For those of you who have suffered some form of hearing impairment, do you ever find yourself needing to work very hard to understand what’s being said to you or around you? You are not the only one. The sensation that listening and understanding is taxing work is common among individuals with hearing loss – even those that wear hearing aids.
This frequent sensation may impact more than your hearing; it may also influence your cognitive abilities and your memory. Hearing loss significantly raises your chance of contracting Alzheimer’s or dementia according to recent scientific studies.
A 16-year research study of this relationship from the Johns Hopkins School of Medicine involved 639 participants ages 36 to 90. The researchers found that at the conclusion of the research project, 58 of the participants (9%) had developed dementia, and 37 (5.8 percent) had been diagnosed with Alzheimer’s. The degree of hearing loss was positively correlated with the probability of developing either condition. For every 10 decibel further hearing loss, the risk of developing dementia went up by 20 percent.
In a similar research study, surveying 1,984 participants, researchers found a similar connection between hearing loss and dementia, but they also noted that the hearing-impaired experienced measurable decreases in their cognitive capabilities. In comparison to participants with normal hearing, those with hearing impairment developed memory loss 40% faster. A far more astonishing finding in each of the two research studies was that the connection between dementia and hearing loss held true even if the participants wore hearing aids.
The connection between hearing impairment and loss of cognitive functions is an open area of research, but researchers have suggested a few theories to explain the results seen thus far. One explanation is based on the question at the beginning of this article, and has been given the name cognitive overload. The theory is that among the hearing-impaired, the brain tires itself out so much trying to hear that it cannot concentrate 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. Another idea is that neither hearing loss nor dementia cause the other, but that they are both related to an as-yet-undiscovered pathological mechanism – possibly vascular, possibly genetic, possibly environmental – that causes both.
Even though these study outcomes are a little dismaying, there is hope that comes from them. For those who wear hearing aids, it is vital that you have your aids tuned and adjusted on a consistent basis. You shouldn’t make you brain work harder than it has to work in order to hear. The less energy used in the mechanics of hearing, the more brain capacity available for comprehension. Also, if the 2 symptoms are linked, early detection of hearing impairment may at some point lead to interventions that could avoid dementia.