The Importance of Knowing and Optimizing Your Hearing Health…At Any Age

The following is a transcript of Public Health On Call’s episode, The Importance of Knowing and Optimizing Your Hearing Health…At ANY Age.

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[Show Intro, Joshua Sharfstein: Welcome to Public Health On Call, a podcast from the Johns Hopkins Bloomberg School of Public Health, where we bring evidence, experience, and perspective to make sense of today’s leading health challenges. If you have questions or ideas for us, please send an email to PublicHealthQuestion@jhu.edu. That’s PublicHealthQuestion@jhu.edu for future podcast episodes.]

Lindsay Smith Rogers: This is Lindsay Smith Rogers. As we get older, our hearing declines and can impact many dimensions of our health. In today's episode, Dr. Frank Lin, director of the Cochlear Center for Hearing and Public Health, talks about your Hearing Number, a measurement of the softest speech a person can hear, and how a new app can help you figure this out. We also discuss what you can do once you know your Hearing Number, and why there's still so much stigma around hearing loss. Let's listen.

Dr. Frank Lin, thank you so much for being here on Public Health On Call.

Frank Lin: Thanks for having me, Lindsay.

Lindsay Smith Rogers: So today we're gonna talk about hearing loss. So where do we start?

Frank Lin: So hearing—or the flip side of hearing loss—I think is something we all take for granted. It's one of the five senses that our brain depends on. And the amazing thing about hearing is, as much as we rely on it for everything we do—for communicating, talking, hearing a car coming down the road—it's something that declines for everybody as we get older. And that's because, interestingly, compared to other senses in the body, other systems in the body, the inner ear—called the cochlea—it can't regenerate.

So everybody, no matter what you do, no matter who you are, no matter what you even try to do in terms of hearing protection, everybody's hearing will slowly, bit by bit, decline over your lifetime. So I think in the past, it's always been sort of taken for granted. It's like, oh, it’s just Grandma or my mom having hearing loss, and it doesn't really matter. But I think, increasingly over the last 10-15 years, it's borne out, that's actually not quite true. Because it's so fundamental to the brain, we're understanding that as hearing declines for all of us, to some degree, it actually impacts our health.

Lindsay Smith Rogers: And how does it impact our health?

Frank Lin: So I think the big thing is, if you look at the data, so I think, empirically. The other hat I wear besides being a public health scientist, I'm actually an ENT surgeon. So I see patients who have hearing problems coming in for issues. And it's something, I think, you talk to any clinician, they're like, oh yeah. It affects social function, it affects how people think. They get tired, their kids complain, they're not like their usual selves. They don't seem to be as quick as they used to be.

But that was never really borne out by evidence, because no one had ever really done, literally, the research just asking, purely from an epidemiologic perspective, really basic: Hearing or hearing loss is your exposure, and you look at outcomes like cognitive and brain function, brain aging, brain structural changes, falls. It's a very basic question, but no one really asked those questions until about a decade ago, because I think it was always like, again, just "oh, it's hearing loss, it doesn't really matter." It's just like getting some white hair.

So we actually began that research about 10-15 years ago with many other groups around the world. Just people began sort of crossing silos, people who think about hearing didn't think about the other stuff about aging and health. People studying about aging and health didn't think much about hearing. But if you actually look at that data, you see that hearing loss, or hearing, is arguably the single largest risk factor for dementia at the population level, because of just how common hearing loss is and how strong a relationship is. But you also see a relation between hearing and falls, between risk of social isolation and loneliness. All these things that I think for all of us, as any of us just get older, we care about.

And increasingly, I think it's— The important thing about that too, it's not just— There's always notions of correlation or causation, right? And correlation wouldn't be very interesting. It's just like saying, like, white hair is linked with dementia. Sure, it is, but it doesn't really matter. Increasingly we're understanding that it's not just correlation. And actually it is causation for how hearing affects the brain, in terms of how much harder the brain has to work, and/or it leads to faster rates of brain atrophy, and/or through just the loss of sort of social connectedness that's incredibly important for maintaining our health as we go older.

Lindsay Smith Rogers: So what do you do about it?

Frank Lin: So I think in the past, it was always, like, we had this wonderful evidence that hearing was important. And then recently, actually, after almost a decade of work, with funding from the National Institute on Aging, we actually had a trial, a randomized trial, that tested: If you treat hearing loss in older adults, do you, in fact, make a difference? Do you, for example, reduce things like cognitive decline? Lo and behold, after many, many years of funding, after a thousand-person randomized trial carried out through the United States, we actually know the answer to that now.

Namely, for older adults at risk of cognitive decline, if you actually address and you treat your hearing it actually reduces the rate of loss of thinking and memory abilities by almost 50%, so it's not insignificant. So there's wonderful evidence, that's great. But a big issue in the past then was, I think all of us probably know, hearing aids are really expensive. The average cost in the States used to be about $4,000, which amazingly, that means for the average American, it could be your third largest material purchase in life after house and a car, which is just absurd. We have changed that.

So over a period of many years, working with the National Academies of Medicine, working with Congress, working with the White House, we got a law passed seven years ago now, that reregulated hearing aids. That went into effect just two years ago. So hearing aids, for the first time ever now—and the U.S. is the first country in the world to have a regulated market of over-the-counter hearing aids—it's driving innovation, and I would say accessibility at scale. Case in point: Apple. Right? Apple, one of the most valuable companies in the world, they have just announced as of two months ago, and it went into effect just a month ago, AirPod Pros can do your hearing test and they can serve as hearing aids. And AirPod Pros, I think, are $200. So it's increasingly driving innovation with the right type of regulations. So that's great.

So now we have wonderful evidence that hearing matters, that treating can make a big difference as all of us get older. We have the most wonderful policy in the United States that can drive innovation, with companies like Apple entering the market. But the third big missing piece, though, is: If no one actually knows their hearing, it doesn't really matter. And the example I give here all the time is, I would say, if we ask most people out there—and I won't ask you, Lindsay—but like, the last time most got their hearing tested was probably when they were seven years old in primary school. So we have all this evidence that hearing matters, that hearing is important. We have all these wonderful technologies coming from companies like Apple, but no one knows their hearing—what gives?

So the third major thing we're working on is the whole, fundamental issue of awareness, which is just completely germane to all public health. You have to have awareness of the issue before people can do [something] about it. And the way we're going about that is, actually, we actually created an app called the Hearing Number app. It's completely free, it's made by the Johns Hopkins Bloomberg School of Public Health, and it actually tells consumers—if you take this, you download this app, it takes about five minutes to do the test—you actually learn your Hearing Number.

And all the Hearing Number is, is a fancy way of saying it's the softest speech sound you can hear. So kids can have numbers as low as negative ten decibels, super soft. That number will increase as we get older. But in the past, people never really had a number to tie to their hearing. It's just like, you were told, "Oh, you have good hearing" or "you have hearing loss." But we don't say the same things for, let's say, like weight or blood pressure or your cholesterol. Your cholesterol is good or bad, or it's, you know— people have numbers to attribute it to. We never had that for hearing, at least from the public sense; we always had that clinically, but we never really gave out the number, I don't know why. But increasingly now, consumers can get the number themselves. I think it becomes incredibly powerful if you think about hearing as being this metric of your lifetime that you follow of your life course, much like any other metric of your health or wellness that you may follow already.

Lindsay Smith Rogers: So I'm gonna cut through the noise a little bit here and say that I cheated ahead of our conversation, and I did use the app and find out my Hearing Number! Which I won't necessarily share that number here... 

Frank Lin: Aw [laughs]

Lindsay Smith Rogers: I think it was like 13. So what does that mean for me?

Frank Lin: Yeah, so we are in the same boat. My Hearing Number is a 10 in my left ear, 12 in my right ear, which, if we use the classic definitions of, quote, unquote "hearing loss" the World Health Organization established years ago… Technically, by the WHO... I shouldn't say "technically;" this is what it is. If your Hearing Numbers—that's the softest sound you can hear—is better than 20 decibels, that's considered, quote, unquote "normal hearing." Between 20 and 34, it's mild hearing loss. 35 the 50 is moderate hearing loss, et cetera, et cetera, right?

So both you and I, Lindsay, we fall in the normal hearing category. You know, good for us. But the amazing thing about that, the reason why the number is so powerful, is that if you had asked me a few years ago, "Frank, how's your hearing?"—I've been studying my hearing my whole life—I'd be like, "Oh, my hearing's great," right? And actually, literally, the first time—it's crazy for me to say this—the first time I ever got my hearing measured was three years ago when I did this app on my phone that was available at the time through the iOS—it's called Mimi, you can actually get your Hearing Number that way—and that's literally the first time I ever had a hearing test done in my entire life, despite the fact that I am a board certified otologic surgeon, sort of known for my work on hearing and treating hearing loss. This is crazy when I say that, but that was the first time I ever had my hearing tested.

But anyway, the case in point: When I got that Hearing Number, I was like, "Oh, my hearing is great." It's also called the 4-frequency pure tone average, it's between around 10 and 12. I was like, very proud of myself. And on a lark, a few months later, I'm like, "Audrey,"—Audrey, my daughter, was 16 years old at the time—I'm like, "Audrey, you know, you might just, you know, do it yourself." And when she got her results back, her results were a negative five. [laughs]

Lindsay Smith Rogers: That's a big difference.

Frank Lin: When I saw that, I was like, I guess I really am 30 years older than you. Right? Because, when I use her as a proxy myself, which is probably not unfair, my hearing has shifted from -5 back then to 10, where it roughly is now. And if I think about it enough actually, I know for a fact if I'm in a busy restaurant with my daughter, she hears better than I do. I'm struggling just a bit more. I lean in a bit more, and it's because my hearing has shifted 15 decibels in 30 years, which is completely appropriate. But if you ever thought about clinically classifying my hearing, I would be considered normal, and hence I don't need to do anything. And then all of a sudden, one day, I would cross over this magical threshold of 20 decibels and all of a sudden I'd be told I have mild hearing loss. It just doesn't make sense how we treat it: fundamentally a quantitative concept, qualitatively with such arbitrary categories.

So with a Hearing Number of 10, I mean, for me... I'll tell you, in general, when you say Hearing Numbers between roughly 10 and about 50 to 60, that's in the range where you could even consider OTC hearing aids. And what I mean by that, like, it's crazy for me to say this: Ever since Apple released their hearing aid feature, I actually turned mine on in my AirPod Pros, and there's something called Conversation Boost, basically just a directional microphone. It basically tunes into whoever's in front of you. And I've actually started using it. So if I'm in a busy enough restaurant, like a really loud cocktail party type of restaurant, I literally put these AirPods in, and whoever I'm looking at, it makes it easier for me to hear, right? And I don't use them elsewhere for that purpose, it's just only in those situations.

But it's amazing for me, when you make these technologies accessible, all of a sudden, you know, I'm 48 years old. Am I a hearing aid user? I guess technically I am, right? So all of a sudden, it makes these technologies to actually just augment your life, augment your hearing, to hear better, which is what I think anyone wants to do. It's not all of a sudden this cliff you have to jump off of when you're, like, 70 years old, and now you have to finally admit that you're a hearing aid user.

It's one of those things that, as people think about their hearing as just a continuum over a lifetime, these technologies are accessible, they're in your pocket already. It changes the dynamics of how you think about optimizing your hearing across your lifetime. And I think the important thing about the idea of optimizing hearing is you're fundamentally talking about optimizing your health, given that hearing subserves everything we do on a daily basis.

Lindsay Smith Rogers: I was gonna ask you, if doing what sounds like a little bit of an intervention early on: Does that actually help preserve some of your hearing or preserve some of that cognitive function?

Frank Lin: So, the scientific answer to that is, we don't know. That requires long-term epidemiologic studies, clinical trials, et cetera, et cetera. And listen, while I love science, it can also slightly be just trumped by just common sense, right? I don't know a single condition involving health that it's not better to address earlier. It just doesn't really exist. And especially—it's one thing if the, quote, unquote, "intervention" is risky and it costs a lot of money, or it's just dangerous, that's another question.

But I think when we're talking about using, for example, for me, using my AirPod Pros, there's no risk with that. There's not as much financial risk—I own them anyway—so how could it not be beneficial in a way? So I think there's a common sense element in terms of thinking about what the intervention is in terms of risk-benefit calculus.

You know, pop back to the other thing you mentioned too, though, which is about, how do we use this number? I'll tell you one really interesting thing is: I told you my daughter, her Hearing Number is a -5, and then she has a really close friend in college—she's in college now, she's 18 now—and his Hearing Number, even though they're the same age, his is an 18. And he's like, "wait, why is my hearing, like, worse than your dad's?" And she tells me, he's much more conscious about it now, when he's, like, in a bar, he's like, "man, is it too loud here? Should I be using some hearing protection?"

So I think it's an element that, I think for him, he would never have thought about his hearing. If he took any hearing test, he'd be like, "oh, I have normal hearing, I'm good to go.” But when you think about it conceptually, he's like, "my hearing is literally worse than your 40-year-old dad's." And that's a normal hearing—18 is considered normal—and it's, like, way worse than my daughter's. It raises [an] element of awareness that's never there if you use a qualitative term, right, with that number. So I think even at, like, my daughter's age—at that level, she's not really worried about her hearing—you can think about your hearing just in terms of protecting your hearing.

The whole thing of public health is: Prevention is number one. If you can do that before you have to treat it. And the thing with hearing, the main preventive thing to really do for hearing is really just noise. Noise is a cumulative over time. It's a cumulative damage to your hearing over time. It's not one event necessarily. It's just a cumulative of your lifetime. And the tricky thing about that is that every person has individual susceptibility to noise. So one person's noise doesn't affect their hearing as much as another person's, and there are a lot of genetic and other risk factors that link that—we don't even know sometimes. But this idea, then, if you track your own hearing like any of the metric—like you track your own blood pressure, track your own weight—you can take the individual steps you need to do to protect and prevent something from occurring.

Lindsay Smith Rogers: So you mentioned, we've got new evidence, okay, we've got new technology and innovation. We now have an accessibility feature, like, this is something anybody can use on their smartphone at any time. But there's one thing that you haven't mentioned.

Frank Lin: Uh oh.

Lindsay Smith Rogers: And it kind of came to my mind when you were talking about your daughter and her friend being 18. Everybody might have a different Hearing Number, much like everybody might have different ability in sight. But yet we do, early on, these interventions with glasses and contacts. But the idea of, let's say your sight's really bad and you need glasses at an early age, like seven. Nobody thinks about if your hearing's really bad, you might need a hearing aid at age 25 or something. There's a stigma factor here.

Frank Lin: Oh there is.

Lindsay Smith Rogers: Can you talk a little bit about that?

Frank Lin: Yeah, so stigma is a big one. And stigma is not one thing. It's, I think, tied with a lot of things. So one element is clearly, change in hearing gets worse as you get older. So definitely it's clear ageist bias to it, like, to admit you have a hearing loss is to admit you're old. To use a hearing aid is to definitely admit you're old. So there is that element of just fundamental ageism that underlies it. That's one thing.

A second thing, I'll say is a big one too, though, is that, and this is really true, when you put on a pair of glasses, and assuming your vision—most visual loss are just refractive, just the light rays can't bend properly, you put on a pair of glasses, it refracts the light properly, and you see perfectly again, right? So glasses are, in a way, completely, not curative, but, you know what I mean, they completely correct the issue. Hearing isn't like that.

So when you put on a pair of hearing aids… I can assure you, if hearing aids completely restored your hearing perfectly again, back to like when you're a 10-year-old, everyone would wear them, right? Hearing aids aren't like that, though. It's the equivalent of, let's say, the visual equivalent would be macular degeneration. There's been neural damage done to the back of the eye, per se; nothing fixes that perfectly. Hearing is the same way. There's actually been cumulative damage to the inner ear, so the sounds can't be sent properly to the brain.

The main thing any type of hearing technology does: It makes a sound come in clearer so you're able to better accommodate for it, but it's not fixing it perfectly. So I think that's one thing too, is that the actual interventions themselves aren't perfect. Another element too, the sort of stigma angle too, is, I think for a while, just hearing was considered not important necessarily. It's just getting older, just getting some white hair, it's no big deal. But I think that fortunately is being turned over very, very quickly.

The other aspect of the stigma, and one thing that's changing a lot too, is—really, because of how we able to change regulations many years ago, with working with Congress and the White House—with these over-the-counter hearing aids, when a company like Apple enters the field, they set precedents, they set trends. For example, case in point: "Is that someone walking around with AirPods in their ear because they're just walking around with AirPods in their ear, or is it because they're using the hearing aid?" It's one and the same. So it's really allowing, and I think this is really important, this convergence between what is a consumer technology, a hearable, wearable ear bud, versus a hearing aid; it's increasingly one and the same. And that makes it really, really cool, because that clearly, you can imagine, reduces stigma to a great degree.

Lindsay Smith Rogers: So we only have a couple of minutes left, but I want to ask you, first of all, where can people find this app? How do they use it? And then what do they do once they know their hearing number?

Frank Lin: The Hearing Number app is available on Android or iOS. Right now for Android, though, I think it's only available for Samsung and Google phones, but that will change very quickly in the future, and it's available for all iOS phones. You basically just go to Android Play Store, the Apple App Store, you search for the term "hearing number," and it should come right up. It's a completely free app. We don't collect any data. We're not monetizing at all, it's obviously from the School of Public Health. It's completely private, we don't collect any data.

It takes about five minutes. You need to use a pair of headphones. You need to be in a reasonably quiet room, for example, just like in the bedroom of your house, for instance, or just somewhere relatively quiet, is gonna be fine. And then you'll hear different tones, and in the end, will result out your Hearing Number, which can be, again, if you're like my daughter, as low as negative five or ten, all the way up to even 60, 70, 80, potentially, if you have quite a severe hearing loss. With that number then, the app takes you through what you may be experiencing in noise, it includes how to protect your hearing.

In general, the rule of thumb for protecting your hearing is either move away from the sound or turn it down if you can, or use a type of hearing protection. And from there, then, with your Hearing Number, it can guide you to certain technologies. And the general rule of thumb is quite simple. If you're between Hearing Numbers 10 and 60, already you can consider using some type of OTC hearing aid devices. It might be, for example, like me, I use it incidentally when I'm at a really loud cocktail party or bar. But as your Hearing Number goes up, you might need to use them more regularly.

If you're a Hearing Number between 20 and 90, that's in the range where you can go to prescription hearing aids. There's a lot of crossover depending on what you want—a crossover between OTC hearing and, prescription—10 to 60 for OTC, prescription is 20-90.

And then if your Hearing Numbers are above 60, which is quite severe, which is only about 1% of population, you're actually in the range where you can consider things like cochlear implants, which is basically, it's a neuroprosthetic device for people who are still struggling with hearing, despite even using a hearing aid.

So the number clues you in directly into the technologies that you can do throughout your life, beginning even my age, 48, to just help optimize your hearing across essentially your lifetime. So it's not all of a sudden a big deal to all of a sudden admit you need a hearing aid when you're seventy years old; you've been using something like that already for decades, possibly at that point.

Lindsay Smith Rogers: Well, this has been a great conversation, and this is really important information. Thank you so much for being on Public Health On Call.

Frank Lin: Oh, thanks for having me, Lindsay.

[Podcast Credits, Joshua Sharfstein: Public Health On Call is a podcast from the Johns Hopkins Bloomberg School of Public Health, produced by Joshua Sharfstein, Lindsay Smith Rogers, Stephanie Desmon, and Grace Fernandez Cecere. Audio production by JB Arbogast, Holly Cardinell, Spencer Greer, Matthew Martin, and Phillip Porter, with support from Chip Hickey. Distribution by Nick Moran. Production management by Catherine Ricardo. Social media run by Grace Fernandez Cecere. Analytics by Aliza Rosen. If you have questions or ideas for us, please send us an email to PublicHealthQuestion@jhu.edu. That's PublicHealthQuestion@jhu.edu for future podcast episodes. Thank you for listening.]