Impact of hearing difficulty on dependence in activities of daily living (ADL) and mortality: a 3-year cohort study of community-dwelling Japanese older adults.

Studies have associated hearing impairment with adverse health outcomes, but the actual impact of hearing difficulty has been barely investigated. We investigated among older adults (i) the prevalence of hearing difficulty, (ii) the association of hearing difficulty with a composite outcome of dependence in activities of daily living (ADL) and death, and (iii) the population attributable risk fraction (PAF) of hearing difficulty. In 2005, a home-visit survey of 1364 Japanese older adults aged ≥65 (participation proportion=95.5%) was conducted to evaluate self-reports of hearing difficulty. Over 3 years, 99.4% of the initial sample was followed. Outcomes were measured by incidence of death or dependence in ADL. In the sample, the prevalence of hearing difficulty was 17.7% (age ≥65) and 25.7% (age ≥75). Hearing difficulty at high levels was associated with a composite outcome of dependence in ADL and mortality (adjusted odds ratio=OR and 95% confidence interval=95% CI=6.19 (1.92-19.92)) as well as with each outcome independently. Improving the hearing difficulty from high to moderate or no difficulty would reduce the composite outcome in 4.3% (age ≥65) and in 6.3% (age ≥75) of the target population. In conclusion, hearing difficulty was common, was associated with and had substantial impact on adverse health outcomes.