It has been known for some time that individuals with hearing loss and particularly those who develop the loss later in life, have an increased risk of developing cognitive decline and dementia.  

There has also been a general sense within the community of hearing health professionals that the use of hearing aids and cochlear implants in conjunction with a treatment plan can slow the progression of cognitive decline and dementia long term.

A report published December 5, 2022, in the Journal of the American Medical Association - Neurology provides evidence to support that conclusion.

Dr. Rebecca Younk, chief audiologist and owner of Associated Hearing Care, has seen the simultaneous presence of dementia and hearing loss in the patients she treats in New Richmond and Hudson long before the study was published.

“I’ve been doing this for 20 years and a lot of people minimize their hearing loss and the impact of hearing. Often, they don’t realize what they’re missing, what they’re not hearing. It’s often other people who realize what they are missing,” Younk said. “It’s exciting to see that intervention is making a significant difference.”

The scope of the initial data collection was comprehensive. It looked at all of the randomized clinical trials or observational studies published as full-length articles in peer-reviewed journals relating to the effect of hearing interventions on cognitive function, cognitive decline, cognitive impairment and dementia in patients with hearing loss in the PubMed, Embase and Cochrane databases from inception to July 23, 2021.

A total of 3,243 studies were screened; 31 studies (25 observational studies and 6 trials) with 137, 484 participants were included. Meta-analysis of 19 (15 observational studies and 4 trials) of those studies yielded significant results. 

“The study published in December showed that the use of hearing devices was associated with a 19% reduction of long-term cognitive decline and dementia and actually a 3% improvement in cognitive test scores in the short term,” Younk said.

Younk explained there are two fundamental causes of dementia, genetic predisposition and environmental causation. 

So far, science has been unable to crack the genetics of dementia.

However, when it comes to environmental reasons for hearing loss, those are things we can control with our actions and decisions and the application of technology. For example, we can protect our hearing by limiting our exposure to harmful noise, taking care of our overall health by eating better and exercising, and by acting early at any signs of hearing loss. 

“We now understand that our health as a whole impacts our ability to hear, diabetes, exercise, weight, diet, they are all connected,” Younk said. “Exercising everyday helps not only our weight and our heart, it also helps our ears and our hearing.”

There are three working theories about how hearing loss contributes to cognitive decline and dementia.

1. Scientific studies show that hearing loss causes the temporal lobe in the brain to shrink. This applies primarily to people who develop hearing loss later in life, not necessarily to people who are born deaf. 

2. Hearing loss makes it difficult to communicate with loved ones, friends and people in a person’s everyday work and social environment. That can lead to mental health issues including social isolation, loneliness, depression and those are all risk factors for developing dementia. 

3. Poor hearing taxes your brain. If you have to work harder to pick out what people are saying, your brain has to work harder to fill in the gaps. Taxing your brain can come at the expense of other areas of your brain and cause a chain reaction.

Our senses work together to interpret what is going on around us and then communicate that information to our brain. Take one away and other senses have to compensate and our brain has to work harder to fill in the gaps

“We’re even seeing that people with hearing loss are more likely to fall because their brains are being taxed, they’re paying more attention to filling in gaps than they are to walking. A fall can lead to more hospitalization and the chain reaction continues,” Younk said.

Up to 90% of individuals with hearing loss have some sort of nerve damage.

“The cochlea, where the sensory part of our nerves related to hearing are located, is damaged. The brain is essentially receiving a damaged sound which it has to sort out,” Younk explained.

Younk believes combining the right technology with the right techniques and an effective treatment plan can significantly mitigate the impact of hearing loss on cognitive decline and dementia.

“When we’re using any device to augment the sound in your environment (hearing aid or cochlear implant), we’re still working with the damaged cochlea, the damaged nerve system. So we have to program that hearing aid or [cochlear implant] to work within that damaged system to send the best possible clear sound to the brain so the brain can interpret it as well as possible,” Younk said.

The brain can also be retrained and that’s where the treatment plan comes in. 

The better the signal to the brain, the better the brain can retrain itself.

“We work with the individual with hearing loss as well as their family to give them tips and tricks on how to better communicate, to make sure the auditory signal is as clean and clear as possible and the environment and the hearing device are working together effectively,” Younk said.

Younk believes people undervalue their hearing and should do more to actively protect it and test it regularly as a part of their preventive care plan. She also recommends early intervention if you notice a loss, talking to a hearing professional to find ways to slow further progression. Employing early intervention not only slows the progression of hearing loss, it gets people into the healthy habit of using their hearing aid.

“Let’s say they develop hearing loss at 60 and they realize they do need to wear their hearing aids now. That’s good because in the case that they are more genetically predisposed to developing dementia later in life, they are more likely to be in the habit of wearing their hearing aids once that dementia begins to set in, it becomes routine,” Younk said. “The most important thing I want people to know is how important connections are between you and your loved ones. Hearing is a big part of that. It’s difficult to communicate if hearing is a barrier. Take care of your hearing so you can take care of those connections.”

Dr. Rebecca A. Younk

Younk  is the new owner and chief audiologist at the Beltone locations in New Richmond and Hudson. Younk graduated with a bachelor’s degree in communication disorders in 1997 from Truman State University, her master’s in audiology from Washington University in St. Louis in 1999 and her doctor of audiology from the University of Florida in 2007.

Younk believes in the holistic approach to hearing care for her patients, finding the right tools, techniques and products that will provide the optimal outcome to make sure grandparents hear their grandchildren, working adults excel at work and children benefit from the necessary sounds around them to grow to their full potential. 

To learn more about Younk, visit Associated Hearing Care at associated-hearing.com.