The 5-year incidence and progression of hearing loss: the epidemiology of hearing loss study.

Abstract

Hearing impairment affects many older adults, but the incidence is unknown. To determine the 5-year incidence and progression of hearing impairment. A longitudinal, population-based study of adults aged 48 to 92 years at baseline examination. Hearing sensitivity was measured twice, 5 years apart. Testing was conducted at the Beaver Dam Community Hospital, Beaver Dam, Wis. A total of 1636 participants without hearing loss and 1085 participants with hearing loss at the baseline examination in 1993-1995 were reexamined in 1998-2000. The examinations included otoscopy, screening tympanometry, and tone air- and bone-conduction audiometry. Incidence of hearing impairment was defined as a pure-tone average (PTA) of thresholds at 500, 1000, 2000, and 4000 Hz (PTA 0.5, 1, 2, and 4 kHz) greater than 25 dB HL (hearing level) in either ear at follow-up among those without hearing loss at baseline. Progression was defined as a change of more than 5 dB in the PTA 0.5, 1, 2, and 4 kHz among those with hearing loss at baseline. The 5-year incidence of hearing impairment was 21%. More than half of those with hearing loss at baseline experienced a decline in hearing. Age was an important risk factor for both incidence and progression. Male sex, occupation, and education were associated with the incidence of hearing loss after adjusting for age. Older adults have a high risk of developing hearing loss. Among those with hearing loss, most experience further declines in hearing sensitivity over time. These data indicate that hearing impairment is an important public health problem and underscore the need for appropriate hearing screening and treatment.