Older people with hearing loss may be more likely to develop dementia than other people the same age without hearing problems, according to a new study.
Researchers at Trinity College Dublin looked at data from 36 previous studies involving a total of 20,264 people. Those with age-related hearing loss were 2.4 times more likely to have dementia and twice as likely to have cognitive decline. The analysis looked at whether hearing loss triggers dementia, or if they happen at the same time.
What they found is that hearing loss seems may be a precursor to dementia, not just a coincidental part of aging. Scientists have a theory that cognitive decline occurs because of the energy adults with hearing loss have to devote to navigating the world without hearing.
“A possibility is that hearing loss causes cognitive decline through the increased mental energy required to perceive speech, leaving fewer resources available for other cognitive processes, such as memory,” lead study author David Loughrey told Reuters. “Additionally, research suggests that factors such as loss of mental stimulation, depression or loneliness may be associated with a higher risk of dementia.”
While age-related hearing loss doesn’t sound in itself, it can lead to a variety of health problems and makes day-to-day life more difficult. Adults without other methods of communicating find themselves isolated.
“Researchers have a few theories as to how hearing loss could feed into dementia risk. This includes the theory that the brain is diverting important resources from other areas in order to fully understand and process sounds, or that hearing loss can lead to increased social isolation. Further work is needed to find out whether any of these theories are true,” said Clare Walton, research communications manager at Alzheimer’s Society.
Of course, not all hearing loss will lead to dementia.
“It is important to remember that not all cases of hearing loss will be associated with dementia. It is also important to get your hearing checked regularly, especially in mid-life and older age and to follow the advice of your audiologist,” said Walton.