By now you have probably heard that hearing loss puts you at greater risk for developing dementia and seen the ads that proclaim, “GET HEARING AIDS OR RISK GETTING DEMENTIA!” or “KEEP YOUR BRAIN HEALTHY WITH HEARING AIDS!” Where did all this hype come from and is there any truth to it?
Dr. Frank Lin, an otologist and epidemiologist at Johns Hopkins University in Baltimore put out a study in 2011 and 2013. He was able to show that individuals with hearing loss were 24% more likely than those with normal hearing to see their cognitive abilities diminish. In fact, for every 25 decibels of hearing loss, the individual scored 7 years older on cognitive related task. Additionally, he found that for every 10 decibels of hearing loss, the risk for developing dementia increased by 20%. He was quick to point out that just because you have an increased risk due to hearing loss, does not mean you will develop dementia.
But what causes the link between hearing loss and dementia?
Researchers have lumped the cause into 4 theories. The first is that vascular disease is the culprit as that is linked to both increased risk of hearing loss and dementia. This theory has largely been discredited. The second theory is that the hearing loss creates a “cognitive load” and leaves less resources for the brain to complete cognitive tasks. The third is that the hearing loss may cause structural changes in the brain as it has been shown that individuals with hearing loss have less gray matter. Lastly, sensory deprivation may contribute to the deterioration of the brain.
Can cognitive decline be reversed with hearing aids?
Isabelle Mosnier of Assitance Publique Hopitaux de Paris in France, studied a group of individuals who received a cochlear implant and greater than 80% showed significant improvement in cognitive tasks one-year post implant. A new study published in October 2018 in the Journal of the American Geriatric Society tracked 2040 individuals between 1996-2014. Researchers monitored the rate of cognitive decline before and after getting hearing aids. The results: the hearing aids did not halt or reverse cognitive decline, however, hearing aids slowed the rate of decline by 75%. Additionally, Dr. Lin is conducting a long-term study set to be completed in 2020. He hopes to answer the question on whether hearing aids can be used as a preventable treatment toward dementia.
According to the Centers for Disease Control and Prevent, hearing loss is the third most chronic physical condition in the United States and is more prevalent than diabetes or cancer. It is recommended that a hearing screening should be done during an annual exam starting at the age of 21 years and every 3-5 years after that. For individuals who do not pass the screening, a full diagnostic hearing test should be done by an audiologist. Depending on the type of hearing loss found, hearing aids may be an option for treatment. To schedule a hearing test, Flex Audiology located in Greendale Indiana is now accepting new patients.