Longitudinal association between the hearing level and quality of life among older adults in south Korea: ascertaining the mediating effect of instrumental activities of daily living using latent growth and autoregressive cross-lagged models

Background Hearing loss is increasingly recognized as an important public health concern among older adults and is associated with decreased functional independence and quality of life. However, most previous studies have used cross-sectional designs, limiting understanding of longitudinal relationships and mediating mechanisms. This study examined the longitudinal associations among hearing level, instrumental activities of daily living, and quality of life in older adults and investigated whether instrumental activities of daily living mediated the relationship between hearing level and quality of life. Methods This descriptive longitudinal study analyzed data from 3,398 adults aged ≥ 65 years who participated in the 2020, 2022, and 2024 waves of the Korean Longitudinal Study of Aging. Hearing level, instrumental activities of daily living, and quality of life were assessed using self-reported measures. Data were analyzed using SPSS 26.0 and AMOS 26.0, and latent growth modeling and autoregressive cross-lagged modeling were applied. Results Hearing level, instrumental activities of daily living, and quality of life declined significantly over time. Latent growth modeling indicated that a higher initial hearing level was associated with higher initial levels of instrumental activities of daily living and quality of life and with a slower decline in instrumental activities of daily living. The indirect effect of the hearing level on quality of life through instrumental activities of daily living was statistically significant (β = 0.018, p < .05). Autoregressive cross-lagged modeling demonstrated a significant longitudinal indirect pathway from hearing level at Time 1 to quality of life at Time 3 through instrumental activities of daily living at Time 2. Conclusions Hearing level was longitudinally associated with quality of life, and instrumental activities of daily living significantly mediated this longitudinal association among older adults. These findings suggest that integrated interventions combining hearing management with support for instrumental activities of daily living may be beneficial for promoting healthy aging and quality of life among older adults.