5 Ways Hearing Loss Raises the Risk of Dementia
Researchers from Newcastle University in the UK recently shared a startling statistic: Epidemiological studies show that untreated hearing loss is responsible for 10% of all cases of dementia.
For some time, scientists have studied this connection. Research shows that certain underlying causes can cause both dementia and hearing loss. But in many cases, hearing loss directly raises the risk of dementia. To better understand the cause and effect aspects of this connection, here are five avenues neurologists are exploring:
Hearing loss increases abnormal proteins in the brain. The University of Newcastle team, headed by Prof. Tim Griffiths, found that an area of the brain associated with long-term memory is also important for processing sounds—and that this part of the brain is where Alzheimer’s typically begins. “Changes in brain activity due to hearing loss might directly promote the presence of abnormal proteins that cause Alzheimer’s disease, therefore triggering the disease,” the team noted.
Hearing loss accelerates age-related shrinkage of the brain. While it’s normal for the brain to become smaller as we grow older, Dr. Frank Lin of the Johns Hopkins School of Medicine said, “The shrinkage seems to be faster-tracked in older adults with hearing loss.” Lin and his team used MRI imaging to observe these changes. In another MRI study, a research team headed by Brandeis University neuroscientist Dr. Arthur Wingfield found that people with poor hearing had less gray matter in the area of the brain that processes speech. Said Dr. Wingfield, “The sharpness of an individual’s hearing has cascading consequences for various aspects of cognitive function. We’re only just beginning to understand how far-reaching these consequences are.”
Hearing problems add to the brain’s “cognitive load.” Moving through life is much more difficult when a person is struggling to understand speech and other sounds. Dr. Lin’s team noted, “The strain of decoding sounds over the years may overwhelm the brains of people with hearing loss, leaving them more vulnerable to dementia.” And according to Dr. Wingfield, “Even if you have just a mild hearing loss that is not being treated, cognitive load increases significantly. You have to put in so much effort just to perceive and understand what is being said that you divert resources away from storing what you have heard into your memory.”
Hearing loss lessens access to mental stimulation. When it comes to brain health, “use it or lose it” is true, say experts. Without things to keep it busy, the brain can atrophy. Seniors with hearing loss miss out on many sources of sound-related brain exercise, such as conversation, cultural events, radio and TV programming and music. This can lead to depression, which is also harmful for brain health.
Hearing problems raise the risk of social isolation. Experts say loneliness is as dangerous to our brain health as smoking or obesity. As it becomes harder and harder to hear and to understand what people are saying, seniors may gradually withdraw from interaction with others. This can be another factor in depression, and makes it less likely that an older adult will exercise, eat well, and follow other brain-healthy practices.
Fortunately, hearing loss is one risk factor for dementia that we often can do something about.
The above findings should motivate people of every age to protect their hearing! Avoid loud noises, or wear ear protection. Don’t crank up the volume of personal listening devices. Have regular hearing tests, and report problems right away. (Studies show family and friends may notice a hearing problem before a senior is aware of it, and their observations shouldn’t be discounted.)
Hearing aids help many seniors improve their hearing. Family can help loved ones overcome obstacles to obtaining and using these devices. Financial help may be available to cover the cost. Getting used to hearing aids and making repeat trips to the audiologist for adjustment can be challenging; family and senior living community staff can encourage a senior to stick with it.
The sooner hearing loss is diagnosed, the better. If a senior puts off getting a hearing aid as hearing declines, the brain can actually lose the ability to process and understand sounds. Said Dr. Lin, “If you want to address hearing loss well, you want to do it sooner rather than later. If hearing loss is potentially contributing to these differences we’re seeing on MRI, you want to treat it before these brain structural changes take place.”
And finally, it’s important to note that even if an older adult already has Alzheimer’s disease or other dementia, treating their hearing loss can slow the progression of the disease and make it easier for them to communicate and remain alert. It’s important to work with a hearing specialist who is familiar with the special needs of people with dementia.
The information in this article is not meant to replace the advice of your health care provider. Talk to your doctor or audiologist about your hearing health.