By David Jung, M.D., Ph.D., and Elliot Kozin, M.D.
Traumatic brain injury (TBI) is a major cause of morbidity and mortality in the United States and worldwide. There are an estimated 3.2 to 5.3 million individuals in the United States who are living with a TBI-related disability, and the estimated societal cost is in excess of $76 billion per year. Auditory conditions, including hearing loss, tinnitus, and hyperacusis, have been recognized as a common consequence of TBI, even in the absence of a temporal bone fracture.
As published in the journal Otolaryngology–Head & Neck Surgery in June 2020, we evaluated adult patients with typical hearing thresholds and a history of TBI for subjective hearing loss, tinnitus (ringing in the ears without a sound source), a feeling of ear fullness, hyperacusis (sensitivity to sounds), and autophony (unusually loud hearing of one’s own voice). We also administered questionnaires specific to certain hearing conditions: the Hearing Handicap Inventory for Adults, the Tinnitus Handicap Inventory, and the Hyperacusis Questionnaire.
Our study was among the first to investigate audiometric patterns, auditory conditions, and associated handicap in individuals following TBI with pure tone averages in the typical range. Participants with TBI not only commonly reported a range of auditory conditions, but also almost half the participants sustained head injury six years before participation in this study, suggesting the chronic burden of these symptoms.
We concluded that despite typical hearing thresholds, individuals with TBI experience a decrease in auditory quality-of-life metrics.
A 2018 ERG scientist, David Jung, M.D., Ph.D., is an assistant professor of otolaryngology–head and neck surgery, Harvard Medical School/Massachusetts Eye and Ear. A 2018 ERG scientist generously funded by the General Grand Chapter Royal Arch Masons International, Elliot Kozin, M.D., is an otolaryngologist at Massachusetts Eye and Ear.
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