Breathing in Change: Allergies, Asthma, Immunology and a Warming Planet

Climate change is reshaping the landscape of allergy and immunology in ways that directly affect human health. In this episode, Jeffrey G. Demain, MD, FAAAAI, discusses how rising temperatures, shifting weather patterns and increased carbon dioxide levels are intensifying allergic diseases and altering immune responses worldwide.

Transcript

Rebecca Saff, MD, PhD, FAAAAI 0:11

And welcome to conversations on the world of allergy, a podcast produced by the American Academy of Allergy, Asthma & Immunology. I'm your host, Rebecca Saff. I'm a board certified allergist and immunologist and a fellowship director who always enjoys learning more about the exciting field of allergy immunology. Our podcast series will use interviews with thought leaders to keep you up to date on new developments and to review core topics. Today we will discuss how climate change is impacting allergic disease in our patients. Climate change is not a theoretical issue. It's a daily clinical reality reshaping the health of our patients. From longer pollen seasons and rising allergen levels to worsening air quality and the spread of new plant species to new areas. The effects are increasingly evident across the spectrum of allergic disease. We are pleased to welcome Dr. Jeffrey Domain to the podcast. Dr. Domain is a clinical professor at the University of Washington and an affiliate professor at the University of Alaska, Anchorage. He founded the Allergy Addison and Immunology Center of Alaska and now is the director of Lux Infusion and Immunology. He has served on the board of directors for the American Board of Allergy and Immunology, as well as held multiple roles within the Quad AI, including co-editor of the Quad AI's Ask the Expert. He has a special interest in insect allergy and the impacts of climate change on respiratory health. Dr. Domain, thank you so much for taking the time to join us today. And welcome to the podcast.

Jeffrey G. Demain, MD, FAAAAI 1:25

Thank you so much. And thank you for the introduction. And I really appreciate the invitation. And I look forward to this discussion. One of my favorite topics.

Rebecca Saff, MD, PhD, FAAAAI 1:33

Absolutely. Well, I'd like to start by getting to know you a little better. Can you tell us a little bit about yourself outside of your interest in medicine as well?

Jeffrey G. Demain, MD, FAAAAI 1:42

Well, I'm uh I've lived in Alaska. I've retired from the military, from the Air Force here. I've lived in Alaska now for we've here been here over 30 years. Uh I'm an avid outdoors man uh and particularly a very avid fly fisherman, and I travel near and far throughout Alaska as well as throughout the world uh fly fishing. Uh but you know what I have a tremendous amount of passion for what we what I do. I mean, so part of part of my passion is the work, is our field, allergy immunology. And I've been working with climate change uh really since 1990 or so, and that's really early 1900s, early 1990s, and that's because in Alaska we're watching it. I mean, we're our climate is in is accelerating three times what it is globally. So we are literally watching this happen in front of our eyes. It's like living in a museum a bit. Unfortunately, it's not good. So we're watching the shorelines fall into the into the sea, villages falling into the sea, permafrost melting. Uh, and with permafrost melting, you know, villages are turning into swamps essentially. Uh, you've got anyway, so we're we're watching these things occur and how it's impacting the way people live and people's lives. And so you you it's hard to not become passionate about it. And uh, and I also have a tremendous insect interest in insect allergy, and we were seeing significant rise in the number of patients coming in with insect anaphylaxis, and then we had two deaths from stings within four weeks of each other. So, myself, an entomologist, and the director of epidemiology got together and we did a study to look at that, and I'll talk about that later.

Rebecca Saff, MD, PhD, FAAAAI 3:31

Yeah. So I just want to start off by maybe you telling us about the definition of climate change and why it's occurring.

Jeffrey G. Demain, MD, FAAAAI 3:39

Well, the we people sometimes think about climate change as what the weather is outside. Well, that's weather. So, but you but if you step back and you look at climate variables, that you look at weather and you're looking at trends, and you're looking at trends over years or even decades, and then you look to see why is this weather changing? Why are we getting hotter? Why are we having more storms? Uh, and why are we having more droughts? Why are we seeing more fires? And so that's kind of the envelope of climate change. And as a result, we're we're when we're looking at some of those factors, we're realizing exactly what you said, Rebecca, and that is that we're not, this isn't something that's futuristic. This is something that we're experiencing right now. And we'll go through some of those data as we talk. But you know, we're probably since 19, well, 1950, we've had a significant acceleration in temperature as well as uh as well as CO2, as well as weather patterns. But this all began around 1870, at the uh pre-industrial revolution. So, and this is really directly tied to well-mixed greenhouse gases. Uh, and it's important that uh for us to be surviving, for us for people or any animals to live on this planet, you have to have the greenhouse effect. Otherwise, we couldn't we couldn't survive. So, with greenhouse effect is that when heat comes in through the from the sun, radiated in, you get re re-radiation back out, it kind of bounces back out. Well, with this greenhouse gas, it keeps some of that heat in and it bounces back to Earth. So that's what keeps our temperature regulated, so to speak. But as the amount of greenhouse gas grows and becomes more dense and becomes you know a larger percentage, now you've got re-radiated heat, all re not all, but most of the re-radiated heat is staying. So we're keeping more and more of that solar irradiation within our atmosphere.

Rebecca Saff, MD, PhD, FAAAAI 5:46

It sounds like that increased that increased temperature, even though small on a kind of a daily basis, is making a huge effect over time.

Jeffrey G. Demain, MD, FAAAAI 5:54

Oh, yes, absolutely. Tremendous event. And it's going to be significantly more impactful the further south or the further north you go. So realize we're we're now at 1.5 degrees Celsius. Uh we've warmed. Uh, and that doesn't sound like much, but it is. But again, when you start moving north and south to the to the toward the poles, that's three times that that amount. So, and so it's gonna be different whether you're in Houston, Texas, or whether you're gonna be in New England, or whether you're gonna be in Canada or Alaska. So it's gonna change. Uh, and all the studies that have been done have actually shown that latitude makes a very big difference as far as acceleration of heat. And in the past decade, uh, well now we're we're now in our current decade, we've accelerated twice as fast as the previous decade. So this is almost it kind of compounds on itself. You know, you melt sea ice and now you have water, and and water takes up the heat. Uh, you're losing that reflectibility back, so it's being retained. Uh, and then you melt permafrost, you have more methane release. That's contributing more to the greenhouse gases. So, you know, as these things occur, we start seeing, you know, again, kind of compounding effects. Uh, and we're seeing the sea the sea uh level rise as a result, big result of the melting glaciers and uh predominantly. And uh anyway, so big things happening in the Antarctic right now, too, as far as one of the major glaciers is thought to be uh melting and we'll lose it. But anyway, so that's that's climate change.

Rebecca Saff, MD, PhD, FAAAAI 7:42

So one of the most recognizable aspects of climate change for allergists is the changing of the pollen seasons. We're now seeing these um increased pollen lengths, increased pollen heights. Can you tell us more about kind of what we're seeing in terms of the effect on pollen?

Jeffrey G. Demain, MD, FAAAAI 7:56

Yeah, uh, if I may, I'm gonna kind of talk about a couple of studies. Uh they're really landmark studies. Louis Ziska did these studies when he was at Duke. He's now currently at Columbia. Uh, but brilliant. He's done just truly brilliant work. And he he originally took ragweed and he planted, he had vessels. All the variables were controlled, and the only thing he did was change the CO2 level for this ragweed to grow. Uh and he looked at ragweed with the CO2 level of 280 parts per million, that was kind of pre-industrial, at 370 parts per million, which was what it was in 2000, and then uh at 600 parts per million, which was projected to be at 2100, now projected to be at 2050. Uh, and what he found is that the ragweed from 280 to 370, it it accelerated in biomass 132%. And then uh at 600, it accelerated another 90 percent. So that that was pretty astounding. And then he took it to the field and then in rural Baltimore, suburban Baltimore, and urban Baltimore. Now, urban Baltimore is two degrees Celsius warmer than rural, and it has 30% more CO2. That's called a heat island effect. Uh so he planted ragweed again plants in each of those areas, and then when he harvested those plants, he was looking again at biomass change. From rural to suburban, it had increased 66%. From rural to urban, it increased 189%. So that was looking at ragweed biomass and pollen. And then from that, there's been beautiful work done by J1O in South Korea, where he did very much the same thing, had these vessels with all variables controlled and grew ragweed. But what he did is every two weeks he harvested the pollen. And the pollen was put in aliquots, so measured in aliquots. Uh, and so what they did at the end, he measured ambe 1 and he measured it at uh 380, 500, 600, and 1000 CO2. So the ambient one from 380 to 500, which we're close to now, went up 67%. Ambe 1 per aliquant to 600 went up 40, another 41%, and then at 1,000 it went up another 20%. So now we're talking about more pollen, and we're talking about more ambi 1 per pollen amount per aliquant. And then this goes one step further where when you look at CO2, you look at biomass or protein, you look at ambe 1, you put that together, that it with a CO2 of 280, that's 100 milligrams of ambi 1 per plant. CO2 at 370 is 250 milligrams of ambi 1 per plant. CO2 of 600, 850 milligrams of ambient one per plant. So that, you know, what you're seeing is again this acceleration that's going up. So the CO2 is absolutely a driver, and it's altering the carbon-nitrogen ratio as well. And again, I might touch on that a little bit later. But we're also seeing seasoning, seasonal links, and I don't know if you want to chat on that too. But uh I want to add one other one other comment on this isn't ragweed, but I want to talk about oak um on trees. So we're seeing the same thing on trees. Unbelievable, Joe J10 in South Korea did the same model with oak trees. He planted two oak trees in these humongous chambers, and he maintained all variables the same except CO2. Same model. And he measured it with QA1, the allergen associated with oak, and really showed it was really the same type of association. Oak pollen had much more allergenicity, in addition to much more pollen. And actually, he he did, I'm trying to remember the number, but it's pretty astounding uh what happened with the uh with the oak pollen, and when you calculate the catkins uh and you calculate the QA1. So, anyway, that that would be kind of when you're talking about what is it doing to pollens. Uh, but then you look at seasoning, and some very good studies have been done looking at that. There was one where all of the National Allergy Bureau data were combined. So it was all pollens, all comers. And they looked at this over a period of 18 years, uh no, 20, 28 years, and just looked at the pollen levels, looked at the onset of seasons, looked at the duration of seasons, and they found all comers that the season length was additional 20 days, the pollen start date was 13 days earlier, and the end date was 17 days later. And that's because you have earlier frost off and later frost on, so to speak. So you're expanding your shoulders, you're expanding the length of your spring and your length of your uh fall. Uh and they found also it overall increased pollen concentrations of 21%. Uh and then uh Lou Ziska and Lynn Billeroy, they did a very nice study looking at cities starting in Texas going up to Saskatchewan, Canada, and were able to demonstrate over a period of I think this was 18 years, uh, increases in poll as you went north. So up to a point of Saskatchewan that was uh 27 days longer pollination duration. And so, and then EPA came back and looked for an additional four years, and with that additional four years, that duration had increased an additional four to five days. So that's really being driven by uh CO2 in combination with heat.

Rebecca Saff, MD, PhD, FAAAAI 13:48

And are you seeing different plants in Alaska, for example, now than you did when you started practicing there?

Jeffrey G. Demain, MD, FAAAAI 13:54

I don't know that I'm seeing different plants. I mean, because it's that's a good, really good question because honestly, I haven't looked. We don't have ragweed there. Uh I can tell you that our birch, our birch is the highest in the world. I mean, last year we this is we hit 4,000 grains per cubic meter. Uh I mean, that's a lot of birch.

Rebecca Saff, MD, PhD, FAAAAI 14:16

Uh I thought New England had a lot of birch, but that's that's a lot of birch.

Jeffrey G. Demain, MD, FAAAAI 14:20

And we have a lot of oral allergy syndrome as well, um and can be very significant. So I will say that in looking at our pollens, a couple of things we've seen, we've seen number one, I think our pollens are increasing. Number two, our seasons are are lengthening. And if I can make this kind of a little story, uh, we were we um a couple of years ago, three or four years ago, we realized, gee, it looks like we're on the downside of birch, what's going on? So we started putting out our burkhart trap earlier and earlier to a point where we were going out in snowshoes and setting up the burkhart trap because it's still warm. It's warm and sunny, and you need kind of five days of warm and sunny for them to start pollinating. But we didn't, we never thought if there's snow on the ground, it's not gonna pollinate. We were very wrong. So now we're now we're literally placing our burkhart traps uh uh during snow. Uh as long we're just waiting for those warm sunny days.

Rebecca Saff, MD, PhD, FAAAAI 15:20

There you go. And are you telling patients different? Are you giving patients different instructions with these longer seasons? Are you having them start the medications earlier? Are you seeing more patients come in needing you know immunotherapy in the setting of having these really high pollen levels?

Jeffrey G. Demain, MD, FAAAAI 15:35

Yes, we've you know, we I think we've definitely seen more people developing uh particularly birch allergy, but we have most everything here as well. Our grasses could be quite bad. Uh, and we have you know several weeds, but not ragweed, but we've got mugwart and English plantain and many others. So what we've what we've started doing is it when they were on sublingual immunotherapy, so now we're bringing them in three weeks earlier for some lingual immunotherapy, and in the fall, they're gonna three weeks longer for their sublingual immunotherapy. Uh so I think you have to make some adjustments. And if someone's on medications, we usually recommend that they start their medicine sooner because we're seeing these sooner. And we do we have two pollen counters in Anchorage that are run by my prior practice, and there's one in Fairbanks. So then these are published on the news. Uh, if someone watches the local news, it's published on our website, it's on the municipal website. So people have access to that. And we've certainly encouraged patients to to monitor that, not only just for the uh for the uh pollens, but also we recommend monitoring air quality index too.

Rebecca Saff, MD, PhD, FAAAAI 16:47

And it used to be, it sounds like the advice would be to wait until you know the snow started to melt before we're really seeing pollen. Now we know even though there's snow on the ground and it's cold, you gotta start your medications even then.

Jeffrey G. Demain, MD, FAAAAI 16:58

That's right. And and we're finding it sooner, you know. So uh yes, I I think so. We've had to adjust. Certainly, we're we're we're starting sooner. Absolutely. Now, this year, probably not. We've had a very unusual, uh, unusually cold year. We're usually not that cold here in south central Alaska, but this one has been kind of a harder later winter. So this year probably will be look will be like the old normal.

Rebecca Saff, MD, PhD, FAAAAI 17:26

Wait, what is it not that cold or is that cold mean in Alaska? I'm just curious.

Jeffrey G. Demain, MD, FAAAAI 17:31

Okay, our average where I am in uh South Central, our average winter temperature is about 24. So you're gonna have you're gonna have a few weeks around zero, and then you're gonna have unfortunately a few weeks around 40. Uh, but but it averages out to about 24. This year has been definitely chillier, but we've had plenty of snow, a lot of snow, so that the snow really is very protective for plants and so forth. But you know, one to make another comment. We've had melting permafrost, I mentioned that, and now we're seeing trees where there were never trees before. There are now trees growing 110 miles from the Arctic Ocean. They're not big trees, but they're trees. So, and it is causing some problems. The in in the interior, the rivers are the roads. There are no roads. So that people travel by boat or snow machine on the rivers. Well, with trees growing, now beavers have moved in, and they're building beaver lodges and causing uh erosion uh in the around the soils and really kind of causing a navigational mess up there. So, you know, it it has there's there's this kind of compounding effect of how this happens. But yeah, it's uh really pretty interesting. Another thing is happening, we're seeing a shift between we were always always conifer predominant uh evergreens, mainly spruce and hemlock. And we're and but now we've gone through a shift where we've become uh uh deciduous tree predominant. So that kind of happened around 2010 or so, where we actually crossed that line. So uh another thing, so you were seeing certainly changes uh in our flora and fauna, but I I can't say that I've seen uh new plants, but I certainly that's happened in other areas.

Rebecca Saff, MD, PhD, FAAAAI 19:23

Yeah. So in terms of the increased pollution and its effect on allergic rhinitis and asthma, how does it actually affect the airway?

Jeffrey G. Demain, MD, FAAAAI 19:31

Oh wow, that's a that's a big question. Uh so how does the so pollution affects kind of the upper and lower airway similarly, but of course the downstream effect is going to be more severe with the up with the lower airway. But the the big thing pollution does is really two, you're gonna have significant disruption of the epithelial barrier. So that creates much more permeability. Uh, so you're gonna have not only the allergens that can enter and be picked up by the by the dendritic cells, but you've got what what what is called agglomeration, where you have these pollutants will bind to the pollens, you know, mainly carbon will bind to the pollens and you make these agglomerated particles. And so these are inhaled deeply into the lungs, so you're having an impact of a significantly more intense on not only allergic response but inflammatory response. But when you have this barrier disruption, uh you you're gonna activate alarmins, and that's gonna be like your TSLP, IL-33, IL25, and then that's gonna activate our cells, neutrophils as well as eosinophils and lymphocytes. So then you get your cytokine release, which is gonna be IL-4, L5, IL-13, IL6, TNF alpha, and IL1 beta. So then that's gonna, from there, you're gonna you're gonna activate both TH2 high as well as TH2 low inflammatory response. So what we're there there are data that show not only does it intensify the asthma and the allergic rhinitis, but it can increase the development of it. So when we look at asthma going, you know, rising in throughout the world and allergic rhinitis probably likely rising throughout the world, that was based on Isaac data some a couple of decades ago, actually, well, decade ago. So I think that that's one of the things that can certainly play a role. There are some data showing that that allergic rhinitis can increase as much uh as uh odds ratio of 1.4 in high polluted areas. So there have been there was a one, there was a systemic re a systematic review and meta-analysis that that demonstrated that. And there, you know, there's other studies that say 1.14, or you know, so there's variability depending on uh you know what they're looking at, what are the variables, but it's very difficult to you. You can't control all the variables in the environment. You can if you're inside a chamber, but you can't. So it makes it difficult to measure. But so you're going to have not only inflammatory response, you're going to have an allergic inflammatory response, you're going to see more exacerbations, more hospitalizations, you're going to see a significant decrease in quality of life, more medication use, as well as increased health care costs. So the pollution definitely plays a very substantial role, worsening and provoking and even maybe causing asthma. But there was a study, it was done by a Dr. Ariano in Italy, and this was a 27-year study, where what he did is he was doing skin tests on his patients and managing patients. So he was he had a certain percentage of patients that were allergic to polls like olive pollen, and he had a certain percentage related to dust mite. So he looked at trees, grasses, and weeds, and he used as his control dust mites since that's perennial. And then he monitored over 27 years, he monitored uh the temperature, rainfall, uh solar irradiation, and I can't remember the rest. But so what he what they ultimately found though is over that 27 years, when he went back and looked at these data, the number of patients that he had, like, for example, allergic to olive significantly increased. I mean, it was very like 30% higher. When you looked at the percentage of patients he had to dust mite, there was no change at all. So that was one study that actually gave some evidence that you know some of these variables certainly could increase the likelihood of developing. Oh, he also measured pollen levels and see season, seasonal length and pollen levels for the other things too. And it correlated with the rise in the pollen levels that he saw, but dust mite didn't rise. So that kind of took those variables and gave it at least some degree of connection to you know, does this impact or increase the probability of developing allergy?

Rebecca Saff, MD, PhD, FAAAAI 24:10

It seems like there is this significant increase in multiple different kinds of plants. Are there plants we're actually seeing decrease in this kind of with the the changing CO2 levels and the changing climate?

Jeffrey G. Demain, MD, FAAAAI 24:22

The answer to the decrease, no. There are some that are not as affected. So when studies have been done looking at ribosomal plants, and ribosomal plants really don't have much impact uh with the CO2 levels, but there's none that I know of that are going down. Uh, you know, there may be some plants that are maybe more heat sensitive, uh, but again, those plants are are gonna are gonna move as the as our ecosystems change, you know. So, you know, when it gets warmer across the street, they're gonna go there, uh, kind of thing. So uh but I don't know if any going. Absolutely, absolutely. Well, they're also the ones we're studying. I mean, uh, but you can take away some of the allergenic plants and poison ivy. Poison ivy's been studied in that environment too. And in in when you raise the CO2, the poison ivy biomass goes up 50% compared to 100%. So about a 50% increase. And then the the the unabsorbed uroschol, which is what causes the blistering on your skin, that increases 75% uh in the plant. So you get larger poison ivy plants, and you get uh and you have increased toxicity of the plant. So even stepping away from the pollinating plants, there's gonna be involvement as well. You know, foods are impacted as well. Uh, we might chat about that a little later, but or we're gonna talk about it now.

Rebecca Saff, MD, PhD, FAAAAI 25:57

This is there's actually a change in the actual protein content, I think, in some plants that we use for foods with the the changes in the temperature and with the CO2 levels.

Jeffrey G. Demain, MD, FAAAAI 26:06

Yes, absolutely. There was a one where they looked at cassava, uh, and they again, the same kind of thing, 350 CO2 versus 700 CO2 in this study. And the cassava is a very important plant for they they make a flower out of it, very important in in Latin America and Asia, and I think it's the third, one of the third leading sources of carbohydrate. But the cassava plant, it's a root, a tuber. It was 80% smaller in the hike CO2 versus the normal CO2. And in addition, it increases the cyanoglycosides, basically uh cyanide, it increased cyanide in the plant, so it made it potentially more toxic. And there's also been a lot of data looking at food as far as uh nutrition. So in these high CO2 environments, you have 11% decrease in protein and rice, you have decrease in in maize, you have a decrease in corn, you have a decrease in wheat. Uh it doesn't affect legumes, but all of them have decreases in zinc and decreases in iron. So you're gonna have lower nutritional value of some very important plants, uh, especially rice. I mean, think about how important rice is nutritionally around the world. So there's a you know, I suspect they're gonna there's gonna be some you know able some ability to modify these genetically, but you brought that up. You're exactly right. What's changing is the ratio between carbon and nitrogen in these plants and high uh in these high car CO2 levels. Uh so it's impacting the plants, and quite frankly, I think it's impacting the the proteins, and maybe my guess thought is that it this may be part of why we're seeing more food allergies. I think we're probably changing those proteins in certain foods that may be associated with higher risk of food allergy. That's just my thought, but I'm I'm pretty certain that the protein uh component is changing.

Rebecca Saff, MD, PhD, FAAAAI 28:15

I definitely think that's probably one of the components. I think food allergy is this interesting, all these different factors on top of each other that have led to this. But absolutely the changes in foods. We know that you know boiling peanuts versus dry roasting them makes a difference in their allergenicity. So just you know changing the the heating changes in the protein content, I imagine it makes a huge difference.

Jeffrey G. Demain, MD, FAAAAI 28:37

Yeah, I think so too. Anyway, but but it it it definitely has uh it's definitely been an association with food allergy. Uh but yeah, so we'll we'll talk about that.

Rebecca Saff, MD, PhD, FAAAAI 28:48

So, what about extreme weather events? So that's certainly something that can impact allergic diseases. How is that impacting our patients?

Jeffrey G. Demain, MD, FAAAAI 28:55

Well, extreme weather, a lot of that is occurring because of warming waters. And uh the the water, the oceans are like a big air conditioner. Uh they circulate uh and these oscillating circulations, they really travel throughout the globe. So as you have more warming water, because now you've got more heat, irradiated heat from the sun being absorbed as opposed to being reflected back, uh, this warming water is provoking greater storms. And that warming water, you get more vaporization, more uptake into the clouds. So we're starting to see more severe storms, of course. We obviously have seen many severe hurricanes, uh, and they seem to be getting worse and worse. Uh the tornadoes, I'm not, I don't really have an I don't know the association with climate change and tornadoes, so I'll I'll pull that one back. There might be, I just haven't studied that. Uh, but certainly we're seeing it more with flooding, uh, as extreme weather as well. And flooding uh clearly has association with uh development of molds, and there you're back to respiratory disease, upper and lower. Uh, but it also has association with atopic dermatitis and flares as well with flooding. That's been pretty well demonstrated, too. The association with drought uh that is kind of kind of part of the I wouldn't call that a severe storm, but it's also an impact of these weather changes. Uh, you're gonna see much more in the way of wildfires. And most wildfires, most, certainly where I live, are initiated by lightning strikes. So, again, if you have more of these thunderstorms, you're gonna have uh greater risk of wildfires, and you know, wildfire smoke can be quite devastating. Um, then finally, you we're all familiar, I think, with thunderstorm asthma, uh, where the grass particles are pulled up into the storm, and through osmotic challenges as long as well as humidity, they rupture, and then these fine particles, uh allergenic particles are released. They're much smaller than 2.5 mics. So they're they're inhaled very deeply into the lung and have been associated with tremendous increase in exacerbations, emergency department visits, severe uh asthma events requiring hospitalization and even deaths. And that have been they've been most well studied with a huge event that occurred in Melbourne. There was also a very interesting study done uh with an event that occurred in Walla Walla, Australia. So, anyway, that yeah, Thunder, then that Dr. Diamato has really defined that. I mean, that's his, you know, really one of his strongest research. He's done most of the a lot of the research on that and very impressive work.

Rebecca Saff, MD, PhD, FAAAAI 31:35

Yeah. And are you giving patients with asthma different advice on, for example, on days when the CO2 levels are higher, or the pollution levels are higher, or we know there's gonna be wildfires. How do you advise patients in those situations?

Jeffrey G. Demain, MD, FAAAAI 31:48

Right. Again, really good question. Um, that that's gonna have to be observational, number one. We want them to be indoors. If we see air quality indexes that are greater than 100, we recommend that they try to stay indoors or wear a mask when they're outdoors. If the air quality index starts increasing greater than 200, uh, we recommend that you know they may consider leaving the area. Uh, you know, depending on, you know, so uh we don't have the the fossil fuel burning pollution at like like we may have on the East Coast, but we do have some of that. But our the our little biggest uh issues with pollution are volcanic eruptions and uh and wildfires. And we have a lot of wildfires. You know, we burn probably a couple of million acres a year burned from in the in the interior. So uh understanding the air quality index that's important, and so we we recommend HEPA filters. HEPA filters have been shown uh to be really quite effective in reducing the pollutants inside the home. Actually, I'm working with the World Alger Organization right now. We're working on a on uh manuscript and we'll be looking at exactly that. So stay tuned, and that'll be coming out. And then uh we we also recommend closing windows and doors when the pollution is high outside, uh, and and again minimizing minimizing going in and out. So, you know, there's uh beyond that it's difficult, but you also have issues with heat, uh, and that's a problem too. So, you know, air air conditioning is you know, you want to, if you don't have air conditioning and it's getting too hot, you want to be able to go to a cooling building, a cooling uh center, and we have those even now in Alaska. Uh, we're starting to see temperatures that are 80, and 80 feels like 110 here. Uh we're more typically in the mid-60s to mid-70s, but we're starting to see those 80 degree temperatures. So those are kind of the recommendations. I think really being aware, making sure they're using their medications appropriately, uh, trying to minimize the exposure to the pollutants. And if the if you know, we again with wildfires, there was one fire called the mission fire where the air quality index went to over a thousand. Over a thousand. It's kind of insane. You know, it stops at 300, I think. Uh, you know, I think that's a ceiling, 300 or 400, but this went to a thousand as far as their their levels.

Rebecca Saff, MD, PhD, FAAAAI 34:14

Uh so who measures the air quality index? Do you know?

Jeffrey G. Demain, MD, FAAAAI 34:17

Yeah, it's done through it's done through the municipal municipality measures it, and there there's it's like NOAA measures it. There's there's federal units that measure it. Yeah, that's a good question. Um, the municipality publishes it, and I I would think probably NOAA, and I would think there's air quality stations um just like we have pollen stations. Uh I don't know. I don't know. Good question. I need to find out. Uh I so when you look at air quality index, um, I could I can tell you what they're looking at. So they're they're looking at ozone, they're measuring particulate matter, PM 2.5 and PM uh PM10, they're measuring um, I think it's carbon monoxide. But ozone is a major factor for what they're measuring. Um but so those are really the biggies. The ozone, oh, they're measuring nitrogen dioxide, sulfur dioxide, PM2.5, PM10, and ozone. Those are the five things they're measuring.

Rebecca Saff, MD, PhD, FAAAAI 35:22

Then we as physicians, we want to help our patients, but there's actually some pollution from, well, I mean, the whole healthcare industry, um, but from the inhaler itself, that can actually increase carbon emissions. Is that right?

Jeffrey G. Demain, MD, FAAAAI 35:33

Yes, that's really very interesting. Again, we're looking at that too. So to give you in in in the Montreal Protocol in 1984 banned carb uh CFC, chlorofluorocarbon. And it's really interesting. There it they show when we look at pollutants, you there's the that's the only line going down, which was really great. So that what that did is it closed our ozone. We had a hole in the now ozone's good when it's in the stratosphere, it's not good in our atmosphere. So the uh it we were able to close that ozone hole with the re with removal, but unfortunately, what was replaced with our inhalers is still has a carbon footprint, so to speak. And but then the Kyoto Protocol in 1997 said that the hydrofluorocarbons should be phased out, and then there was an amendment to the Montreal protocol in 2024 that requires phasing down hydrofluorocarbons. But to kind of get an idea, the the an a meter dose inhaler for a year, this is in the in the UK, the the use of a meter dose inhalers by a patient for a meter dose inhalers in the UK uh is equivalent to 610,000 diesel cars in a year. But now I'm talking about all meter dose inhalers, all you know, if you count all the meter dose inhalers, because even if they don't completely finish it, it's going to eventually release. It's going to release if it's in a in a landfill or whatever. The MDI is significantly higher. I mean, tremendous, you know, the the DPI has almost no risk, no, it's 200 fold less. It has a little bit, but not much. So uh it makes up the meter dose inhalers make up about 3% of our health-related carbon footprint, or really about 0.1% of the total uh carbon footprint of all. So it's it's not huge, uh, but it it it's equivalent to 2,500 kilotons of carbon per year. So it's not little, and really everything we can do can make a difference. So I think you know, there there needs to be number one development of a propellant that is not fluorocarbon or hydrocarbon, and also maybe an increased use of dpi when appropriate. Obviously, a small child can't do it. Um, maybe somebody that doesn't have good air volume may not be able to effectively do a DPI. So there it doesn't mean that it needs to be all everything, everything else needs to go away. I think we just need to come up with alternatives that aren't damaging our environment.

Rebecca Saff, MD, PhD, FAAAAI 38:14

I think there's even a study that shows that if you talk to patients about kind of the differences between HFAs and DPIs, that they'll choose DPIs because of the environmental impact as long as they're getting good benefit from it.

Jeffrey G. Demain, MD, FAAAAI 38:26

Yeah. Yeah, that's and that's I don't think I read that study, but that's that's good. I would I'm not doubting it. People people are aware, uh, and they're becoming more aware. I don't think we have nearly the number of climate deniers that we had 20 years ago. Yeah, it's a neutral sound.

Rebecca Saff, MD, PhD, FAAAAI 38:44

It's hard to deny when you can see the effects.

Jeffrey G. Demain, MD, FAAAAI 38:46

So right, right. Well, yeah, you got a lot of the Canadian uh smoke, didn't you?

Rebecca Saff, MD, PhD, FAAAAI 38:53

Up in the in the last couple of years, we've had a lot of the Canadian wildfire smoke come down the East Coast, and definitely we see the impact on our asthma patients, there's no question.

Jeffrey G. Demain, MD, FAAAAI 39:02

Yeah, yeah. So you know I think it's something we are we are all seeing. Yeah, it's something we're you know that's really quite tangible. Uh and and it's going to get worse. That's the that's the problem. You know, it's gonna keep it's accelerating, uh, unfortunately. But you know, you you guys can always come to Alaska. Well, we we we try to keep our air clean.

Rebecca Saff, MD, PhD, FAAAAI 39:25

Well, you're not gonna keep it clean if we all move there, so you know.

Jeffrey G. Demain, MD, FAAAAI 39:29

Oh yeah, you you you can't bring your cars.

Rebecca Saff, MD, PhD, FAAAAI 39:32

No, thank you. Um so for for physicians who want to do something that's that's helpful, are there certain prescribing practices or certain things that we can do um that can impact climate change?

Jeffrey G. Demain, MD, FAAAAI 39:45

Uh yeah, I think there there are. I think, you know, number one, I think it's you know, we can certainly talk to patients about lifestyle. Uh and lifestyle might mean riding the bike instead of driving your car, uh, or taking public transportation rather than driving the car. So, I mean, that's one. Uh, and also lifestyle is in area in times of high pollution or high pollen, you know, maybe seek indoors. Uh, I think we can recommend um you're we're trying to decrease pollution. So again, maybe encourage your doctor to give you a DPI instead of a meter dose inhaler. I think other things that we can do is kind of you know, talk, walk the talk, so to speak. You know, if we we should recycle, we should try to minimize waste. We you know, do our best to, you know, if I'm not in an environment where electric cars would are very helpful, but certainly a lot of areas are, and and maybe electric vehicles, uh, I think that can certainly help reduce you know some of the emissions. So I think a lot of it is going to come down to lifestyle. I think one of the most important things we can do as physicians is be advocates, uh, because you know, physicians still uh are leaders in the community and and and people listen. And so if if we can advocate for taking steps toward mitigation uh of climate change, I think that's something that would be very helpful. And if we have our patients, you know, tell them how important that is. Uh, because I think that it's the word of the people that really make it we can make a big difference. So I think it's you know, try to try your best to, and if everybody did something in their small way, uh, I think you know there's gonna be overall there's gonna be a little bit turns into a lot when you have you know a lot of people doing it. So as far as what can what can patients do, yeah, that I think it's limited, but I think it's gonna be primarily livestock. You can, you know, they can eat more of a plant-based diet instead of an animal-based diet. The uh, you know, livestock uh uh contribute nine percent of our greenhouse gas, uh primarily in the form of methane. Uh so less livestock would you know as in use plants instead. But you know, growing agriculture, you know, it has its own climate change impact, but not as much as livestock. So that would be another thing you know you could suggest. But that's probably I think there are probably limits beyond that.

Rebecca Saff, MD, PhD, FAAAAI 42:20

Yeah. The healthcare industry as a whole actually really contributes to um to pollution um because of all of the medical waste, because of all of the carbon dioxide production. Um, are there moves now in healthcare to try to make us more carbon neutral?

Jeffrey G. Demain, MD, FAAAAI 42:37

Yeah, I think you're right. I'm gonna use an example here. I think one of the big areas is anesthetic gases. So when you're using uh uh one for one hour of surgery or one hour surgery, uh nitrous oxide that's used is is equivalent to driving a car 65 miles. So if you use desplurane as your parallel as your as your agent, it's equivalent to driving a car 248 miles for an hour. So if it's substituted for sevofluorane, then it's like driving six miles. So you know, making a change in the in the gases that we use and anesthesia, you know, that's that's an even bigger impact than you know us, you know, maybe trying to dial back the use of meter dose inhalers. So I think that's a big one, but you're right. Uh a lot the carbon, the carbon footprint of healthcare is about 8.5% of the total. Uh, so that's significant. It's a but it that that comes down to the energy we use to run our hospitals. That comes down to if we you know we have an ambulance service, the driving that we do, you know, you know, even bringing in supplies. So you start adding up you know energy and you start adding up you know automobiles and and ambulances. And off-gassing. So that kind of what makes up most of the healthcare. So again, what could you do? In the proper environment, maybe move more toward uh non-fossil fuel burning cars and ambulances. So that would be something pretty easy to do when you're the next time they're upgrading that. You'll try to encourage their distributors to do that as well. And I, you know, Amazon's doing that. You know, there are definitely industries that are doing it now. So try to try to encourage you know burning less fossil fuel. Uh as far as heating or air conditioning of building, uh, a little difficult. You know, certainly I'm certainly hoping they're not burning coal. Natural gas is probably the cleanest fossil fuel, but you know, I don't know that we're at a point yet where we you would get adequate uh adequate energy from a wind farm, uh, maybe, but yeah, that would take a pretty big wind farm or a pretty big solar farm. So I think looking for alternatives would be good. So you know, again, if if you could reduce the off-gassing 20%, I mean that's pretty good. So you take it down the we contribute six percent. Um, so yeah, it's gonna be a large difference.

Rebecca Saff, MD, PhD, FAAAAI 45:16

Over the kind of large number of people and over you know, kind of over time. So you know, we have to take the small wins too.

Jeffrey G. Demain, MD, FAAAAI 45:24

That's right, that's right. And that's what's exciting when we took away the the CFCs. That was a win. You could see it, very measurable win. Yeah, that was really good. Um the you know, I think you know, we can help also. Uh, you know, again, I I would recommend, you know, on even on all of our websites, you know, include things like, you know, what are not just what are our pollen levels, what's our air quality index, have information on climate change and how these things impact it. So, and I think we need to bring climate change into the education process. Actually, the World Health Organization in 2024 recommended that when training medical students, there should be a component on uh on climate change and the impact on health. You know, because we're really talking about allergies and asthma. You know, we haven't you know touched on many other things. I mean, how it impacts atopic dermatitis, how it infects food allergy, uh, how it, you know, how does it impact cardiovascular disease? You know, so these pollutants and and the impact of climate change really it really extends all the way through healthcare. Uh, and it the there are very vulnerable populations like the the children. Data have clearly shown that early exposures, you know, there's really an epigenetic change. And these children have a much higher risk of developing you know atopic dermatitis, food allergy, asthma allergy by the time they're three to four years old. So there's really compelling data showing that odds ratio is in the 1.3, 1.4, you know, range. So, you know, I think the young are very, very vulnerable. The old, the elderly are very vulnerable because they may have a limited uh ability to tolerate it because of ongoing cardiovascular disease. Then we've got marginalized individuals that may not be able to cool their house appropriately, they don't have a HEPA filter to reduce some of the pollutants that come into the home. Uh, and then you have uh athletes and and outdoor workers. You know, that's that's their business is to be outside. So you you have certain groups that I think have a greater degree of vulnerability. And again, that's outside of our discussion here. I'm not sure why I went down that rabbit hole, but it's certainly true.

Rebecca Saff, MD, PhD, FAAAAI 47:44

There are certainly patients that we have to be aware of who may not have the ability to stay inside because of the work that they do, or that you know, don't have the resources to you know cool their houses during heat waves. And so being certainly aware of the resources that our patients have and how that they can utilize them to stay safe with the changing weather.

Jeffrey G. Demain, MD, FAAAAI 48:02

Right, right, right, exactly. So, you know, so our adaptation is our short-term benefit for short-term goal, and not everybody can that can adapt. And if we look beside, look outside our borders, there are individuals that really have no options. Uh, and with rising sea levels are gonna be very significantly impacted, uh, and droughts very significantly impacted. Uh, and there's there's no options, they have they have no shelter. So uh yeah, I think this is we're we're still again, as the World Health Organization stated, that this is the greatest health crisis in our century.

Rebecca Saff, MD, PhD, FAAAAI 48:44

Well, I think that I loved how you brought both the kind of hard message of climate change and its impact, but also what we can do, the individual decisions we can make as physicians and how we can advocate for our patients to slowly hopefully lead to improvements.

Jeffrey G. Demain, MD, FAAAAI 48:59

Yeah.

Rebecca Saff, MD, PhD, FAAAAI 49:00

I just wanted to ask if there's other things that um you want to take people to take home as we think about climate change.

Jeffrey G. Demain, MD, FAAAAI 49:08

Well, I I I think well well, climate change is not coming. Climate change is clearly here and it's accelerating faster than any modeling done in the 1990s. Uh the you know, so significantly faster. Uh, like I said, what was anticipated 600 at 21 and 2100 will now occur probably before 2050. So that's pretty fast. The temperature is rising at an accelerated rate as well. So this is real. It's not something that you know we can just sit back and and do nothing. Uh I know it as individuals we're not quite powerless, but close. I think the greatest power we have is our voice, uh, and it's really important. Uh, you know, if we stopped all fossil fuel burning today, uh it's kind of said that we wouldn't be able to start turning the ship until uh maybe a hundred years from now. And I don't know how true that is, but we've got to start turning the ship sometime. So I think you know this is important and it should be focal. And as allergist, immunologists, we own that's our that's our that's our own that's what we own. We own the environment. I mean, we know the environment, we know how the environment interfaces with with our disorders that we take care of, and we should be there as advocates for let's make a change, advocates for education. Uh, we've got to kind of teach our patients and continue working. Uh so I think our voice is the most important thing we have. But I also feel like anytime we can, we should we should walk the talk. I really do. I think you know we should take it upon ourselves to make whatever changes we can. So I guess that would be my my final message.

Rebecca Saff, MD, PhD, FAAAAI 51:06

I'd like to work most days, so I try my try my best to to uh contribute in that small way.

Jeffrey G. Demain, MD, FAAAAI 51:12

Right. And you're in a beautiful situation. I mean, you you're training fellows. So, you know, you know that would be, I mean, I think that would be a very interesting component uh to fellowship is really understanding how these changes are occurring. Uh so there's a there's a book if um if I would recommend it's called The Greenhouse Planet. Uh it's written by Louis Ziska. Uh it's really a good book.

Rebecca Saff, MD, PhD, FAAAAI 51:41

Louis Ziska has done some of you know you talked about the groundbreaking research on you know the impact of climate change on plants, on radweed levels, on the effect of heat on plant production.

Jeffrey G. Demain, MD, FAAAAI 51:52

Yep. He has, he's a botanist, but he has done he did landmark papers, really. And and now unfortunately, he doesn't have um he doesn't have any grants. So, yes, uh a book that I really would highly recommend. And it's a very good read. It's called The Greenhouse Planet by Lewis Sisko. He's uh a PhD botanist that has done some tremendous work in this area looking at climate change and how it impacts atopic disease. He's spoken at our academy meetings, he did a plenary last year. Very nice man. Uh, he's now at um at Columbia, but I would really recommend that book. I read it on Kindle, and when I finished it, I ordered it uh in paperback so I could tag so it's a good read, and it's got a tremendous amount of meat to it. So there's my there's my final recommendation.

Rebecca Saff, MD, PhD, FAAAAI 52:49

Thank you. That's wonderful. Well, thank you so much for being here today and for sharing um all your knowledge on climate change, or at least some of your knowledge on climate change with us. I think we could probably do many episodes on climate change and its impact.

Jeffrey G. Demain, MD, FAAAAI 53:01

I think we could. Well, I really appreciate the opportunity. I do. This was I enjoyed talking with you, and I appreciate your recognition of how important this is in our specialty.

Rebecca Saff, MD, PhD, FAAAAI 53:14

We hope you enjoyed listening to today's episode. Please visit aaaai.org for show notes and any pertinent links from today's conversation. As a reminder, this podcast is not intended to provide any individual medical advice to our listeners. We do hope that our conversations provide evidence-based information. Any questions pertaining to one's own health should always be discussed with their personal physician. The Find an Allergist or attendant on the Academy website is a useful tool to locate a listing of board certified allergists in your area. Use of this audio program is subject to the American Academy of Allergy, Asthma and Immunology terms of use of climate, which you can find aaaai.org. If you'd like to show, please take a moment to write and subscribe to wherever you download your podcast. Thank you again for listening.