Hear, hear for preventing cognitive decline

Addressing hearing loss doesn't just help improve quality of life in older adults but has also been linked to a lower likelihood of cognitive decline and dementia in recent studies.

Nearly 20% of U.S. adults ages 40 to 69 years, as well as 43% of those ages 70 years and older, report some hearing loss, according to data from the National Health Interview Survey published in 2015. More recent data have found clinically measured prevalence as high as 67% in older adults. Primary care physicians are left with scant guidance on what to do about that, since the U.S. Preventive Services Task Force concluded in 2021 that there was insufficient evidence on screening's benefits and harms to make any recommendations.

Older adults themselves may be averse to acknowledging hearing loss, or it may have occurred so slowly that they aren't aware of it, said Carrie Nieman, MD, MPH, an associate professor of otolaryngology-head and neck surgery at Johns Hopkins University School of Medicine in Baltimore. “We know when people self-rate their hearing that it's not always reflective necessarily of their degree of hearing loss,” she said.

That's particularly problematic since recent research has identified an association between hearing loss and reduced cognition or dementia, said Justin S. Golub, MD, MS, an associate professor of otolaryngology-head and neck surgery at Columbia University Irving Medical Center in New York City. Those findings, plus the FDA's move in late 2022 to authorize the sale of over-the-counter (OTC) hearing aids, has focused overdue attention on hearing loss, he said.

“Almost everyone over 60 is guaranteed to get hearing loss, and it's rarely treated,” said Dr. Golub. “That is surprising. There are few other conditions in medicine that are so common and so rarely get treated. And now we finally have evidence that it's probably important to treat.”

Dr. Golub was the corresponding author on an editorial accompanying a study on this topic. The systematic review and meta-analysis, published Dec. 5, 2022, by JAMA Neurology, found that wearing a hearing aid was associated with a 19% lower risk of long-term cognitive decline versus not correcting hearing loss. Researchers also found that adults who used a hearing aid or a cochlear implant exhibited a 3% short-term improvement in cognitive test scores compared with those who did not.

Additional evidence was provided by a recent study of over 2,400 adults ages 65 years and older. The overall prevalence of dementia was 10.3%, and the rate increased with the severity of hearing loss, according to findings published Jan. 10 in JAMA. Among the 853 participants with moderate to severe hearing loss, dementia prevalence was 61% higher than in those with normal hearing.

The study incorporated a representative sample of older adults, as it was based on data from the National Health and Aging Trends Study, which conducts home-based visits and oversamples from underrepresented groups and adults ages 90 years and older, said audiologist Nicholas Reed, AuD, senior author and an assistant professor of epidemiology and audiology at Johns Hopkins University in Baltimore.

“This potentially is a more accurate snapshot of the prevalence of dementia among people with hearing loss,” he said, noting that prior research tended to be weighted toward less diverse participants, as well as those with higher incomes and more formal education.

In the clinic, physicians should not lose sight of the role hearing may play in the results of verbally administered screening tests in older adults, said Ardeshir Hashmi, MD, FACP, chief of geriatrics at the Cleveland Clinic in Ohio.

“You have got to be able to hear the instructions of the test and the questions,” he said. “So, if I'm not answering or I'm answering incorrectly, is it because my memory is really affected, or is it because I just couldn't hear you?” Ideally, hearing should be tested before any cognitive or other screening is conducted and any loss addressed before it's administered, he said.

Diagnosing loss

The Task Force's decision not to recommend screening for age-related hearing loss “to some degree infuriated people in my field,” Dr. Golub said, noting that ongoing research is assessing the effects of screening for and treating hearing loss.

“I suspect some of these randomized controlled trials will prove a beneficial effect of hearing aids,” he said. “Just like it's super obvious that if you walk around with glasses, you'll do better in life versus walking around with blurry vision.”

Primary care physicians should ask patients about any hearing changes once they reach age 60 years, Dr. Golub said. Check even sooner, ideally starting in their 50s, if they've worked in a factory or other noisy setting before hearing protection became more common, he said. Certain medications also can boost risk, such as cisplatin-based chemotherapies or some antibiotics, such as gentamicin, he added.

Patients' feedback may not always be clear-cut, as those with mild to moderate hearing loss might describe any changes indirectly, said Dr. Nieman, who also coauthored a related “In the Clinic” published in Annals of Internal Medicine on Dec. 1, 2020. “They're going to be saying things like ‘People are mumbling. It's not me. It's them,’ or ‘I feel like I can hear just fine, that's not the problem. But I can't always understand.’”

Dr. Hashmi suggests framing questions in the broader context of quality-of-life frustrations. “I always start off by saying, ‘We're in a nice quiet room right now,’” he said, before asking patients if they can hear him clearly. “Then I say, ‘Well, what happens when you go into a noisier environment like a restaurant or a mall where there's a lot of background noise? Is it still that easy?’ Then people will usually open up, saying, ‘No, that's a different sort of thing.’”

Before referring a patient to an audiologist, a physician can conduct a more formal assessment with a 10-item questionnaire called the Hearing Handicap Inventory for the Elderly Screening, Dr. Hashmi said.

He also has been working with Cleveland Clinic colleagues in audiology, geriatrics, and primary care to assess another approach, in which patients complete a roughly two-minute screening using a computer tablet with headphones on, no soundproof area or booth required.

Early results from his research, which has involved nearly 1,300 patients ages 50 years and older, indicate that up to two-thirds of hearing loss that would have been otherwise missed is being identified by the tablet-based screening approach, Dr. Hashmi said.

Medicare and most other insurance plans cover an audiology assessment, Dr. Nieman said. But not all patients may be interested, and it may not even be a realistic goal to refer all patients.

Instead, physicians could suggest that patients try a phone-based screening self- assessment, such as the Mimi or SonicCloud hearing tests, Dr. Nieman said. With headphones, users can test themselves and gain broad insight into any difficulties. The technology essentially provides a quick hearing snapshot, she said, “if they just want to put their toe in the water and see where they're at.”

Physicians should also consider hearing difficulties when treating affected patients for other conditions. Keeping exam rooms quiet and well-lit is a good start, Dr. Reed said. Along with ensuring they have the patient's attention, physicians can rephrase key points to provide broader context in case some words have been missed, he said. Speak slower and at a lower pitch, he suggested, and avoid shouting.

“Yelling tends to distort things further,” he said. “Hearing loss is a clarity issue—it's not a volume issue.”

Speech-to-text transcribing technology can notably improve physician-patient communication, Dr. Reed said. Amplification devices such as pocket talkers should be kept handy but shouldn't be overly relied upon. “I actually find that physicians in particular, when they use the pocket talker, they actually become worse communicators because they think they've cured the hearing loss,” he said.

Hearing device guidance

When hearing loss seems likely, an audiologist referral can yield not only a diagnostic assessment but patient education on the various hearing assistive devices available, including but not limited to OTC or prescription hearing aids, said Victoria Sanchez, AuD, PhD, an audiologist and an assistant professor in the department of otolaryngology-head and neck surgery at the University of South Florida in Tampa.

“I would love physicians to encourage their patients to acknowledge that hearing health is important, and that there's likely something out there for any budget that can potentially provide benefit,” she said.

For instance, patients should know about home-based devices to alert them to crucial sounds, whether that's a smoke alarm, the doorbell, or a baby crying, Dr. Sanchez said. They can be taught to set up the captioning option on their television screen and that movie theaters must provide hearing assistive devices upon request, she said.

Before patients purchase an OTC hearing aid, an audiologist can guide them on which elements to consider, depending on their communication difficulties, Dr. Sanchez said. For example, a patient with trouble hearing on a cellphone can be advised to look for an OTC device with Bluetooth connectivity.

If patients exhibit severe loss, they can be referred for a consultation about cochlear implants, Dr. Golub said. “The life-changing benefits of adult cochlear implants are not well recognized by the broader medical community,” he said, adding that an April 16, 2020, article in the New England Journal of Medicine provides a good overview.

The outpatient procedure typically requires under two hours, Dr. Golub said, and older age shouldn't disqualify someone as long as they get medical clearance. “We even implant people in their 80s or 90s if they are medically fit.”

Most aging adults, though, will have more subtle age-related hearing loss, with nearly two-thirds in the National Health Interview Survey reporting that they have “a little trouble hearing.” OTC hearing aids are designed for mild to moderate hearing loss, and the marketplace is still in its early stages and rapidly evolving, Dr. Nieman said. She is on the board of the nonprofit Hearing Loss Association of America, which has developed a guidance sheet on which patients might be good candidates for these devices and what questions they should ask before purchasing one. This and other consumer resources are online.

Patients also can consult with an audiologist after purchasing an OTC hearing aid to gain optimal benefit, Dr. Sanchez said. While patients likely would have to pay a few hundred dollars out of pocket, it could pay off significantly if they don't find the device easy to use from the start.

“If you invest $500 [on an OTC hearing aid], which is still a good chunk of money, you'd want to make the most of that investment,” she said. “It would be a shame to buy something, and you feel overwhelmed, you don't know how to use it, and it ends up in the drawer.”