Perspectives on Noise-Induced Hearing Loss

Abstract

Hearing impairment is the third most prevalent chronic disability in the United States, and hearing loss in the speech frequency region (pure-tone average threshold at 0.5, 1, 2, and 4 kHz ≥ 25 dB) is currently estimated to affect 29 million Americans ages 20–69 years based on 2003–2004 data (16% of population; Agrawal et al. 2008). When the higher frequencies are considered (pure-tone average at 3, 4, and 6 kHz ≥ 25 HL), the number affected doubles (Agrawal et al. 2008). Consistent with this, the National Institutes of Health has estimated that some 15% of Americans between the ages of 20 and 69 have hearing loss at higher test frequencies, suggesting the hearing loss may have been caused by exposure to loud sound (National Institute on Deafness and Other Communication Disorders 2002).