A study by researchers at the Johns Hopkins Bloomberg School of Public Health found that older adults with severe hearing loss were more likely to develop dementia, but dementia was lower among study participants who used hearing aids.
What did we learn?
Previous studies have also looked at the relationship between hearing loss and dementia. A study published in 2012 Compared to people with normal hearing loss, people with mild hearing loss are twice as likely to develop dementia, those with moderate hearing loss are three times more likely to develop dementia, and those with severe hearing loss are five times more likely to develop dementia. In fact, hearing loss is estimated to account for 8 percent of dementia worldwide—more than any other modifiable risk factor for dementia, according to a 2015 study. Lancet Commission on Dementia Prevention, Intervention and Care.
But the researchers of this latest study, the findings were Published in research letter Previous studies, published in the peer-reviewed journal on Jan. 10, are limited because they are “susceptible to selection bias” — using self-reported data that may not provide an accurate picture of hearing loss and dementia at the national level.
“Rather than relying on objective, self-reported hearing loss, this study used objective, audiometric hearing tests. We used data from a large representative population of adults in the US,” study leader Alison Huang, a senior research associate at the Johns Hopkins Center for Cochlear Hearing and Public Health, said in an email to Yahoo News.
The study, funded by the National Institute on Aging, analyzed national data from the National Survey of Health and Aging Trends, which has been ongoing since 2011.
“The National Survey of Health and Aging Trends collects data on home visits, which make it easier for more vulnerable populations, such as adults over 90 and adults with disabilities, to participate compared to a clinic that only treats people who have the ability and means to reach clinics.” Huang said.
The analysis of this study included 2,413 individuals, half of whom were over 80, and “clearly demonstrated a link between hearing loss and dementia.” According to the press release from Johns Hopkins. The prevalence of dementia among participants with “moderate/severe hearing loss” was 61 percent higher than among participants with normal hearing.
Good news?
The good news is that hearing aids may have a beneficial side effect. The study found that among 853 participants with moderate to severe hearing loss, “the use of hearing aids was associated with 32% less dementia.”
“We are encouraged by the association between hearing aid use and lower dementia prevalence, which supports public health measures to improve access to hearing services,” Huang told Yahoo News.
She added that more work from randomized trials is needed to properly test the effects of hearing aids on cognition and dementia. The ACHIEVE (Aging and Cognitive Health Evaluation in the Elderly) trial, also funded by the National Institute on Aging, will test the effects of hearing loss treatment on cognition and dementia, and results from that trial will be available later this year, Huang said.
One-third of the elderly have hearing loss, and the risk of hearing loss increases with age. According to the National Institute on Aging.
Dr. Frank Lynn, one of the leaders of the ACHIEVE trial; He offered several possible reasons The relationship between hearing loss and cognitive decline. Hearing loss “can make the brain work harder,” at the expense of memory systems; Hearing loss can cause the brain to “slow down”. Another possible reason is that hearing loss makes people socially isolated, which affects brain health.
“If you can’t hear well, you may not be able to get outside as much, so the mind is less busy and less active,” says Lin.