Older adults who have hearing and/or vision impairment are also more likely to have cognitive impairment, according to a study of more than 5.4 million participants aged 65 years and older, according to a study published in the Journal of Alzheimers Disease Reports.¹

Researchers from the University of Toronto in Canada, carried out a secondary analysis of data from 10 consecutive waves of the American Community Survey (ACS) from 2008 to 2017. A total of 5,405,135 participants aged 65 years or above, living in the community or institutionalized, were included in the study. More than half were women (56.4%). All participants were asked to respond (yes/no) to questions regarding cognitive impairment, hearing impairment, and vision impairment. A family member provided the answers when the participant could not. The objective of the study was to examine the association between vision impairment, hearing impairment and dual sensory impairment with cognitive impairment among older adults.

Among those with cognitive impairment, 22% were found to have only hearing impairment, ~ 10% had vision impairment, while 16% had both hearing impairment and vision impairment. Among those who were not cognitively impaired, nearly 11% had hearing impairment, 3% had vision impairment and less than 2% had dual sensory impairment.

Around 52% in the cognitive impaired group had no sensory impairment; 84.3% in the no cognitive impairment group did not have any sensory impairment. Analysis of data showed that the risk of cognitive impairment was increased 2-folds among participants who only had a hearing impairment with odds ratio of 2.66. Those who had a vision impairment alone tripled their risk of cognitive impairment with OR of 3.63. However, the probability of cognitive impairment was 8 times higher in those who had dual sensory impairment (OR 8.16).

Compared to those who did not have any sensory impairment, a dose-response association was noted in participants aged 65-74 years for those with hearing impairment alone (OR   3.45), vision impairment alone (OR  5.16) and dual sensory impairment (OR  14.24). 

The prevalence of dual sensory impairment increased from 1.5% in participants aged 65-74 years to 2.6% in those aged 75-84 years, whereas in subjects aged 85 years and older, the prevalence further increased to 10.8%. The level of education also had an effect on the prevalence of sensory impairment. High school dropouts had a higher prevalence of dual sensory impairment (6.3%) compared to those who were either high school (3.1%) or university graduates (1.85%).

This study has demonstrated an association of hearing and vision impairment with cognitive impairment. The prevalence of hearing and vision impairment was higher in persons with cognitive impairment. The association was more robust when both sensory impairments were coexistent, even after adjusting for sociodemographic parameters. Social isolation due to sensory impairment may hasten the process of cognitive decline.

Being an observational study, it has only shown an association and does not dwell on the causes behind the link between the two. Older adults, particularly those in the 65-74-year age group, with hearing and/or vision impairment must be carefully evaluated for cognitive impairment to assess possibility of early intervention (such as hearing aids, cataract surgery) and manage both conditions concurrently to prevent further deterioration. Efforts must also be made to connect them to the community in order to alleviate loneliness or social isolation.

Reference

1. Fuller-Thomson, E, et al. The association between hearing impairment, vision impairment, dual sensory impairment, and serious cognitive impairment: findings from a population-based study of 5.4 million older adults. J Alzheimers Dis Rep. 2022;6:211-222.