For people reading this who have suffered some type of hearing impairment, do you ever find yourself having to work really hard to understand what is being said to you or around you? This sense of having to work to understand people is common even among people who wear hearing aids, because they must be adjusted and tuned correctly to work well, and people need to become accustomed to wearing them.

This frequent sensation may affect more than your hearing; it might also influence your cognitive abilities and your memory. In newly released studies, researchers have discovered that hearing loss significantly increases your chances of developing dementia and Alzheimer’s.

A 16-year study of this connection from the Johns Hopkins School of Medicine involved 639 volunteers between the ages of 36 and 90. At the end of the study, scientists found that 58 people (9 percent) had been identified as suffering from dementia, and that 37 of them (5.8%) had developed Alzheimer’s disease. The level of hearing loss was positively correlated with the odds of developing either disorder. For every 10 decibel additional hearing loss, the risk of developing dementia increased 20 percent.

A separate research study of 1,984 people, demonstrated comparable results linking dementia and hearing loss. In this second study, investigators also found degradation of cognitive functions among the hearing-impaired over the course of the data gathering. The hearing-impaired participants developed memory loss and reduced thinking capacity 40% faster than individuals with normal hearing. A pivotal, but depressing, finding in each of the two studies was that the negative cognitive effects were not lessen by using hearing aids. Several hypotheses have been proposed to explain this apparent relationship between hearing loss and loss of cognitive performance. Researchers have coined the term cognitive overload in association with one particular theory. The cognitive overload hypothesis states that the hearing-impaired person expends so much brain power working to hear, that the brain is tired and has a reduced capacity to comprehend and absorb verbal information. The ensuing lack of understanding may cause social isolation, a factor that has been shown in other research studies to cause dementia. A different line of thought, hypothesizes that dementia and hearing are not causally related to each other at all. Instead the theory states that they are both the consequence of a third mechanism. This unknown mechanism 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 useful lessons to be extracted from them.If you use hearing aids, visit your audiologist regularly to keep them fitted, tuned, and programmed correctly, so that you’re not straining to hear. If you do not have to work as hard to hear, you have greater cognitive capacity to understand what is being said, and remember it. Also, if the 2 symptoms are connected, early detection of hearing loss might eventually lead to interventions that could delay dementia.