Hearing loss is a risk factor for cognitive decline, dementia

November 4, 2023

We know dementia tends to occur more among the seniors.  We also know that hearing loss is often present in our seniors.  Hence, this started people thinking if hearing loss and dementia are related.

One of the earlier studies done by Johns Hopkins expert Dr Frank Lin and colleagues found that the higher degree of hearing loss one has, the likelihood of developing dementia increases exponentially.  They found that those with mild hearing loss has 2x risk of developing dementia, those with moderate loss has tripled (3 times) risk.  Among those with severe to profound hearing loss impairment, the risk increases to 5x times.

We now know hearing loss contribute towards higher rate of cognitive processing decline.

Why is this so? Possible reasons / hidden risks of hearing loss  

One theory is that hearing-impaired individuals tend to be less social because of communication difficulties which resulted in reduced auditory stimulation which is not good for the brain. With reduced auditory stimulation, brain atrophy may occur where the brain starts shrinking…

Another theory is that as your brain is not getting clear sounds from your ears, your brain reallocates resources to help you hear better.  This is done at the expense of other cognitive processing functions such as memory, thinking or helping to protect the brain against other pathology that can lead to dementia.

In the above situation, it is not just that hearing loss causes dementia, but hearing loss taxes the brain, negatively impacts other important cognitive functions and leads to earlier exposure dementia from other factors that can lead to dementia.

The big question that researchers have been asking is whether treating hearing loss can slow down cognitive decline or reduces the risk of developing dementia in the long term. The good news is a latest large-scale study  showed that older adults with a higher risk of dementia and who use hearing aids may be able to reduce their risk of cognitive decline by almost 50 percent.

Published in the Lancet Journal in 2023,  this study led by Dr Frank Lin of Johns Hopkins University shows that hearing rehabilitation reduced the rate of cognitive decline in older patients at risk of it by almost 50% (48%) over the 3-year study. This is a strong indication that treating hearing loss with hearing aids helps and may be a safe way to lower the risk of developing dementia among the vulnerable population (Those considered at high risk for dementia were older and had lower cognitive scores, among other factors).

Now that we know improving one’s hearing ability with hearing aids intervention help reduce the rate of cognitive decline, lower dementia risk and improve quality of lives , let’s help our loved ones hear better by encouraging them to check their hearing and seek suitable hearing intervention.