hearing_loss_dementia

Many studies – both in the U.S. and abroad – have been conducted to determine if we can connect the dots between losing hearing and “losing the mind.” While the studies don’t draw exactly the same conclusions or know what exactly the connection is, most researchers do agree that there is a definite link between age-related hearing loss and dementia.

It’s no surprise that the age group most at risk are older adults … those over 60 years old. This age group claims the highest amount of hearing loss … mostly age-related.  Age-related hearing loss, or “presbycusis” is a sensorineural disorder that’s usually caused by gradual changes in the inner ear. It’s believed that the cumulative effects of exposure to the sounds of daily living – traffic, construction, noisy offices, work equipment, and loud music – are the cause. Other experts say the general deterioration of the body is the culprit, one of the many signs of the aging process.

Regardless of the reasons, with skyrocketing increases in dementia and Alzheimer’s sufferers among our seniors, the connection is an important one to pursue to ease the burden and minds of older adults, their loved ones, and others who care for older Americans.

If a hearing disorder were the cause of dementia, Alzheimer’s, or other signs of cognitive impairment, think what that could mean for our aging population. Testing and correcting for hearing loss might result in dramatic changes in the lives of older adults … those who are losing quality of life, productivity, are homebound, and socially isolated. It could keep the elderly in their homes and away from nursing homes or other specialized out-of-home care facilities – or at least keep them home longer.

The Research

Stig Arlinger of the Department of Audiology, University Hospital, Linköping, Sweden reported in a 2003 article in the International Journal of Audiology:

Most of these studies show such a correlation without being able to show whether the hearing loss caused the reduction in cognitive performance or if both the hearing loss and the cognitive decline are parts of a common, general age-related degeneration. A couple of these studies, however, indicate that the uncorrected hearing loss may be the cause of cognitive decline.

A 2011 study in the JAMA (Journal of the American Medical Association) set out to confirm whether Central Auditory Dysfunction (CAD) was a precursor to the onset of Alzheimer Dementia (AD).

CAD or CADP are terms used to cover a variety of disorders that affect the way the brain processes auditory information. It can affect both children and adults. While they have normal functioning of the outer, middle and inner ear, people suffering from CAD can’t process the information they hear like most of us. The result is they have difficulty recognizing and interpreting sounds – especially speech. It’s thought that the problem is due to a dysfunction in the central nervous system.

In the 2011 study, 274 subjects with dementia were followed up for up to 4 years after undergoing a complete hearing assessment. Twenty-one were diagnosed with Alzheimer’s Dementia after a hearing test. The findings suggested that early detection of those at risk for AD would be important to treat and possibly delay the progression of the disease if new treatments were to be discovered. This would mean that the one million adults undergoing hearing aid evaluations each year in the U.S. might be tested for Central Auditory Dysfunction to stop hearing loss in its tracks. Hearing tests could be a form of pre-screening for this auditory dysfunction.

More Important to Brain Health than Previously Thought

In a 2013 AARP article “Hearing Loss Linked to Dementia” Frank Lin, an otologist and epidemiologist at Johns Hopkins University suggested that hearing loss among the elderly “plays a much more important role in brain health than we’ve previously thought.”

Lin believes in treating hearing loss aggressively to stave off cognitive decline and dementia. He says he knows there’s an explanation for the link between hearing and dementia but that neither he nor researchers know exactly how to explain the link. He suggests these possible reasons for hearing loss leading to dementia:

  • Something physiological like high blood pressure (Lin admits this is probably the weakest explanation)
  • Cognitive Load. This means that the constant straining to understand may be stressing the brain.
  • Effects of brain structure contributing to cognitive problems. This means that certain structures of brain cells can shrink when they don’t get enough stimulation.
  • Social isolation. This supports the long-held theory that hearing problems tend to isolate people from others; they struggle to converse with others and socialize in groups and with less social interaction decline cognitively.

Fewer than 15 to 20 percent of those with a clinically significant hearing loss even use hearing aids. So maybe if we could draw more conclusive evidence about the link between hearing loss and dementia more people – particularly older Americans who risk begin among the growing number of dementia and Alzheimer’s afflicted – would be more inclined to get their hearing tested.

The caring and proficient staff at Acuity Hearing Centers can test for hearing loss and fit seniors with hearing aids in a wide range of styles and features.

Maybe if more older adults saw hearing loss as something not to be dismissed nor to be embarrassed to admit, more of us would be enjoying sharp minds and active lives in our golden years.