Numerous studies have looked at the relationship between hearing loss and dementia as well as visual impairment and the development of cognitive decline. New research has found the chances of developing dementia are significantly higher if an individual has both hearing and vision loss.
The Relationship Between Vision and Hearing
“Dual sensory impairment in older adults and risk of dementia from the GEM Study,” published in the July issue of Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring determined that the risk of developing dementia increases by 86 percent for individuals who have both hearing and visual impairment.
According to Phillip H. Hwang, the lead study author, “Evaluation of vision and hearing in older adults may predict who will develop dementia and Alzheimer’s. This has important implications for identifying potential participants in prevention trials for Alzheimer’s disease, as well as whether treatments for vision and hearing loss can modify risk for dementia.”
Vision and hearing loss are both progressive conditions that worsen with age. About 33 percent of people over the age of 70 experience hearing loss while 18 percent have a loss of vision. The combination of hearing and vision loss together is known as dual sensory impairment.
Researchers suspect there is a correlation between how these conditions advance and patients’ loss of functionality.
There are two schools of thought when it comes to how these conditions can lead to dementia. One hypothesis is that hearing and vision loss are the result of the same physical process that causes dementia. The second theory is that vision and hearing loss lead to an increase in depression and social isolation as well as a decrease in physical activity, which may lead to the development of dementia.
Old Data Is New Again
Hwang and his team analyzed data previously collected by a double‐blind randomized‐controlled trial investigating if Ginkgo biloba could prevent dementia in older people. The Gingko Evaluation of Memory (GEM) study recruited individuals over the age of 75 with normal cognitive function. They followed participants for eight years, collecting data from self-reported questionnaires about their hearing and vision as well as follow-up exams assessing their development of dementia.
A total of 2051 individuals’ data was reviewed for this new study. Of those participants:
- 72 percent reported no vision or hearing loss
- 15 percent reported vision loss
- 8 percent reported hearing loss
- 5 percent reported both (dual sensory impairment)
The researchers found that people with both hearing and vision loss were twice as likely to develop dementia compared to those without any impairment. In addition, their data revealed the following likelihoods for developing dementia:
- 14 percent of those who reported no vision or hearing loss developed dementia
- 17 percent of those who reported a single impairment developed dementia
- 29 percent of those who reported dual sensory impairment developed dementia
It is important to note that the increased risk of developing dementia with dual sensory impairment was only slightly related to the severity of the two conditions.
According to Hwang, “Further research is needed to characterize the exact role of sensory impairments and whether treatments that improve sensory function, such as surgery or sensory aids, devices, and prostheses, can modify this risk.”
This research does point to the importance of preventing and treating vision and hearing loss in older people, especially if it can prevent the onset of dementia.
To learn more about treating your hearing loss or to schedule an appointment with an experienced hearing professional, contact Evergreen Speech & Hearing Inc.