Effects of Noise Exposure, Race, and Years of Service on Hearing in U.S. Army Soldiers

TLDR

The U.S. Army has implemented a comprehensive hearing conservation program over the past two decades to reduce hearing loss among soldiers and civilian employees. This study compared hearing loss across race, noise exposure, and service duration among soldiers. The authors used age‑corrected hearing threshold levels from a central Army registry to conduct the analysis.

Abstract

Over the last two decades the U.S. Army has instituted a comprehensive hearing conservation program (HCP) to reduce the prevalence of hearing loss in soldiers and civilian employees. As a component of this program, hearing threshold levels (HTLs) are stored in a central computerized Army-wide hearing conservation data registry. The aim of this study was to analyze the hearing threshold data to compare the hearing loss among soldiers representing different (1) race groups, (2) noise exposure groups, and (3) durations of military service. HTLs were age-corrected using data base B values from IS0 1999 (1990). As may be expected, soldiers exposed to high noise levels had significantly poorer hearing than the group of soldiers with limited noise exposure. On the average, results indicated a significant difference in HTLs among the race groups with black soldiers having the most sensitive hearing and white soldiers having the poorest. Also, subjects with greater durations of military service had the least sensitive hearing. Finally, race and years of service factors were found to interact in their effect on HTL. The findings are discussed in terms of implications of race differences, normative data, and effectiveness of the U.S. Army HCP.