These Health Issues Double Your Dementia Risk, Says Study
Older people who have impairments of both sight and hearing may be at an increased risk of dementia, a new study has found. "Dementia is not a specific disease but is rather a general term for the impaired ability to remember, think, or make decisions that interferes with doing everyday activities," says the CDC, noting that "it is not a part of normal aging." Read on to see why your sign and hearing can be predictive factors—and to ensure your health and the health of others, don't miss these Signs Your Illness is Actually Coronavirus in Disguise.
"Coexisting Visual and Hearing Impairments Facilitate Dementia Prevalence"
In findings published April 7 in the journal Neurology, researchers from South Korea analyzed 6,250 adults, aged 58 to 101, who reported whether they had visual or auditory impairment on a questionnaire. The participants were followed for six years, with researchers checking in every two.
Among the study participants, 932 had normal sensory function, 2,957 had single sensory impairment (SSI: sight or hearing), and 2,631 had dual sensory impairment (DSI). The researchers found that having DSI was associated with a higher prevalence of dementia when the study began, and a greater risk of developing it during the study's six-year duration.
"Our results suggest that coexisting visual and hearing impairments facilitate dementia prevalence, dementia incidence, and cognitive decline, but visual or hearing impairment alone do not," the researchers wrote. "Visual and hearing impairment may lead to dementia or cognitive decline independent of Alzheimer's pathology."
The study may help doctors better screen their patients for signs of dementia. "Depending on the degree of hearing or vision loss, losing function in your senses can be distressing and have an impact on your daily life," a study co-author said. "But our study results suggest losing both may be of particular concern."
What's the Connection?
The risk factors for dementia are poorly understood. But other studies have found a connection between hearing impairment alone and dementia.
A previous study done at Johns Hopkins found that hearing loss alone doubled the risk of developing Alzheimer's disease, one of more than 100 conditions grouped under the umbrella term of dementia.
Experts aren't sure why losing hearing or sight—or both—might cause the brain to decline as well, but they have developed theories. A 2017 review of studies published in the journal Laryngoscope Investigative Otolaryngology outlined some: "Hearing loss increases the cognitive load, diverting cognitive resources to auditory processing at the expense of other cognitive processes such as working memory," the researchers wrote. "Another hypothesis is that hearing loss leads to social isolation, which has been shown to contribute to dementia. The third prominent explanation is that there is a common cause to both diseases and that hearing loss is the early manifestation of the underlying pathology. It is also possible that these proposed mechanisms are not mutually exclusive, and decline in one pathway consequentially affects the others."
Regular Screening Advised
Experts urge older adults to have their sight and hearing tested regularly and to wear glasses or hearing aids if needed. Older adults are also advised to undergo screening for dementia on a regular basis. Although there is no cure for dementia-related illnesses like Alzheimer's, getting treatment early can slow progression of the disease. Don't miss these Sure Signs You're Getting Dementia, According to Doctors.