Older adults who experience both vision and hearing loss may be at higher dementia risk, according to the new research by Kangwon National University Hospital in South Korea.
Korean researchers collected data from more than 6,500 people between the ages of 58 and 101 for 6 years via self-reported questionnaires, as well as through cognitive testing every 2 years. The researchers have found that 7.6% of those who have reported both vision and hearing loss had dementia at the start of the study, while another 7.4% of participants developed dementia within six years.
Meanwhile, only 2.4% of people with only vision or hearing loss had dementia at the beginning of the study, and only additional 2.9% of the study participants developed dementia by the study’s end. Adjusting for external factors that influence dementia, such as sex, education, and income, the researchers estimate that people experiencing both vision and hearing loss are twice as likely to develop dementia as people who experience only one of the impairments.
“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,” said study author JinHyeong Jhoo, M.D., Ph.D., of Kangwon National University School of Medicine in Chuncheon, Republic of Korea. Jhoo added, “But our study results suggest losing both may be of particular concern.”
The researchers wonder if the dual impairment has a more significant impact on brain’s ability to compensate for the lost senses. Commonly, people with impaired vision learn to rely more on their hearing, while people with hearing loss tend to depend on their vision and visual clues to compensate. The dual loss is thought to increase the risk of social isolation, and depression, which contributes to heightened risk of dementia.