Hearing loss is a natural part of aging nobody likes to admit is happening. But happen it does – and ignoring it comes with a cost. It could put you at risk for another feared consequence of aging: dementia, which affects 60 to 80 percent more Black Americans than white Americans.
“The greater your hearing loss, the more likely you are to develop dementia,” Dr. Alexander Chern, an ear, nose and throat doctor at New York-Presbyterian Hospital in New York City says.
By age 70, research shows 2 in 3 U.S. adults have lost some hearing. Yet the vast majority – more than 80% – fail to seek treatment. Age-related hearing loss is the largest modifiable risk factor for dementia, according to a 2020 report from the Lancet Commission on dementia prevention and care. Hearing loss in midlife accounts for an estimated 8.2% of all dementia cases.
But why that is remains unclear.
What is the link between dementia and hearing loss?
Just as there are many causes for dementia, there also are many potential mechanisms linking hearing loss to a decline in brain health, experts say. And as with dementia, it’s possible more than one is operating at the same time, Timothy Griffiths, a professor of cognitive neurology at Newcastle University in Newcastle Upon Tyne, England says.
One possibility is that the same disease process causing hearing to deteriorate is likewise harming cognition, Griffiths, adds. For example, the small strokes that cause vascular dementia could be affecting the inner ear. Another possibility is that hearing loss decreases activity in key regions of the brain responsible for thinking, leading to an increase in neurodegeneration.
“It could be there’s a boosting effect on the brain from being able to hear, which allows you to better process auditory signals and experience speech and communication and emotional communication,” he says. “Impoverished input leads to impoverished brain reserve, so that leads to a higher risk for dementia.”
A third possibility is that hearing loss forces a person to drain other cognitive resources, Griffiths shares. “A large number of studies suggest listening under difficult conditions makes it harder to carry out other tasks that require attention. You have to use a lot more brain effort to listen to things, and that brain effort is taking away from the amount of resource you might devote to other activities.”
Or, it could be that increased activity in the part of the brain responsible for listening under difficult conditions triggers acceleration of the