Declines in hearing or vision have been linked to dementia in the past, but combined losses in these two senses are associated with a greater risk of both dementia and Alzheimer’s — even if the impairment to both senses is relatively minor, the AARP reports.
That’s the conclusion from studies reported on at the Alzheimer’s Association International Conference 2019 last month in Los Angeles.
In one study, researchers from the University of Washington School of Public Health in Seattle explored the connection between sensory impairment and dementia in a group of more than 2,000 people age 75 and older. Participants were cognitively healthy at the start of study and were followed for seven years.
The study showed that people who were either visually or hearing impaired had an 11 percent increased risk of developing dementia overall and a 10 percent greater risk for Alzheimer’s disease specifically. But having both hearing and vision loss put people at a much greater risk for cognitive deterioration.
“People with combined vision and hearing impairments had an 86 percent increased risk for all-cause dementia and a more-than-two-times increased risk for Alzheimer’s dementia,” according to Phillip Hwang, a doctoral epidemiology student at the University of Washington and lead author of the study.
Hwang explained that before this latest research was released, most studies had focused on a single sensory impairment. “But a greater proportion of older adults experience more than one sensory impairment as they age. We wanted to understand the effect of having multiple sensory impairments on dementia.”