For people reading this who’ve suffered some form of hearing impairment, do you ever find yourself needing to work really hard to understand what’s being said to you or around you? You are not alone. The sense that listening and understanding is taxing work is typical among people with hearing impairment – even the ones that use hearing aids.
As though that wasn’t bad news enough, it may not be just your hearing that is affected, but also cognitive abilities. Contemporary research studies have established that there is a solid relationship between hearing loss and your risk of developing dementia and Alzheimer’s.
A 16-year research study of this relationship from the Johns Hopkins School of Medicine involved 639 volunteers ages 36 to 90. At the end of the research, researchers found that 58 participants (9 percent) had been identified as suffering from dementia, and that 37 participants (5.8%) had developed Alzheimer’s. The level of hearing loss was positively correlated with the odds of developing either condition. For every 10 decibel additional hearing loss, the risk of developing dementia increased 20%.
Another 16-year study with 1,984 participants revealed a similar connection between hearing loss and dementia
, but also found noticeable degradation in cognitive function in the hearing-impaired. In comparison to participants with normal hearing, those with hearing impairment developed memory loss 40 percent faster. In both studies, an even more dismal finding was that this association was not lessened by using hearing aids.
The connection between hearing loss and loss of cognitive functions is an open area of inquiry, but researchers have suggested a few theories to explain the results observed to date. One hypothesis is related to the question at the start of this article, and has been termed cognitive overload. The theory is that among the hearing-impaired, the brain tires itself out so much working to hear that it cannot focus on the meaning of the speech that it is hearing. This may bring about social isolation, which has been linked to dementia risk in other studies. A different line of thought, hypothesizes that dementia and hearing are not causally related to each other at all. Instead the theory suggests that they are both the consequence of a third mechanism. This unknown disorder could be genetic, environmental or vascular in nature.
Although the person with hearing loss probably finds these study results dismaying, there is a bright side with important lessons to be derived from them.For those who wear hearing aids, it’s crucial that you have your hearing aids tuned and re-programmed on a consistent basis. You don’t want to make you brain work harder than it has to work in order to hear. If you don’t have to work so hard to hear, you have greater cognitive capacity to comprehend what is being said, and remember it. Also, if the two conditions are connected, early detection of hearing loss may eventually lead to interventions that could delay dementia.