Prevalence and predictors of adverse events among patients receiving Multi-Drug Resistant Tuberculosis treatment at Kibong’oto Infectious Disease Hospital, Tanzania: a retrospective study

Abstract Background: Multidrug-resistant tuberculosis (MDR-TB) has been an emerging global public health threat and area of serious concern towards efforts of global TB control. The major challenge in MDR-TB management in Tanzania is the lack of up-to-date data on adverse events (AEs) associated with MDR-TB regimens. This study aimed to determine the prevalence and factors associated with AEs among patients treated for MDR-TB at Kibong’oto Infectious Diseases Hospital (KIiDH) Kilimanjaro, Tanzania. Methods: This was a hospital-based retrospective cross-sectional study whereby patient information was collected from patient files using a structured data extraction tool. Data from patients treated for MDR-TB at KIDH in Kilimanjaro, Tanzania from 2009 to 2019 were used for analysis. Patients with incomplete data were excluded from analysis. Adverse events were recorded either as documented by the physician or by comparing baseline laboratory results against ensuing results after initiating treatment. AE severity was graded according to the Common Terminology Criteria for Adverse Events. Results: A total of 260 patients were analyzed. Adverse events were recorded among 87.7% of the study population with a wide spectrum of these adverse events. Most common AEs included hepatotoxicity (40.4%), nephrotoxicity (37.7%), anaemia (24.2%) and death (10%). Patients previously treated for drug susceptible tuberculosis (DS-TB) had 2.75(95%CI: 1.20–6.29; p=0.017) times higher odds of developing AEs compared to those never treated for DS-TB. Predictors of death were: HIV co-infection (adjusted odds ratio (AOR) 3.3, 95%CI: 1.40-7.74, p=0.006); and patients with a low body mass index (BMI) <18.5kg/M2. A shorter MDR-TB regimen (AOR 2.4, 95%CI: 1.03-5.73; p=0.04) was a predictor of death as an AE. Conclusion: MDR-TB patients on treatment present with a high proportion of AEs. Patients with HIV co-infection, history of previous DS-TB treatment, those with a BMI <18.5kg/M2 and patients placed on shorter regimes are at an increased risk of developing AEs. Low BMI, HIV co-infection and use of the shorter MDR-TB regimen are associated with increased odds of dying among patients treated for MDR-TB. Therefore, it is pertinent to strengthen continuous follow-up among patients presenting with significant predictors of AEs.