DEPRESSION AND HEARING LOSS GO HAND IN HAND
A recent study by the National Institute on Deafness and Other Communication Disorders (NIDOCD) provided numerical confirmation of a long suspected and logical connection between hearing loss and depression. Hearing loss creates communication difficulties which can cause embarrassment, frustration, fatigue, and can lead one to retreat socially and become isolated. Isolation in turn creates feelings of loneliness, misunderstanding, and depression. Dr. Chuan-Ming Li, the study’s author, noted that over 11% of adults with “a little hearing trouble or greater hearing impairment” suffered moderate to severe depression compared to only 5% of the population with “excellent” hearing. That’s more than double the incidents of depression when hearing loss is present. Dr. Li acknowledges that the study does not establish a cause-and-effect relationship. But Dr. Sergei Kochkin of the Better Hearing Institute observes that 9 out of 10 people reported a significant improvement in quality of life after acquiring hearing aids and thorough professional services.
HEARING LOSS ABOUNDS IN CANADIAN POPULATION
Canadian Health Measures Survey of 2012 and 2013 indicate that:
- 20% of adults (or 1 in 5) aged 19 to 79 had at least mild hearing loss in one or both ears.
- Prevalence of hearing loss increases with age: 47% of adults aged 60-79 experience hearing loss compared to 16% of adults aged 40-59 and only 7% of 19-39 year olds.
- Two thirds of adults over 60 with hearing loss experienced trouble in both ears compared to half of the 40-59 year olds.
Strikingly, the survey reported that “The majority of Canadians with measured hearing loss were not aware they had any hearing problems. About 70% of adults and 83% of children or youth with measured hearing loss did not report any diagnosis of hearing problems by a health care professional.” In other words, despite receiving a regular health check-up from medical professionals, 70% of adult Canadians with hearing loss left their doctor’s offices undiagnosed. Therefore, a thorough hearing evaluation by a hearing healthcare professional should be specifically and proactively sought out in order to identify the existence of hearing loss and the appropriate treatment options. Hearing should be checked annually after the age of 60.
HEARING LOSS TAKES A TOLL ON BRAIN FUNCTION
Researchers at the Brain and Behavior Laboratory at the University of Colorado studying neuroplasticity and the impact of age-related hearing loss on the brain are finding that when hearing loss is present, the “hearing areas of the brain shrink” and the brain then recruits areas of the brain typically used for higher decision-making functions just to processes sound impulses. This form of compensation increases the overall load on the brain and may contribute to cognitive decline. Dr. Anu Sharma of the lab, reports, “Compensatory brain reorganization secondary to hearing loss may also be a factor in explaining recent reports in the literature that show age-related hearing loss is significantly correlated with dementia.” Further she notes, “Given that even small degrees of hearing loss can cause secondary changes in the brain, hearing screenings for adults and intervention in the form of hearing aids should be considered much earlier to protect against reorganization of the brain.”
HEARING LOSS AND DEMENTIA LINKED
Although the reason for the link is as yet unclear, a recent Johns Hopkins and National Institute on Aging study shows that seniors with hearing loss are significantly more likely to develop dementia over time than those with normal hearing. Researchers say these findings “could lead to new ways to combat dementia, a condition that affects millions of people worldwide and carries heavy societal burdens.”
Further, they suggest a common pathology may underlie the two conditions, or that the strain of “decoding sound” over the years puts undue strain on the brain leaving them more vulnerable to dementia. Other speculation includes the social isolation that often results from hearing loss as a factor that could exacerbate dementia and other cognitive disorders. “Whatever the cause,” the school reports, “their finding may offer a starting point for interventions — even as simple as hearing aids — that could delay or prevent dementia by improving patients’ hearing.”
HEARING AIDS MAY HELP POSTPONE OR PROTECT AGAINST COGNITIVE DECLINE
While the link between hearing loss and cognitive decline including dementia has been established, causality isn’t yet clear. A new study, however, suggests that wearing hearing aids may help postpone or possibly protect against future cognitive problems.
The Johns Hopkins study included just over 250 people from Maryland with an average age in the mid 70s. Most people in the study had mild, moderate or severe hearing loss and underwent testing on memory, learning, and processing speed and attention, 3 times over a period of 20 years (first in the early 90s, then in the late 90s, and an intensive cognitive test in 2013).
The study found that all participants declined over the years, but those with moderate to severe hearing loss who reported not wearing hearing aids showed the worst decline in cognitive function. In fact, participants who wore hearing aids showed only a slightly greater decline than participants with normal hearing.
Jennifer Deal, the study’s lead author reports, “This study is important because it focuses on a risk factor that is amenable to intervention in later life and could potentially postpone cognitive decline.”
Johns Hopkins is launching another 5 year study to more specifically look at the impact of wearing hearing aids on cognitive abilities, and whether treatment for hearing loss can prevent or postpone cognitive decline.