Comorbidities

Hearing Loss and Cognitive Health

Last update on Mar, 04, 2020

Approximately 5.7 million people in the United States are living with Alzheimer’s disease and other forms of dementia, according to the Alzheimer’s Association. People frequently associate dementia, as well as general cognitive decline, with advancing age. However, the following conversation between two sisters suggests that another risk factor may be in play…

Janelle: “Dad really had me worried last night.”

Kathy: “Why, what happened? Didn’t you take him to the theater?”

Janelle: “Yeah, but we almost didn’t make it. When I went to his house to pick him up, he wasn’t ready. He said he didn’t remember we were going, even though I had called in the afternoon to remind him.”

Kathy: “I’ve noticed that he seems more forgetful lately. Anyway, you made it to the play. Did he enjoy it?”

Janelle: “You know how it goes - he complained about not being able to hear a lot of the lines.”

Heaing loss is a risk factor for cognitive decline

Because their dad is older, perhaps in his 80s, Janelle and Kathy attribute his forgetfulness to his age — which is indeed one of the risk factors for cognitive decline and dementia. But Janelle’s last comment about his inability to hear parts of a theatrical production points to the possibility of a risk factor that’s not widely understood or recognized: hearing loss. These sisters might be surprised to know that hearing loss is a risk factor in an estimated 36% of U.S. dementia cases, according to Johns Hopkins research conducted by Frank R. Lin, MD, PhD, and Marilyn Albert, PhD. In another study, Dr. Lin concluded that mild hearing loss doubled an adult’s dementia risk, moderate hearing loss tripled the dementia risk, and severe hearing loss increased the dementia risk fivefold.

As Dr. Lin noted, hearing loss doesn’t have to be substantial to have an impact on cognitive health. In fact, researchers at New York-Presbyterian/Columbia University Irving Medical Center concluded that a 15-decibel loss — roughly equivalent to the volume of a whisper or rustling leaves — increased an older adult’s risk of “clinically meaningful” cognitive decline.
While cognitive decline doesn’t necessarily equate to dementia, it still needs to be taken seriously. The Alzheimer’s Association contends that even mild cognitive decline increases a person’s risk of developing Alzheimer’s disease or another dementia.

A couple talking with an Amplifon hearing professional in an Amplifon center

A senior woman trying her new hearing aid

The connection between hearing loss and dementia

There’s no clear-cut answer to the question of why hearing loss boosts the risk of cognitive decline and dementia.

Social isolation may play a significant role. People with hearing loss tend to avoid social situations, especially when background noise makes it too difficult to communicate. Social isolation, which can morph into loneliness, is a known risk factor for cognitive decline and dementia. A study by researchers at Rush Alzheimer’s Disease Center found that lonely individuals may be twice as likely to develop the type of dementia linked to Alzheimer’s disease as those who are not lonely.

Experts have suggested other possible mechanisms for the hearing loss-cognitive decline connection. For example, the brain in a person with hearing loss may undergo “cognitive load,” that is, it’s stressed by constantly straining to understand speech and other sounds. This uses up resources that would otherwise be available for other functions such as learning and memory. Yet another possibility: Hearing loss may alter brain structure in a way that contributes to cognitive problems.

Complete the health conversation

The sisters involved in the “overheard” conversation above are justifiably concerned about their dad’s cognitive health. They may wonder whether he’s in the early stages of dementia — a condition that takes a terrible personal toll on the individual as well as loved ones.

Dementia also comes with an enormous economic burden. In 2019, the direct costs to American society of caring for those with Alzheimer’s and other dementias totaled an estimated $290 billion, according to the Alzheimer’s Association. Much of this expense is borne by Medicare, Medicaid and health insurance companies.

At the same time, the conversation between Janelle and Kathy illustrates a widespread unawareness of the connection between hearing loss and cognitive decline, even when a person exhibits obvious signs of both conditions.

Could their dad’s cognitive health benefit from treatment of his hearing loss? No one can say for sure. However, some research suggests a cognitive benefit from hearing loss treatment.

Dr. Justin Golub, who has studied the correlation between hearing loss and cognitive decline, “suspects that people might be able to remain more mentally sharp if they started wearing hearing aids as soon as they started to have even mild issues with hearing,” reports a Reuters Health article.

Another study conducted by the University of Exeter and King’s College London concluded that people who wear hearing aids for age-related hearing loss maintain better brain function over time than their non-aided peers. Exeter’s PROTECT online study involved 25,000 people age 50 and over, divided into two groups: hearing aid wearers and non-wearers. Participants took annual cognitive tests over a span of two years. After that time, those who wore hearing aids performed better in measures assessing working memory and aspects of attention than those who did not.

“We know that we could reduce dementia risk by a third if we all took action from mid-life,” says Exeter Professor Clive Ballard. “This is an early finding and needs more investigation, yet it has exciting potential. The message here is that if you’re advised you need a hearing aid, find one that works for you. At the very least, it will improve your hearing, and it could help keep your brain sharp, too.”

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Talk to an expert

As a health insurer or employer, your organization can help complete the conversation by making hearing aids and hearing health care services more accessible through a hearing benefit or hearing health care program. Contact Amplifon Hearing Health Care for more information.