Blast-related ear injuries among U.S. military personnel

Abstract

Blast-related ear injuries are a concern during deployment because they can compromise a servicemember's situational awareness and adversely affect operational readiness. The objectives of this study were to describe blast-related ear injuries during Operation Iraqi Freedom, identify the effect of hearing protection worn at the point of injury, and explore hearing loss and tinnitus outcomes within one year after injury. The Expeditionary Medical Encounter Database was used to identify military personnel who survived blast-related injury, and it was linked with outpatient medical databases to obtain diagnoses of hearing loss and tinnitus. The prevalence of ear injuries was 30.7% (1,223 of 3,981). The most common ear injury diagnoses were "inner or middle ear injury involving tinnitus" and tympanic membrane (TM) rupture. Hearing protection reduced the odds of ear injury involving tinnitus. Personnel with TM rupture had higher odds of hearing loss (odds ratio [OR] = 6.65, 95% confidence interval [CI] = 5.04-8.78) and tinnitus outcomes (OR = 4.34, 95% CI = 3.12-6.04) than those without TM rupture. Ear injuries and hearing impairment are frequent consequences of blast exposure during combat deployment. Hearing protection is warranted for all servicemembers at risk of blast exposure.