A Connection Between Hearing Loss and Dementia?

Contact our audiologists or ENT physician today to learn more about the possible link between Hearing Loss and Dementia, and about how hearing aids may be able to help.

Recently, a growing body of research has shown that a strong link may exist between hearing loss and dementia, the chronic decline in mental abilities such as thinking, reasoning, and memory. It is a disorder affecting over 50 million people worldwide and becomes more common with aging.

Hearing loss affects over 27 million Americans over the age of 50. It’s typically caused by damage to the tiny hair cells within the cochlea, the organ in the deepest part of each ear that “translates” sound waves into nerve messages to the brain. Damage to the cochlea, be it from age, noise exposure, genetics, etc., can lead to a damaged message quality being sent to the brain via the hearing nerve. These damaged messages to the brain can make soft sounds much harder to hear, can make even loud sounds unclear, and can cause speech to sound muffled.

Research from Frank Lin, M.D., Ph.D., and others at Johns Hopkins followed 639 adults for 12 years. Their findings suggest that even low levels of hearing loss may increase your risk of developing dementia: a mild hearing loss can double dementia risk, moderate loss can triple risk, and people with a severe hearing impairment may be five times more likely to develop dementia.

While there is no concrete proof yet on how hearing loss affects brain function, some strong theories have emerged. fMRI scans have shown that if the brain receives a damaged message via the nerves — whether a result of poor hearing or the presence of background noise that interferes with good hearing — regions in the brain related to reasoning, decision making, and memory (as opposed to speech understanding) are activated. This activation can “overload” them and make these areas work harder in order for the listener to comprehend what is being said. The most recent research, still unpublished, has shown that if the nerves responsible for hearing in the inner ear do not send enough information to the brain, certain parts of the brain develop ‘empty spots’ or ‘vacuoles’. 

Treating the hearing loss, such as through the use of hearing aids and cochlear implants, may improve cognition and may lessen the risk of developing dementia if addressed early on. A 2015 study from Dr. Isabelle Mosnier studied cognitive improvement in over 100 older adults with deafness in at least one ear after being fit with a cochlear implant, which stimulates the auditory nerve with an electrical current. After one year, 80 percent showed cognitive improvement. They also reported less depression-a symptom that is common in those with dementia and hearing loss.

“Hearing aids have been shown to be one of the most effective ways to prevent dementia, and can even help improve cognitive function in people with mild dementia.”

-Dr. Stan Phillips

The bottom line: Hearing loss needs to be addressed as early as possible. Improving your communication ability, through the use of communication strategies or devices like hearing aids, may also lead to improvements in your cognition and mental health, as well as reduce your risk for developing dementia. Here at South Lake Hearing and Tinnitus Center, our ENT and Audiology doctors are ready and able to address your concerns and work with you to improve your quality of life by improving your communication skills.