Profiles of social isolation and loneliness as moderators of the longitudinal association between uncorrected hearing impairment and cognitive aging.

Abstract

Hearing impairment affects a growing number of older adults and is linked to cognitive decline. This study investigated whether profiles of social isolation and loneliness (e.g., non-isolated but lonely) moderate the association between hearing impairment and cognition over time across domains. Using longitudinal data from waves 1-9 of the Survey of Health, Ageing, and Retirement in Europe (SHARE), we analysed 33,741 individuals (Mage = 61.4, SD = 8.6) using multilevel models accounting for both inter-and intra-individual variability. Results showed that both higher levels and worsening self-reported hearing impairment were associated with lower cognitive performance and steeper decline in episodic memory (immediate and delayed recall) and executive functioning (verbal fluency). Notably, profiles combining social isolation and/or loneliness were linked to lower cognitive performance across domains. Furthermore, for the "non-isolated but lonely" profile hearing impairment was more strongly and negatively associated with episodic memory decline compared to the non-isolated and not lonely profiles. A separate multivariate model confirmed that the moderating role of social isolation and loneliness profiles differed across cognitive domains. Specifically, among individuals in the non-isolated but lonely group, the negative association between hearing impairment and cognition was strongest for episodic memory compared to executive functions. These findings underscore the importance of considering both sensory and psychosocial factors in cognitive aging. Addressing hearing impairment alongside loneliness-even in socially integrated individuals-may be crucial for promoting cognitive health in later life.