Age-related hearing loss should be taken seriously, according to Dr. Rita R. Chaiken, audiologist and past president of the Academy of Doctors of Audiology.
“Ongoing studies of patients with even mild age-related hearing loss suggests shrinkage and other re-organization changes in the cortical brain areas,” said Chaiken, who consults and lives in Atlanta. “In addition to hearing sounds, these areas may also be used for higher-level decision-making — underscoring the importance of early hearing screening for people over the age of 60.”
Aging and hearing loss can lead to a change in attitude. The more often people around us seem to “mumble,” the less we care about what we hear (or how we hear). This can lead to quality of life concerns. One premise is if the brain is struggling to cope with degraded sounds, then there is a decrease in overall cognitive function, according to a 2017 article from the Hearing Health Foundation.
In general terms, it’s suggested that the brain’s processing power is bogged down from struggling to hear, which can ultimately create an overload — one “gives way” to the other. In short, “the cerebrum, which is not exclusive to processing sound, plays a role in memory,” states a Hearing Health Foundation article.
And hearing problems are commonplace among older adults. Dr. Frank R. Lin, director of the Cochlear Center for Hearing and Public Health at the Johns Hopkins Bloomberg School of Public Health, estimates that nearly two-thirds of all adults 70 years and older have a clinically significant hearing loss.
According to the World Health Organization, “Unaddressed hearing loss poses an annual global cost of US$ 750 billion, [while] interventions to prevent, identify and address hearing loss are cost-effective and can bring great benefit to individuals.”
When further studies continue to show that hearing loss slows down mental processes — and that improving hearing eases or helps reverse this decline — the gains could be profound for aging adults, claim the experts.
“Our goal as audiologists is to provide a means to get people to engage in communication,” said Dr. Helena Solodar, audiologist and co-founder of Audiological Consultants of Atlanta. “Sometimes as clinicians, we’re aware of something before it hits the research scene,” she said. “For years and years, we’ve known that our auditory system has played an extremely important role in cognition.”
Like many clinicians, Solodar and Chaiken say they see a tremendous improvement in patients with hearing aids and other hearing-assistive devices. The ability to be more engaged with friends and family, feelings of less isolation and even wanting to go out and return to their former life are benefits described by many of her patients, Solodar says, and adds that hearing loss and its connection to signs of dementia is a hot topic.
The benefit-cost ratio is obvious. Dementia is already a huge U.S. financial burden, which ranges from $159 billion to $215 billion annually. It’s costlier to the nation than either heart disease or cancer, according to a 2013 RAND Corporation study.
Dr. Lin’s work is known worldwide. His research is focused on studying the interface between hearing loss and its consequences, and aging.
“Over the next forty years, prevalence rates of dementia are projected to double every twenty years because of the aging of the world population,” states Lin as lead author in a 2014 paper, “Hearing Loss and Dementia — Who’s Listening.”
The potential public health impact of hearing loss in the context of dementia is substantial, especially given the high worldwide prevalence of hearing loss in older adults — and the ready availability of existing hearing rehabilitative interventions, said Lin, who co-authored the paper with Marilyn Albert, Director of Cognitive Neuroscience and Johns Hopkins Department of Neurology professor.
Lin is currently working with conducting the Aging Cognition and Health Evaluation (ACHIEVE) study. This research will help determine if existing hearing rehabilitative interventions can reduce the rate of cognitive decline (memory and thinking skills) in older adults. The work is of substantial public health importance.
While links between compromised hearing and cognitive decline seem compelling, this research is still relatively new. Many questions remain, but there are theories about how hearing loss may affect the brain and its cognitive abilities.
Lin explained that hearing has two very basic properties. “The cochlea [the main organ for hearing and resides in our ear] takes in a very complex sound and converts it into a signal with accurate fidelity. That signal goes to the brain, and the brain decodes the signal.”
He said that it’s a very fundamental process. [It requires] “encoding in the cochlear and decoding in the brain.”
In a published 2014 study, Lin and his colleagues show the brain becomes smaller with age, and the shrinkage seems to be fast-tracked in older adults with hearing loss. The researchers were from Johns Hopkins and the National Institute of Aging.
Such findings add to a growing list of health consequences associated with hearing loss, including falls and hospitalizations — leading to diminished physical and mental health. And even though correlation doesn’t imply causation, the dementia and hearing research is worth looking at. But until further work in the area of hearing loss (as well as its effect on cognitive abilities), nothing is for sure.
Audiologists, nurses and medical doctors remind us that getting our hearing checked is a critical part of healthy aging.
Lead photo courtesy of Pixabay.