I was hiking with my older friend at a local park this spring when I heard the lovely call of a Hermit Thrush. It sounds like two flutes playing at the same time and I was eager to share it with my birding buddy. But alas, somewhere along the way her hearing had been damaged (probably a rock concert in the 70’s) and she couldn’t hear this charming sound. It made me wonder if she was able to hear my charming banter as well.
The National Institutes of Health estimate that some 40–50% of adults over the age of 65 years have a measureable hearing impairment, with this figure rising to 83% of those over the age of 70 years. This makes hearing loss is the third most prevalent chronic medical condition among older adults, after arthritis and hypertension.
Besides the inability to hear sounds in nature and spoken communication, researchers have discovered a number of impacts from hearing loss that may have significant consequences for the aging brain. For starters, older adults with hearing loss are more likely to develop problems thinking and remembering than older adults whose hearing is normal, according to a study by hearing experts at Johns Hopkins. The theory is that “degraded hearing” may force the brain to devote too much of its energy to processing sound, at the expense of memory and thinking.
Another potential consequence of hearing loss, according to these same researchers, is that the hard of hearing are significantly more likely to develop dementia and other cognitive problems. In the study, volunteers with hearing loss had cognitive abilities that declined 30 percent to 40 percent faster than in those whose hearing was normal after repeated cognition tests over a six year period.
Even more alarming, levels of declining brain function were directly related to the amount of hearing loss, with hearing impaired older adults developing a significant loss in their cognitive abilities 3 years sooner than those with normal hearing.
Based on these studies, Johns Hopkins hearing researcher Frank Lin, M.D. reframes the significance of this condition by stating that hearing loss “should not be considered an inconsequential part of aging, because it may come with some serious long-term consequences to healthy brain functioning”.
And physical evidence supports the measurable decline: older adults with hearing loss appear to lose brain mass at a faster rate than individuals with normal hearing according to a study at Brandeis University. In the study, those with poorer hearing had less gray matter in the auditory cortex, a region of the brain that supports speech comprehension.
Other studies from the National Institutes of Aging link hearing loss to increased risk of falls, hospitalizations and overall diminished physical and mental health.
Besides the brain changes, there are the social consequences related to hearing loss. People who can’t hear well tend to become socially isolated, furthering the risk factor for cognitive decline and dementia. And let’s be honest: it can be disappointing to spend time with someone who has hearing loss, as I learned on my birding hike.
Researchers urge people as they move through middle age to get their hearing tested annually. If there is a hearing loss, it is wise to take it seriously and treat it. Dr. Lin estimates that only 15% – 20% of those who need a hearing aid get one.
Don’t ignore hearing loss. Your community needs you to stay connected and your brain will thank you as well.
By Sally Anderson