By Brian Taylor, AuD, Editor-at-Large
Brian Taylor, AuD
The relationship between hearing loss and cognitive ability has received considerable attention in the academic literature and professional publications over the past several years and for good reason. Both conditions are harmful, and because of the rapidly aging population becoming more prevalent and are likely, without improved intervention strategies, to result in higher healthcare costs over the next several decades.
A recent article, published online at JAMA-Otolaryngology, demonstrates how research findings focused on the link between cognitive decline and hearing loss is beginning to trickle into direct clinical applications.
This is a positive development because a simple Google search of hearing aids + dementia will uncover a litany of erroneous and misleading ads and reports associated with hearing aids use in adults at-risk for developing cognitive decline or dementia.
Discussing Hearing Loss and Cognitive Decline in the Clinic
Michael Harris and Karl Doerfer of the Medical College of Wisconsin and Aaron Moberly of Ohio State University authored a short summary of the underlying theories of the relationship between hearing loss and cognitive decline, and offered some guidance, based on their interpretation of this research, on how physicians and other healthcare professionals should discuss it with patients.
The authors suggest that healthcare professionals discuss with patients and their families the link between age related hearing loss and cognitive decline by emphasizing the correlational (not causal) nature of the relationship of the two conditions.
Further, the authors stress that even though hearing loss is one of the most important modifiable risk factors for cognitive decline and dementia, hearing aids should not be considered a treatment option for reducing or eliminating the effects of cognitive decline or dementia because there is not yet ample evidence to support their use for these conditions per se.
A more nuanced interpretation of the research that examines the relationship between hearing loss and cognitive decline is offered by Nick Reed in the June installment of Gus Mueller’s 20Q at AO. Not only does Reed do a fantastic job of summarizing the latest research in this area, along with its clinical consequences (kudos to Nick for a clear explanation of hazard and risk ratios), he also mentions that even though the research on hearing aids use to stave off the effects of cognitive decline is on-going and still not settled, work by Sara Mamo at the University of Massachusetts-Amherst shows a low-cost, low-risk, nonpharmalogical intervention such as the provision of basic hearing care can reduce some of the day-to-day communication burdens associated with persons who have hearing loss and dementia.
The Memory-HEARS program cited by Reed in the 20Q article was pilot study that delivered a 2-hour in-person intervention in an outpatient setting using trained interventionists who provided hearing screening, communication strategies, and delivery and instruction of a simple over-the-counter amplification device.
Mamo’s study can be found here.
*featured image courtesy health.mil
I don’t understand why we have to lie to our patients that hearing loss and cognitive degradation is as a result of aging! That’s the surest way to demoralize and create negative thought patterns.
I have submitted my key research on this phenomenon to Dr. Kujawa at Harvard Medical for peer review.
“Hearing deficiency begins when the loudness requirements are challenged by interference of noise and similar disturbances. The volume of sound inputs at the ear drum, increases, causing excess sound pressure within the cochlea, increased action potentials that create electrical pressures far in excess of whats need to trigger neural responses at the hippocampus. Within a few months, these excesses begin to damage the nerve, and the myelin sheath leading to electrical leaks, that dilute the signal characteristics leading to sensorineural hearing loss and loss of cognitive efficiency.
OLD AGE HAS NOTHING TO DO WITH IT, UNLESS IT IS OF PATHOLOGICAL ORIGIN IN THE BRAIN!
If old age were implicated we would have had steady state SNHL equally among the populations world wide. But that is not so and research done in remote tribal locations suggest that those people have normal hearing well into their 90’s!
Cochlear saturation is the chief cause of SNHL, and demylination is the chief cause of cognitive changes that lead in some cases to dementia symptoms.