Hearing Impairment and Dementia Linked?

Do you have hearing loss? If so, do you sometimes find that it seems like work just to understand what the people around you are saying? You are not alone. The feeling that listening and understanding is taxing work is common among individuals with hearing loss – even the ones that use hearing aids.

As though that wasn’t bad news enough, it might not be just your ability to hear that is affected, but also cognitive functions. Contemporary research studies have established that there is a solid association between hearing loss and your risk of contracting dementia and Alzheimer’s.

One such study was conducted by the Johns Hopkins School of Medicine on 639 individuals between the ages of 36 and 90 16-year period. The data showed that 58 study volunteers – 9% of the total – had developed dementia and 37 – 6 percent of the total – had developed Alzheimer’s disease. Investigators found that for every ten decibels of hearing loss, the participants’ odds of developing dementia went up by 20 percent; the more significant the degree of hearing loss, the higher their chance of dementia.

In a similar research study, surveying 1,984 participants, investigators found a similar connection between dementia and hearing loss, but they also found that the hearing-impaired experienced noticeable decreases in their cognitive functions. Compared to individuals with normal hearing, those with hearing impairment developed memory loss 40 percent faster. In both studies, a far more dismaying finding was that this association was not lessened by using hearing aids.

Scientists have proposed several hypotheses to explain the association between hearing loss and loss of cognitive capabilities. One explanation is associated with the question at the beginning of this article, and has been given the name cognitive overload. Some researchers suspect that if you are hearing impaired, your brain tires itself just trying to hear that it has a diminished capacity to understand what is being said. The resulting lack of comprehension can cause social isolation, a factor that has been shown in other studies to cause dementia. Another theory is that neither dementia nor hearing loss cause the other, but that they’re both related to an as-yet-undiscovered pathological mechanism – possibly vascular, possibly genetic, possibly environmental – which causes both.

Even though these study outcomes are a little dismaying, there is hope to be found in them. If you wear hearing aids, visit your audiologist regularly to keep them fitted, adjusted, and programmed correctly, so that you are not straining to hear. The less work used in the mechanics of hearing, the more brain capacity available for comprehension. And, if it turns out that loss of hearing is an early indicator of dementia, detecting the hearing loss early might allow for early intervention to postpone the advancement.