The Auditory Outcomes in non-blast related Traumatic Brain Injury and the Role of Severity, Aetiology and Gender: A scoping review

Kübra Bölükbaş^1,2*Laura Edwards^3,4Olivia Phillips⁵Kathryn Fackrell^1,2

• ¹Hearing Sciences, Mental Health and Clinical Neurosciences, School of Medicine, University of Nottingham, Nottingham, England, United Kingdom
• ²Nottingham Hearing Biomedical Research Centre, University of Nottingham, Nottingham, United Kingdom
• ³Division of Rehabilitation Medicine, University Hospitals of Derby and Burton NHS Foundation Trust, Derby, United Kingdom
• ⁴Centre for Rehabilitation and Ageing Research, School of Medicine, University of Nottingham, UK, Nottingham, United Kingdom
• ⁵Lifespan and Population Health, School of Medicine, University of Nottingham, Nottingham, United Kingdom

Introduction: Traumatic brain injury (TBI) i can cause a wide range of auditory outcomes. This review aimed to investigate common auditory outcomes associated with TBI and explore variations based on severity, aetiology, and gender.A scoping review was conducted using an established methodological framework, which involved electronic and manual searches of databases and journals. Records published in English were included, which focused on auditory outcomes and assessments associated with non-blast related TBI in individuals 18 years and older. From 19031 records, 61 met the inclusion criteria. Data were collated and categorised based on the study objectives.Results: Pure-tone audiometry (56/61) was the most commonly used hearing assessment, followed by otoscopy (27/61), whilst for tinnitus and hyperacusis assessments varied from questionnaires to self-reported problems. Different types of hearing loss were reported; conductive to mixed, of these 41% noted sensorineural hearing loss (SNHL). Normal hearing (≤ 20/25 dB HL) was reported in 31% (19/61) of the studies, however, five studies found abnormal results in central auditory tests despite normal hearing. Severe TBI was reported more frequently compared to other severities (10/23). Although SNHL was noted in 4 studies related to severe TBI, various outcomes were observed ranging from normal hearing to total deafness. Motor-vehicle accidents (MVA) were the most common aetiology (36/61), followed by falls, assaults, and sports injuries. Following MVA, SNHL was observed in 12 studies and CHL was observed across 10 studies. Out of 61 articles, 53% included only male patients, and SNHL was observed more frequently in males (17/33), whilst normal hearing and other types of hearing loss were noted in both genders.Conclusion: TBI-related auditory impairments are complex, with inconsistent assessment methods and reporting gaps complicating data synthesis. Standardised clinical practices and screening guidelines are crucial for improving auditory assessment and management in this population.