Hearing loss treatment and the role it plays in dementia prevention
Posted by Dr. Ben Cox and Dr. Rena Booth on November 18, 2021
A 2017 study, conducted by The Lancet Commission on Dementia Prevention, Intervention and Care, called dementia “the greatest global challenge for health and social care in the 21st century.”
But you don’t need a study to tell you that. Ask friends and loved ones of the estimated 50 million people worldwide who have dementia (there’s a good chance you are one), and they’ll tell you about the worry, stress, sadness and devastation that dementia leaves in its wake.
Formed to provide recommendations for the prevention and management of dementia, the Lancet Commission published their initial report in 2017, then updated it in 2020.
But before we get to their recommendations, let’s take a quick step back.
Hearing loss is a known risk factor for dementia
Previous studies have long linked hearing loss to dementia. In fact, one Johns Hopkins study concluded that people with hearing loss are up to five times more at risk for developing dementia than peers with normal hearing.
Researchers admit the science is still inconclusive on exactly why hearing loss increases dementia risk, but they agree on three probable reasons, all of which are contributing factors to dementia:
1. Hearing loss shifts the cognitive load of the brain — The brain spends too much energy trying to process what it’s hearing, giving it less time to spend on thinking and memory.
2. Hearing loss accelerates brain atrophy — While all brains shrink as we age, in studies, people with impaired hearing had “accelerated rates of brain atrophy.”
3. Hearing loss leads to social isolation and loneliness — Social isolation has been associated with a 50 percent increased risk of dementia.
OK, let’s get back to the Commission’s recommendations.
12 modifiable risk factors account for 40 percent of dementia cases
In their initial report, the Commission wrote that “dementia is by no means an inevitable consequence” of aging. Rather, they suggest certain “potentially reversible risk factors” might increase a person’s risk of developing dementia. In 2017, those “modifiable” risk factors numbered nine. Three more were added in 2020.
In 2020, the Commission noted, “together those 12 modifiable risk factors account for around 40 percent of worldwide dementias” and calculated that that 40 percent “could theoretically be prevented or delayed” if those risk factors could be managed, modified or reversed.
Hearing loss is the largest modifiable risk factor for dementia
Scored on a scale that ranks them by the percentage reduction in new dementia cases if that risk factor was eliminated, hearing loss ranked the highest, meaning it had the biggest impact on dementia cases.
The remaining 11 risk factors included childhood education, smoking, depression, physical inactivity, social isolation, traumatic brain injury, hypertension, air pollution, alcohol consumption, obesity and diabetes
While some of the risk factors are certainly more challenging to manage or modify than others, hearing loss is both manageable and modifiable through treatment.
The Commission recommends modifying hearing loss in midlife
Dementia doesn’t typically show symptoms until around age 65 and over. But the study’s authors note that dementia likely begins between ages 40-65. Managing these risk factors at various stages of life could contribute to prevention or delay of dementia.
The recommendation for hearing loss is to manage it in midlife (between age 40-65), before it has a chance to negatively impact cognitive skills. This is consistent with what others have found and said. Of course, treating it anytime you’re ready is smart.
It’s one more very good reason to treat hearing loss
Having dementia is a real concern for older adults and for the people who love them. The good news is that as research sheds more light on the causes and contributing factors of dementia, the more we learn of things we can do to potentially prevent or delay its onset.
Hearing loss is absolutely something we can manage with the help of an experienced hearing professional. If you have hearing loss, this research gives you another great reason to treat it as soon as you can.
•Dementia prevention, intervention, and care: 2020 report of The Lancet Commission
•Dementia prevention, intervention, and care 2020 The Lancet Commission