[MUSIC] Hello, my name is Frank Lin, and I am a E N T Surgeon, and an Epidemiologist at Johns Hopkins University, where I direct the cochlear Center for Hearing and Public health. And I want to thank you for joining me for this lecture today, entitled Aging, Hearing, and Public health. This section will cover essentially the rationale, and broader guiding questions for why we even think about studying Aging and Hearing in the context of Public Health. To begin with the reason why we study this, and why we think it's important, is really because this figure here on the left, and this figure comes from the United Nations, and it shows the number of adults who are 16 older, around the world. And we look right now, it's roughly about a billion older adults. And we see essentially over the next 30 years, we're going to see the population of older adults older than 60 double from about one billion, to two billion, in the next 30 years. And this is remarkable, for many of us we realized this has never happened before in 200,000 years of human civilization. We've never had, more older adults than than young children. And yet this is exactly what we're seeing, that's going to happen over the next 30 years. And for many of us, we realize why this happened. It's essentially happened because we've moved through two different eras of public health just in the last 100 years. For the first time in human civilization, about in the early 20th century, we began controlling, infectious, and communicable diseases for the first time in human history. And the leading killer of all of mankind, tuberculosis now, is still an issue, but it's well controlled as well as a host of other infectious diseases. Then, throughout the 20th century, we began dealing with the chronic diseases, the noncommunicable diseases, heart disease, cancers, which are still now the leading killer, of mankind and adults. But increasing as you can imagine, are increasingly coming under control. And the reason why we know this is, because again, this figure on the left. This figure demonstrating essentially a doubling of the world's population over the next 30 years older than 60, is the direct result now of 100 years of public health advances. So, many people would ask now, are we entering a third era of public health? Name the third era focused on aging prophecies, namely, if we ever got through the first two errors, were able to control communicable and noncommunicable diseases. This third era now we're dealing with essentially two billion adults older than 60 years old. What are the processes that we can target their, from a public health standpoint, to optimize the health and functioning of an aging population? Which is very, very different, than just controlling disease. What got us this point now, how then do we optimize the health of an aging population? Now, in that context, you can think about this, and some of these are pretty intuitive, is that there are broadly some health and policy strategies we can think about for optimizing healthy aging. Obviously we want to prevent and delay disease, mainly want to compress morbidity, until the very end of life. So if someone's not having a chronic disease over 30, 40 years of life, likewise, obviously, if you have disease, we want to be able to manage multi morbidity a lot of times, you may not have diabetes, you have cancer, they have heart disease. How do you manage all at once? And then clearly, there's a lot of public health research focus on lifestyle factors, diet, physical activity, for what can be optimal for allowing for ideal healthy agent. And finally, a lot of people, a lot of our colleagues in aging biology will study the actual underlying biological processes with underlying aging. In the future there may in fact be future drugs, which could target specific aging processes, to hopefully reduce muscle loss, optimize heart function, things like that clue. There'll never be a drug to live forever. But there could be drugs that can optimize certain systems in the body. Now, you realize these top four items, essentially form the bulk of a lot of public health research now focus on aging. And this last item I've listened here, namely optimizing sensory function almost seems a little stuck on. I mean, it's not too clear evidently, why would this be important. Now, the reason why we're increasing understanding that optimizing sensory function be critical, for healthy aging, and its third heir of public health, really comes from, which is a very traditional biomedical model of research. So we start with, it's a very classical model where the brain in the center is the most important organ in the body, for for obvious reasons. It's the only organ that you can't replace right? You can replace your heart, you can replace your lungs, you can place your liver, but you can't replace your brain for obvious reasons. So the brain is the most important organ in the body. And ultimately, then, no matter what you study, you care about how the brain allows us to do all these wonderful things, to think, to socialize, to do our physical activities. A lot of biomedical research focused on now then is how these pathways interact between our brain, our organ systems lines, to do what we want to do. And then also the diseases and the risk factors which may affect these relationships. And this is really the bulk of research. But what often people forget now, is that the brain the most important borg in the body, is literally isolated in your skull case, right? It doesn't have any access to the outside world. And the only way, the brain perceives the world around it, is through these main five sensory affair input systems, mainly sense of touch, hearing, vision, smell, and taste. There's some other ones as well, but these are the main ones that are important. So we forget a lot of times that our brain itself is isolated the in the skull, and it's not for the senses. You can still be alive, but you're not really alive per se, I would argue. So these sensory adherence or what provides all the input to the brain, and also allows that there's all these sort of wonderful things down here, whether we're thinking and using a computer, on the left or were socializing with our our spouse in a restaurant, or we're doing activity. Our senses essentially media and allows to all these processes. Now, importantly, when you're younger, and these senses all work, you don't really need to consider it from a public health or health standpoint. But as we get older, and some of these senses begin to decline for various biological reasons, they can argue become increasingly important. So the fundamental premise, that I approach a lot of my research within the center I direct at Hopkins, is our fundamental clinical belief that comes from our clinical experiences caring for patients, is that our ability to hear and engage with the people and environment around us is absolutely fundamental to our health and well being. And the reason why this is important again, in in younger adults, you don't think about as much because as you can see here on the right figure, this is a figure demonstrating the prevalence of hearing loss, a clinically significant hearing loss, by decade of life. And you see in the very early age is essentially just a couple percent at best. But then with every age, decade of life we see the prevalence of hearing loss nearly doubling, so that by the time we look at people are 70 above, that nearly 2/3 everyone over 70 has a meaningful hearing loss. So, when you're focused on early life and midlife, as we were 100 years ago with public health, center impairments weren't really that much of an issue. But as we have a large population of older adults now who are 60, 70, 80, the vast majority of you will have a hearing loss, is that when hearing becomes an increasingly important determinant, we think of how people can age in a successful and healthy way. Importantly, you can realize that this is something that could be empirically tested. So, a lot of the critical guiding questions, that guide how we think about hearing loss and aging, and public health, are shaped by these very, very basic questions. The first question, I mean, hearing loss is so common, almost everyone has it. Are there any actual meaningful consequences of hearing loss, for older adults? You realize the answer that basic question, is you have to draw on epidemiology, and health economics to answer this very, very basic root cause question. The second question then, which is even more important is well, if let's say there are some consequences of hearing loss for older adults, what's the impact of our therapeutics that currently treat hearing loss? Do they in fact make a difference? Do they reduce the risk of these outcomes that might be tied with hearing loss? And you realize the answer to that question, you have to do clinical trials, randomized clinical trials, testings intervention to see in fact, do they have an impact on preventing these critical outcomes? And finally, the third most important question, is that as in the slide I showed you before, if two thirds everyone over 70 has a hearing loss, how can we even effectively address hearing loss as a public health issue, if nearly everyone has it, who's older? How do you do that from a societal perspective without bankrupt the system, without having thousands and thousands of healthcare providers? How do you do it? And you realize then to address it societally, the only way that can be done is through effective public policy. We need to develop new approaches to hearing care. And we finally implementation science. How do we actually invoke, and put together and put forward already policies that work? And how do we actually make them work in a real world setting? So, these questions are essentially what guides a lot of hearing loss, and aging public health research. Now, what's interesting though is you realize that these questions also, reveal a paradox, and how we think about hearing loss. And what I mean by this is that how we think about hearing loss in children, versus an older adult, there's a complete and total paradox, and how we approach from a clinical and public health perspective. So, on the right figure here, this is an audio graham, and what this audio graham is that shows someone's hearing testing. And just summarize briefly, this hearing tests basically shows, a person who has essentially a mild, maybe a moderate hearing loss in both ears. And, the interesting thing about this hearing test, is if you show this hearing test to any clinician, or public health person who understands hearing loss will say, and this hearing loss, you say it belonged to this girl here on the far left, who is a young, 10 year old girl. Everyone would agree this hearing loss is absolutely critical for this 10 year old girl, because it could interfere with how she communicates on the playground, how well she can hear teachers and friends. And because of this, in many states, United States, many countries around the world now, hearing care is covered for Children that we do universal newborn hearing screen for Children. It is considered critical issue. Yet the amazing thing though is all of a sudden now if we said, well let's say this hearing test belong not to this 10 year old girl on the left, but this middle figure, an older man, who is maybe 75 years old, and this audio graham now belongs to him, I can almost assure you, if you ask a lot of clinicians the same question, you might get a lot of shrugs saying, he has a mild hearing loss, but a lot of people do his age, you could do something about it if you want. So, there is a fundamental paradox at the same hearing loss, the same functional impact upon hearing communication, critical for a 10 year old girl, not so critical for a 75 year old man. And the reason why I think we have this essential paradox, is because these same questions when applied to children, have essentially been pretty well answer over the last few decades, namely, the consequence of hearing loss for Children, well studied in terms of impact on education, of vocational opportunities in the future, employment, income in the future has all been well well studied. Likewise, there have been actually very good clinical trials testing, if you intervene on hearing loss in a child early, let's say with hearing aids, the impact it has on their educational and vocational attainment. And finally, addressing hearing loss in Children sidedly, it's a well studied, that's why we have universal newborn hearing screening done now and essentially many, many parts of the world. But these same questions you realize when apply to adults, especially the older adults older than 60 70, are just now beginning to be answered. So, because these questions that remain unanswered in adults, is why there's this visceral feeling that the hearing loss doesn't really matter in adult, but it's critical for Children. [MUSIC]
