In Pursuit of Preventive Audiology in South Africa: Scoping the Context for Ototoxicity Assessment and Management

Prevailing Practices in Ototoxicity Monitoring in Individuals With Head and Neck Cancer Undergoing Radiotherapy and Chemoradiotherapy: A Scoping Review

PURPOSE

The aim of the current scoping review is to identify the studies reporting ototoxicity monitoring in individuals with head and neck cancer (HNC) undergoing radiation therapy and/or chemoradiation therapy across the world. The specific objectives were to identify and report the test protocol used, identify the most common timeline of follow-up, and identify barriers and facilitators influencing the implementation of the monitoring program.

METHOD

A comprehensive search was conducted across six electronic databases, including PubMed, Embase, Web of Science, Scopus, Google Scholar, and ProQuest. The scoping review method adhered to relevant guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) and frameworks. The database search was carried out by two independent researchers, and studies were selected based on specific inclusion and exclusion criteria.

RESULTS

This scoping review identified 13 studies that fulfilled the inclusion criteria of this study. Only one study reported findings from the perspective of ototoxicity monitoring. Another study explicitly mentioned that ototoxicity monitoring was a standard of care in their hospital. Only one study reported using the relevant guidelines for monitoring ototoxicity. Specialized tests such as high-frequency audiometry, distortion product otoacoustic emissions, and vestibular tests were rarely used. Ototoxicity monitoring was influenced by awareness-related factors, technical factors, treatment-related factors, and organizational factors.

CONCLUSIONS

Research on ototoxicity monitoring programs is in its early stages, highlighting the need for standardized practices and multidisciplinary collaboration to enhance health care services for HNC patients. A standardized approach, improved awareness, and the incorporation of patient perspectives are crucial to enhancing ototoxicity monitoring in HNC patients.

Hearing Function in Adults with Rheumatoid Arthritis: A Scoping Review for Preventive Audiology Planning

Rheumatoid arthritis (RA) is a disease which affects the joints and bones of individuals diagnosed with this condition. Little remains known about the possible impact of this disease on hearing function, particularly the possibilities of preventive audiology in low-and-middle-income countries (LMICs). The study aimed to review published evidence on hearing function in adults with RA. A scoping review of literature from January 2010 to August 2020 was conducted using Sage, ScienceDirect, PubMed, Scopus, Medline, ProQuest and Google Scholar. Studies published in English which reported on the audiological function in adult individuals with RA were included in the review. From 832 initial title records, 18 articles were included into the final scoping review. A qualitative analysis of the reviewed evidence revealed four themes: (1) hearing loss occurs-causality still unclear; (2) nature, degree and configuration of the hearing loss varies; (3) systematic and standardized assessment battery required; and (4) sensitive and specific measures for early detection needed. The occurrence of hearing loss in this population ranges between 21.3 and 66.6%, and this increased where advanced sensitive measures such as ultrahigh frequency and otoacoustic emission (OAEs) measures were included in the test battery. Many audiological tests were used in the studies in order to identify the presence and type of hearing loss in these individuals, with basic audiometry testing being the most commonly used. The most prevalent type of hearing loss was found to be a high frequency sensorineural hearing loss (SNHL), with mixed (MHL) and conductive hearing losses (CHL) being present in some of the individuals. Causal links between RA and hearing loss remains unclear. Although there are limited studies which have reported on the audiological function in the population with RA, the studies which have been reviewed seem to establish an association between RA and the presence of hearing loss. The published high prevalence of hearing loss in this population, when compared to healthy control groups raises implications for well-designed studies that utilize sensitive audiologic diagnostic measures, with clear inclusion and exclusion criteria to ensure more accurate causal links establishment between RA and hearing loss in this population.

A longitudinal community-based ototoxicity monitoring programme and treatment effects for drug-resistant tuberculosis treatment, Western Cape

Background

South Africa has a high burden of drug-resistant tuberculosis (DRTB) and until recently, ototoxic aminoglycosides were predominant in treatment regimens. Community-based ototoxicity monitoring programmes (OMPs) have been implemented for early detection of hearing loss and increased patient access.

Objectives

A longitudinal study was conducted to describe the service delivery characteristics of a community-based OMP for DRTB patients facilitated by CHWs as well as observed ototoxic hearing loss in this population.

Method

A descriptive retrospective record review of longitudinal ototoxicity monitoring of 194 DRTB patients undergoing treatment at community-based clinics in the city of Cape Town between 2013 and 2017.

Results

Follow-up rates between consecutive monitoring assessments reached as high as 80.6% for patients assessed by CHWs. Few patients (14.2% – 32.6%) were assessed with the regularity (≥ 6 assessments) and frequency required for effective ototoxicity monitoring, with assessments conducted, on average, every 53.4–64.3 days. Following DRTB treatment, 51.5% of patients presented with a significant ototoxic shift meeting one or more of the American Speech-Language-Hearing Association (ASHA) criteria. Deterioration in hearing thresholds was bilateral and most pronounced at high frequencies (4 kHz – 8 kHz). The presence of pre-existing hearing loss, human immunodeficiency virus co-infection and a history of noise exposure were significant predictors of ototoxicity in patients.

Conclusion

DRTB treatment with kanamycin resulted in significant deterioration of hearing longitudinally, predominantly at high frequencies. With ongoing training and supportive supervision, CHWs can facilitate community-based ototoxicity monitoring of DRTB patients. Current protocols and guidelines may require reassessment for appropriate community-based ototoxicity monitoring.

Community-Based Ototoxicity Monitoring for Drug-Resistant Tuberculosis in South Africa: An Evaluation Study

In response to the drug-resistant tuberculosis (DRTB) ototoxicity burden in South Africa, ototoxicity monitoring has been decentralised, with community health workers (CHWs) acting as facilitators. This study describes a community-based ototoxicity monitoring programme (OMP) for patients with DRTB. Findings are compared to the recommended guidelines for ototoxicity monitoring, the OMP protocol and published studies. This was a retrospective study of longitudinal ototoxicity monitoring of 831 patients with DRTB, using data collected at community-based clinics in the City of Cape Town between 2013 and 2017. Approximately half (46.8%) of the patients had an initial assessment conducted in accordance with the OMP protocol recommendations, and follow-up rates (79.5%) were higher than those of a similar DRTB programme. However, patients in this study were not monitored within the timeframes or with the regularity recommended by the guidelines or the OMP protocol. Extended high-frequency pure-tone audiometry (27.5%) was underutilised by testers and data recording was inconsistent (e.g., 37.7% of patient gender was not recorded by testers). Community-based OMP using CHWs to facilitate monitoring showed improvement over previous hospital-based reports, with more accessible services and higher follow-up rates. However, to improve OMP outcomes, OMP managers should reassess current protocols and data recording practices.