The following is a conversation with Dr. Frank Lin, the foremost expert on hearing and public health from Johns Hopkins University.
He talks about why hearing should be checked regularly, technological advances to help you communicate, the link between hearing treatment and reducing risks of dementia, and at what age everyone’s hearing starts to decline (it’s earlier than you think.)
Dr. Lin, you have said that everyone over the age of 20 has some level of hearing loss, yet the average age for people to treat their hearing is over 70. Why do you think that is?
Everyone’s hearing gradually declines over their entire lifetimes, but our brains are pretty adept at compensating for the declines in hearing that come with getting older. At the same time, accessing interventions to assist hearing (i.e., hearing aids) until recently had some pretty incredible barriers—for example, a $4000+ price tag, multiple trips to a clinician needed, etc.
No surprise, then, that the only people who would be willing and interested to get hearing aids would be people who have more advanced levels of hearing loss and who have time and the means to get these devices.
Fortunately, that’s all beginning to change now with OTC (Over the Counter) hearing aid regulations driving innovation and competition in this space. At the same time, there’s a push now toward re-educating the public that hearing changes gradually for everyone and that incrementally adopting technologies and strategies to augment hearing along this continuum is what’s important.
When we talk about hearing health and protection, there is often a stigma associated with treatment. What can we do to reduce that stigma to get people the help they need?
A big part of reducing stigma is normalizing something with language, discussion, and widespread adoption. There are many examples of how normalizing a shared experience or condition has changed the stigma around something - think of how we regard eyeglasses as ubiquitous and fashionable accessories, or how comfortable we are discussing medical conditions we never would have discussed publicly before. This strategy has also helped us shed outdated social stigmas that just don’t serve us anymore.
Hearing is ready for a rebranding! Changes to our hearing are normal. Hearing is not a binary where someone either has hearing or they have hearing loss.
Everyone’s hearing changes as we get older, starting from much earlier than we probably expect, because parts of the inner ear wear out over time and don’t regenerate. If people of all ages understand their hearing and how it changes over time, they can know when to be proactive about protecting their hearing, and when to use communication strategies or technologies to help them hear better.
Most people get their eyesight checked every year, go to the dentist and have an annual doctor’s visit. Do you think an annual hearing test should be part of health maintenance?
Changes to our hearing happen very gradually over time, so many people may not even be aware of hearing problems if they haven’t had a hearing test.
Checking your hearing every 1-2 years is an easy way to understand these hearing changes and to know when to consider adopting strategies and technologies to augment hearing. People can get their hearing checked by seeing an audiologist, or an even easier way to monitor your hearing is to self-test with a compatible smartphone. The website HearingNumber.org takes people through how to do this. The website is part of the Know Your Hearing Number public health campaign created by the Cochlear Center to introduce an easy way to understand and talk about hearing.
Can you explain the Hearing Number? What is it and why is it important?
Hearing happens on a continuum. It changes naturally overtime, and people experience hearing along a spectrum as it changes. The Johns Hopkins Cochlear Center for Hearing and Public Health, which I direct, launched the Know Your Hearing Number campaign to introduce the Hearing Number as a common metric to understand and talk about our hearing.
The Hearing Number reflects how loud speech typically must be for some one to hear it. It is based on the pure tone average, or PTA4, which is one of many ways that hearing care professionals measure hearing. And the Hearing Number is universal – it’s the same no matter where in the world it’s tested.
The majority of speech sounds fall between 500 and 4000 Hz on the audiogram. The Hearing Number/PTA4 is an average of pure tone, air-conduction hearing thresholds at four specific frequencies (500, 1000,2000, and 4000 Hz). The Hearing Number can range from about 0 to 100 dB and can be directly applied to the broad categories that clinicians and researchers use to define levels of hearing loss.
Consumers can learn their Hearing Number from a hearing care professional, or from the Mimi Hearing Test or SonicCloud apps available for Apple phones and tablets.
A simple metric like the Hearing Number can improve the way consumers understand their own hearing and how it changes over time. It can also help hearing care professionals, companies, and retailers effectively communicate with consumers and connect them with the products and services that can help them augment their hearing.
You recently published a breakthrough study that definitively showed the link between hearing loss and possibility of being diagnosed with dementia. How are these two related?
We’ve known for over a decade that hearing loss is strongly linked with risk of dementia and cognitive decline. But we didn’t know if treating hearing loss could in fact reduce cognitive decline and potentially even lower the risk of dementia. The ACHIEVE study found that treating hearing loss in older adults who had more risk factors for cognitive decline slowed down loss of thinking and memory abilities by 48% over 3 years.
There are three main mechanisms that may explain whyhearing loss may be associated with dementia.
First, with hearing loss, speechand sound are garbled by the time they reach the brain, which requires thebrain to use extra effort for processing and deciphering this speech and sound.The brain then has fewer resources for activities like memory and executivefunction, which can eventually lead to cognitive impairment.
Second, with hearing loss, theparts of the brain that are stimulated by speech and sound are now under stimulated,which can lead to atrophy and changes in brain structure and function.
Third, hearing loss can makecommunicating with others more difficult, which can lead to social isolation,another risk factor for dementia.
If I take a hearing test and find myself with a mild to moderate hearing loss on the Hearing Number scale, what should I do now?
The first step would be to congratulate yourself for making the time to learn this important aspect of your health and to recognize that you are in good company: everyone’s hearing changes throughout our lives. So, your hearing now is different than when you were ten years younger, but your hearing then was different from ten years before that! For most people, our hearing changes so gradually that it can be hard to recognize.
Now that you’ve learned your Hearing Number, what can you do? There are communications strategies and technologies that can help your make the most of your hearing. Usually, the higher your Hearing Number is, the more communication strategies and technologies you may need.
Strategies like getting close or face to face, summarizing and clarifying what you heard when you’re having difficulty hearing someone clearly, and avoiding rooms with background noise and reverberation can help.
Simple changes to the technologies you already use can help your hearing too. Using closed captioning on video platforms means your brain won't have to concentrate so hard to catch the dialogue. Voice-over-IP for phone calls - Skype, GoogleVoice, WhatsApp, and FaceTime – will give you better sound quality. And smartphones often offer customizing audio outputs based on your hearing so it's easier to hear calls and listen to music.
When those strategies aren’t enough there are technologies available, from over-the-counter hearing aids coming to the market, to devices prescribed by an audiologist or hearing aid specialist, to surgical options like cochlear implants, that can all help people at different points on the hearing spectrum hear their best.
You were integral to the FDA’s approval allowing for the sale of hearing aids “over the counter,” meaning people can buy at a retail store or online without a medical prescription for those with mild to moderate hearing loss. This opens accessibility to hearing treatment to a much broader range of people at a much more affordable price point. Can you talk about why you, as a medical professional, advocated for this?
My support for over-the-counter hearing aids is rooted in my work as a public health researcher: while 2/3 of Americans over 60 have hearing loss, less than 20% of adults in the U.S. with hearing loss report hearing aid use. This, despite all that we’ve learned about the effect hearing loss has on the health of adults, including increasing loneliness, fatigue, and its adverse impact on thinking and memory abilities. Recently, in a large, randomized trial that I lead funded by the NIH, we also learned that treating hearing loss reduces loss of thinking and memory abilities by 48% over 3 years in older adults at increased risk of cognitive decline—that’s a huge impact!
A big reason for under treatment of this common and very treatable condition is that the average cost for a pair of prescription hearing aids is $4,700, and before the OTC hearing aid market opened, they could only be obtained through a hearing care provider. Many people put off considering hearing aids because of the outrageous costs and hassle involved.
It goes back to the original FDA regulations for hearing aids, which were written in 1977 and required hearing aid sales to go through a licensed provider because hearing aids back then were only safe and effective if programmed by a licensed provider. That made sense then. But technological advances in the intervening 45+ years allow properly designed hearing aids to be safely and effectively used by adults with hearing loss without the need for a licensed provider.
The new regulatory category for over-the-counter hearing aids will spur innovation and increase the accessibility and affordability of hearing aids for millions of Americans with hearing loss.
What would you tell me or anyone else is the most important thing we can do to maintain our hearing health?
One of the most important things you can do to protect your hearing is to avoid exposure to loud noises. If you can’t move away from loud noises, ear protection (such as earplugs or noise protection earmuffs) can help. There are also ways to reduce noise exposure from headphones, like adjusting the settings of the headphones to automatically keep the volume at a safe level,using over-the-ear headphones rather than in-the-ear earbuds, and limiting theuse of headphones to no more than 60 minutes at a time.
About Frank Lin, MD, PhD
Frank R. Lin, MD, PhD is a Professor and the Director of the Cochlear Center for Hearing and Public Health at Johns Hopkins University. As an otologic surgeon & epidemiologist, Dr. Lin has translated his clinical experiences caring for patients with hearing loss into foundational public health research and federal policy in the U.S. His epidemiological research from 2010-2014 established the association of hearing loss with cognitive decline & dementia, and his research served as the direct basis for the Lancet Commission on Dementia conclusion that hearing loss is the leading modifiable risk factor for dementia. Based on this early research, he initiated the ACHIEVE study in 2014, and the results of this landmark randomized trial that were released in 2023 established that treating hearing loss reduces loss of thinking and memory abilities by 48% among older adults at increased risk for cognitive decline.
In parallel, Dr. Lin has collaborated with the National Academies, White House, and Congress to develop policies to ensure hearing loss can be effectively and sustainably addressed in society. These efforts directly resulted in bipartisan passage of the Over-the-Counter Hearing Aid Act of 2017 which Dr. Lin testified on before Congress and final enactment of federal regulations for OTC hearing aids in the U.S. on October 17, 2022. Dr. Lin has subsequently collaborated with the Consumer Technology Association to develop the standard for a consumer-facing hearing metric based on the PTA4 (Hearing Number) to empower consumers to track, monitor, and act on their own hearing. As the director of a public health research center, Dr. Lin’s academic efforts are focused on reshaping the rules and assumptions underlying the global hearing care market in order to ensure the market is optimized to advance public health.
About the Cochlear Center
The Johns Hopkins Cochlear Center for Hearing and Public Health is the only global research institution focused exclusively on issues related to hearing loss and public health in older adults. Founded in 2018 and based in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health, Cochlear Center researchers are interested in understanding the impact of hearing loss on public health. We focus on what can be done now across five core areas - population health evidence, public awareness, policy & legislation, technology, and healthcare delivery - to address hearing loss in older adults at scale.
