posted on 2021-09-28, 18:02authored byKelly M. Reavis, Jonathan M. Snowden, James A. Henry, Frederick J. Gallun, M. Samantha Lewis, Kathleen F. Carlson
Purpose: Evidence suggests that military blast exposure may lead to self-reported hearing difficulties despite audiometrically normal hearing. Research identifying potential mechanisms of this association remains limited. The purpose of this article is to evaluate the associations between blast, posttraumatic stress disorder (PTSD), and self-reported hearing difficulty, and to examine PTSD as a possible mediator of the association between blast exposure and hearing difficulty.
Method: We used baseline data from the Noise Outcomes in Service members Epidemiology (NOISE) study (n = 477). Participants in this study undergo a comprehensive hearing, and tinnitus if applicable, evaluation and complete a large number of surveys. Pertinent data extracted from these surveys included information on participant’s demographics, military service history, including exposure to blast, and health conditions such as symptoms of PTSD. Using regression models and following a formal causal mediation framework, we estimated total associations, natural direct and indirect associations, and percent mediated.
Results: We found that individuals with blast exposure had higher prevalence of both probable PTSD and self-reported hearing difficulty than individuals who were not blast exposed. Compared with participants without blast exposure, those with blast exposure had twice the prevalence of self-reported hearing difficulty, with 41% of the association mediated through probable PTSD.
Conclusion: As PTSD is a possible mediator of the association between blast exposure and hearing difficulty, Service members and Veterans with normal pure-tone hearing sensitivity who report hearing difficulties and a history of blast exposure may benefit from evaluation for PTSD symptoms.
Supplemental Material S1. Directed acyclic graph depicting causal pathways between blast exposure and self-reported hearing difficulty with mediation by PTSD.
Reavis, K. M., Snowden, J. M., Henry, J. A., Gallun, F. J., Lewis, M. S., & Carlson, K. F. (2021). Blast exposure and self-reported hearing difficulty in Service members and Veterans who have normal pure-tone hearing sensitivity: The mediating role of posttraumatic stress disorder. Journal of Speech, Language, and Hearing Research. Advance online publication. https://doi.org/10.1044/2021_JSLHR-20-00687
Funding
This work was supported by a Department of Defense Congressionally Directed Medical Research Program Investigator- Initiated Research Award (PR121146), a Joint Warfighter Medical Research Program Award (JW160036), and a U.S. Department of Veterans Affairs (VA) Rehabilitation Research and Development (RR&D) Research Career Scientist Award (1 IK6 RX002990-01). This material is the result of work supported with resources and the use of facilities at the VA RR&D National Center for Rehabilitative Auditory Research (VA RR&D NCRAR Center Award; C9230C) at the VA Portland Health Care System in Portland, Oregon, as well as the Department of Defense, Hearing Center of Excellence in San Antonio, Texas.