In 2013, Johns Hopkins University researcher and epidemiologist Dr. Frank Lin directed a study which was the first to investigate the potential consequence of hearing loss on cognitive function.
Volunteers with hearing loss took recurring cognitive assessments, used to evaluate memory and thinking skills, over the span of six years. Hearing tests were also carried out over the same period.
What the investigators discovered was concerning: those with hearing loss had cognitive abilities that decreased 30 to 40 percent faster than those with normal hearing, even after accounting for other contributing factors like age, high blood pressure, and diabetes.
But that wasn’t everything. Not only did people with hearing loss experience higher rates of cognitive decline—the decline was directly associated to the intensity of the hearing loss. The more extreme the hearing loss, the greater impairment to brain functioning. Moreover, those with hearing loss presented indications of substantial cognitive deterioration 3.2 years earlier than those with average hearing.
The research reveals a deep association between hearing loss and cognitive decline, but the question remains as to how hearing loss can trigger cognitive decline.
Researchers have offered three explanations for the relationship between hearing loss and cognitive decline:
Possibly it’s a collection of all three. What is evident is that, regardless of the cause, the connection between hearing loss and cognitive decline is strong.
The question now becomes, what can we do about it? Researchers estimate that 27 million Americans over age 50, among them two-thirds of men and women aged 70 years and older, are afflicted by some kind of hearing loss. Is there a way those with hearing loss can avoid or counter cognitive decline?
Remember the three ways that hearing loss is considered to trigger accelerated cognitive decline. Now, contemplate how hearing aids could resolve or correct those causes:
Admittedly, this is only theoretical, and the big question is: does wearing hearing aids, in fact, slow or prevent accelerated mental decline, and can we quantify this?
The answer could be found in an upcoming study by Dr. Frank Lin, the head researcher of the initial study. Lin is working on the first clinical trial to examine whether hearing aids can be objectively measured to protect against or alleviate brain decline.
Stay tuned for the results, which we’ll address on our blog once published.