Associations of Traumatic Brain Injury and Hearing: Results From the Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS)

Objective: To examine associations of traumatic brain injury (TBI) with self-reported and clinical measures of hearing function. Setting: Four US communities. Participants: A total of 3176 Atherosclerosis Risk in Communities Study participants who attended the sixth study visit in 2016-2017, when hearing was assessed. Design: Prospective cohort study. TBI occurring prior to the hearing assessment was defined using self-reported questions and “International Classification of Diseases-9th/10th Edition” (ICD-9/10) codes. Main Measures: Hearing function was assessed by self-reported questionnaires and clinically measured indices (audiometry [4-frequency pure tone average for each ear] and speech-in-noise testing). Linear, logistic, and multinomial logistic models adjusted for sociodemographics, vascular risk factors, and occupational noise exposure were used to examine associations. Results: Participants were a mean age of 79 years, 59% were female, 21% were of self-reported Black race, and 33% had a history of TBI (median time from first TBI to hearing assessment: 39 years (25th-75th percentile = 19-63 years). Compared to participants without TBI, participants with prior TBI had higher age-adjusted prevalence of self-reported hearing loss (42.3% vs 35.3%), tinnitus (28.0% vs 23.8%), hearing aid use (23.4% vs 17.8%), pure tone average > 40 dB (30.6% vs 24.8%), and presence in the lowest quartile of speech-in-noise performance (27.6% vs 22.8%). With further adjustment, and particularly with adjustment for occupational noise exposure, associations with hearing measures were largely no longer statistically significant. In secondary analyses of associations of TBI frequency and severity with hearing function, results were similar to our main analyses, without evidence of dose-dependent associations. Conclusions and Relevance: In this community-based cohort, prior TBI was associated with impaired hearing on both self-reported and clinically measured assessments, but these associations were attenuated after adjustment for occupational noise exposure. These results underscore the importance of the consideration of loud noise exposures, which may confound associations of TBI with hearing, in future studies.