosis. The Crude and adjusted Cox proportional hazard ratio was used to measure the strength of association whereas p-value less than 0.05 were used to declare statistically significant predictors.

Result: A total of 406 DR-TB patients were followed for 7084 person-months observations. Among the patients, 71 (17.5%) died and 32 (7.9%) were lost to follow up (LTF). The incidence density of death and LTF in the cohort was 9.8 and 4.5 per 1000 person-months, respectively. The median age of the study participants was 28 years (IQR: 27.1, 29.1). The overall cumulative survival probability of patients at the end of 24 months was 77.5% and 84.5% for the mortality and LTF, respectively. The independent predictors of death was chest radiographic findings (AHR = 0.37, 95% CI: 0.17-0.79) and HIV serostatus 2.98 (95% CI: 1.72-5.19). Drug adverse effect (AHR = 6.1; 95% CI: 2.5, 14.34) and culture test result (AHR = 0.1; 95% CI: 0.1, 0.3) were independent predictors of LTF.

Conclusion: This study concluded that drug-resistant tuberculosis mortality and LTF remains high in the study area. Continual support of the integration of TB/HIV service with emphasis and work to identified predictors may help in reducing drug-resistant tuberculosis mortality and LTF.

Fig 1. Treatment outcomes of drug resistance tuberculosis infected patents in Oromia region, Ethiopia, 2020.

Fig 2. Kaplan–Meier survival estimate for mortality of drug resistance tuberculosis infected patents in Oromia region, Ethiopia, 2020.

Fig 3. Kaplan–Meier survival estimate for loss to follow up of drug resistance tuberculosis infected patents in Oromia region, Ethiopia, 2020.

Fig 4. Kaplan–Meier survival estimate for LTF of drug resistance tuberculosis infected patents for HIV reactive and non-reactive patients in Oromia region, Ethiopia, 2020.

Fig 5. Kaplan–Meier survival estimate for mortality of drug resistance tuberculosis infected patents for patients with co morbidity and without co morbidity in Oromia region, Ethiopia, 2020.