Association of Loneliness With the Incidence of Disability in Older Adults With Hearing Impairment in Japan

IMPORTANCE Loneliness is suggested to negatively affect physical and mental health and influence the development of disability; however, a consensus on the relationship between loneliness and disability has not been reached. Age-related hearing impairment worsens the daily-life activities of older adults, and the association between loneliness and the incidence of disabilitymay be influenced by hearing impairment. OBJECTIVE To examine the association between loneliness and the incidence of disability among older adults stratified by hearing impairment. DESIGN, SETTING, AND PARTICIPANTS This prospective observational cohort study included 5563 community-dwelling adults 65 years or older who participated in functional health examinations in Tokai City, Aichi Prefecture, Japan, between September 2017 and June 2018. Data analysis was conducted from August 2022 to February 2023. MAIN OUTCOMES AND MEASURES Cox proportional hazards regression modelswere used to examine the association between loneliness and the incidence of disability stratified by hearing impairment. RESULTS Among the 4739 participants who met the inclusion criteria (mean [SD] age, 73.8 [5.5] years; 2622 [55.3%] female), 3792 (80.0%) were without hearing impairment and 947 (20.0%) were with hearing impairment. Of those who reported experiencing loneliness, 1215 (32.0%) were without hearing impairment, and 441 (46.6%) were with hearing impairment. After 2 years, the number of individuals with disabilities was 172 (4.5%) without hearing impairment and 79 (8.3%) with hearing impairment. Cox proportional hazards regression analysis showed no statistically significant association between loneliness and the incidence of disability in a model adjusted for potential confounding factors among community-dwelling older adults without hearing impairment (hazard ratio, 1.10; 95% CI, 0.80-1.52). Among community-dwelling older adults with hearing impairment, a model adjusted for potential confounding factors showed a statistically significant association between loneliness and the incidence of disability (hazard ratio, 1.71; 95% CI, 1.04-2.81). CONCLUSIONS AND RELEVANCE This cohort study found that the association between loneliness and the incidence of disability was moderated by the presence or absence of hearing impairment. Hearing impairment is the most common symptom of geriatric syndromes, showing that among the various risk factors, loneliness may require special attention in the prevention of disability in people with hearing impairment.