Statistical factors associated with utilisation of ototoxicity monitoring services for multi-drug-resistant tuberculosis patients in the Western Cape

BACKGROUND: South Africa is a high-burden multi-drug-resistant tuberculosis (MDR-TB) country. Previously, standard MDR-TB treatment regimen in South Africa included kanamycin, an aminoglycoside, which can cause permanent hearing loss in patients. South African National Tuberculosis Control programme’s guidelines for the management of patients with MDR-TB were revised in 2011 to support outpatient-based models. This, in turn, required reorganisation of ototoxicity monitoring services to support these new models of service delivery. OBJECTIVES: The aim of this study was to determine factors associated with the utilisation of ototoxicity monitoring services for patients with MDR-TB who accessed treatment as outpatients. METHOD: A retrospective review of medical records of patients who attended ototoxicity monitoring clinic at a central TB hospital in Cape Town during 2012–2013 was conducted. A total of 801 medical folders were reviewed: 415 (51.8%) males and 386 (48.2%) females, median age 37 (range 7–85) years. RESULTS: Ten per cent of patients attended all the recommended six-monthly appointments. Patients who presented with hearing loss at baseline or developed hearing loss after treatment initiation were more likely to attend their appointments. Patients were also more likely to attend their appointments if a baseline audiometric assessment was conducted within 1 month of MDR-TB treatment initiation. CONCLUSION: This study revealed that outpatient-based ototoxicity monitoring services were largely underutilised by patients. Development of hearing loss and prompt determination of a baseline audiogram were associated with a higher likelihood of attendance of ototoxicity monitoring appointments. Therefore, utilisation of outpatient-based ototoxicity monitoring services is likely to be improved by identifying patients early and monitoring them closely.