Dr. Shannon Westin, Dr. Abbas M. Hassan, and Dr. Leticia Nogueira discuss the impact of heatwaves on cancer care delivery and what can be done about it.

TRANSCRIPT

The guests on this podcast episode have no disclosures to declare.

Dr. Shannon Westin: Hello, everyone, and welcome to another episode of JCO After Hours, the podcast where we get in-depth on manuscripts that are published in the Journal of Clinical Oncology. I am your host, Shannon Westin, GYN Oncologist and Social Media Editor for the Journal of Clinical Oncology. I'm so excited to be here today to discuss a very thought-provoking manuscript. This was published on June 10, 2023, in the Comments and Controversies section of JCO, and it's entitled "Impact of Heatwaves on Cancer Care Delivery: Potential Mechanisms, Health Equity Concerns, and Adaptation Strategies."

And I am thrilled to tell you I am joined today by two of the authors of this very important manuscript. Dr. Abbas Hassan is an intern in the Division of Plastic Surgery, Indiana University School of Medicine. Already reaching for the stars, publishing in the JCO as an intern, that has to be a record. Congratulations and welcome, Dr. Hassan.

Dr. Abbas Hassan: Thank you for having us. Appreciate it.

Dr. Shannon Westin: And with Dr. Hassan is Dr. Leticia Nogueira. She is now the Scientific Director of Health Services Research at the American Cancer Society. Welcome, Dr. Nogueira. I'm so excited to have you.

Dr. Leticia Nogueira: Excited to be here.

Dr. Shannon Westin: Let's get right to it. This topic is very timely. We are currently enjoying several weeks of greater-than-100° weather here in Texas, where I am, and across the United States. Why don't we start by just defining heatwaves in general and what their global impact is on morbidity and mortality?

Dr. Abbas Hassan: Yeah. So, I mean, it's the Texas heat, right? It's hard to ignore it when you're sweating buckets, right? So this kind of extreme heat isn't just a Texas problem. It's happening everywhere, so from Australia to Europe and across the US. And what we're experiencing, my friends, are heatwaves. They're like the unwanted guests at a barbecue, showing up uninvited, hanging around for at least two straight days. Now, defining a heatwave isn't straightforward as it might sound, with various different definitions across studies and policies. But one thing that is clear: heatwaves aren't just about discomfort. They're deadly. They're claiming more than 5 million lives globally every year.

Now, let's just imagine for a moment the year 2020. Not exactly a walk in the park. And on top of that, everything else, heatwaves cost over $4.5 billion in damages in the US. And that's probably just the tip of the melting iceberg, considering the tricky task of identifying exact heatwave periods.

Dr. Shannon Westin: And you said it's really hard to define, so I imagine that that makes it really difficult to study. Hopefully, I think we've already gotten our first call to action is coming up with some type of consistent definition so we can truly look at this in a scientific fashion. I guess I'm asking you to predict, but I'll do it anyway. What do we expect to happen over the next 30 years in regards to the climate change we're seeing and maybe overall temperatures across the globe?

Dr. Abbas Hassan: The way things are going, we're probably going to need a lot more sunscreen and a lot more ice cream. In all seriousness, the outlook is pretty stark. By 2023, we're looking at 8.1 million of our fellow Americans facing temperatures hotter than 125°F. And fast-forward to 2053, the number skyrockets to like 100 million. So that's a 13-fold increase. Remember when we thought 2014 was hot? And then 2015 came in, then 2016, and now all the way to 2020. Each year seemed to outdo the last, making the past seven-year span the warmest we've ever experienced. So we're not just dealing with a few off years. We're in the midst of a trend that's heating up our planet and impacting our health at an alarming rate.

Dr. Leticia Nogueira: Yes, I would like to add to that, exactly what Dr. Hassan said. We don't really need to worry about or focus on what temperatures are going to be in 30 years. It is here now. The threats of climate change are here now, threats of extreme heat, no matter how we define it, right? Because it could be number of days above a certain temperature threshold, and that threshold is usually established by the previous 30 years. And we've already seen these jumps in temperatures in the previous 30 years, especially in most recent years. So these hazards, these threats, are already here. No future projections necessary to understand the hazards and the detrimental consequences of exposure to extreme heat due to climate change.

Dr. Shannon Westin: Well, let's talk a little bit about that. And specifically, I would love to hear kind of what we've been seeing as far as the impact of heatwaves on health outcomes. I think our group would be interested in knowing, what are some of the things that you're seeing and you're experiencing? And then further, what are the things that make people more vulnerable, let's say, to the climate hazards?

Dr. Abbas Hassan: Yeah, let's dive in a bit more into what makes us vulnerable to these heatwaves. When you think about vulnerability, the key elements are, one, increased exposure; two, increased sensitivity; and three, decreased ability to adapt. So think about it this way: Let's say you're—not sure if you guys play this—let's say you're playing a game of tag, and the sun is it. Now the sun is pretty good at tag, so anyone spending a lot of time outside—that's increased exposure—is more likely to get tagged. Then you have some players who are, for various reasons, they're slower or less agile. So this can be due to age, health conditions, or other factors that make them more sensitive to heat. They're not able to dodge the sun as quickly. So that's increased sensitivity. And finally, imagine some players are dressed up in heavy clothing, unable to change into something cooler. They don't have the resources to adapt. So that represents that decreased adaptive capacity. While everyone playing this game can feel the burn, there are some who are more at risk.

So, for example, individuals with cancer are particularly at risk because they have various physical, psychological, socioeconomical consequences of their diagnosis, treatment, and even their path to survivorship. And this can include everything from weight loss to tumor, compromised immunity, side-effects from medications, and even financial stressors, making their game of sun tag especially challenging. So when we talk about the impact of heatwaves on health, it's not a one-size-fits-all issue. Our vulnerability is a complex combination of various factors that can leave some of us more at risk than others. And it's this understanding that can help shape our approach to tackling the challenges that climate change brings.

Dr. Shannon Westin: That was very well stated, and I think I want to dig in a little bit deeper on some of the broad factors you covered, especially as it relates to patients with cancer, who obviously fit in the category of vulnerable to really all those pieces. So I'd love to dig in a little deeper. So let's talk a little bit more about age. I know that certainly patients with cancer can be any age, but it does seem to affect patients that are older or more elderly. How might that impact sensitivity to these heatwaves?

Dr. Abbas Hassan: Okay, so dig a little deeper here. The reality is that getting older comes with its fair share of challenges, and one of them is increased sensitivity to heat. So as we age, we become more susceptible to heat. And this is particularly true for individuals over the age of 65, many of whom are also dealing with a cancer diagnosis. In fact, the number of seniors with cancer is expected to nearly double by 2060. So heat sensitivity in this group is due to several factors. First, our body's ability to regulate heat, or thermoregulation, declines with age, much more like an old car cooling system not working as it once did. So this means we're less able to handle extreme heat, making us more vulnerable during heatwaves. And this vulnerability is especially concerning for older cancer patients because some cancer treatments can cause additional complications, such as kidney injury, which can impair our cooling systems even further.

Additionally, these treatments can lead to dangerously high levels of hypernatremia and hyperkalemia, and this can lead to serious complications like cardiac arrhythmias. So in other words, the aging process coupled with cancer and its treatment can make older folks more susceptible to the harsh impacts of heatwaves.

Dr. Shannon Westin: That makes sense. So you started to touch a little bit on comorbidities with discussing heart disease and arrhythmias and how that might impact. Are there other comorbidities that are certainly quite common in patients with cancer that can impact health conditions related to climate change?

Dr. Leticia Nogueira: Yes. So, in addition to, as Dr. Hassan mentioned, some chemotherapy drugs inhibiting thermoregulation makes it harder for people to control their body temperature, several cancer treatments also impact kidney function, and kidneys are important organs for body temperature regulation. Even some cancer treatment drugs also lead to cognitive impairment, which makes it harder to recognize heat stress and heatstroke symptoms. It could also impair mobility and the ability to go look for a cooling, safe space. There are several other cardiorespiratory comorbidities that can also impact sensitivity to extreme heat. And we cannot forget that cancer diagnosis treatment comes with socioeconomic consequences as well, because it impacts the ability of individuals to remain employed or maintain the same level of income. And these socioeconomic consequences also impact the adaptive capacity that Dr. Hassan was mentioning, such as installing air conditioning or improving insulation during a heatwave or throughout the year, which makes individuals diagnosed with cancer more vulnerable to these threats.

Dr. Shannon Westin: You had mentioned some of the economic challenges here. I'd love to speak a little bit more about that, and I think we certainly see this in vulnerable populations just in general, being able to receive their cancer treatment or make it on time for their treatments. In addition to that, are there limitations around accessing resources or things that would help protect people during these heatwaves?

Dr. Leticia Nogueira: Yes, we see a lot of barriers in access to resources in communities that have been targeted for marginalization or they are experiencing barriers in access to resources. Right? We can start with some of the ways that our urban centers are built. Concrete and asphalt trap heat in urban centers, leading to this effect called the urban heat island. So you see almost a 20° difference between urban centers and more suburban or rural areas when it comes to these hot days. And that, of course, increases exposure to extreme heat, which is one of the components of vulnerability.

Then you have sensitivity. If there are barriers in access to healthy resources, healthy foods, places to exercise, and there are, for example, an increase in targeted advertising for tobacco or alcohol outlets in the neighborhood, that has been shown to be associated with an increased prevalence of several chronic health conditions. And as we were discussing, these chronic health conditions also increase sensitivity to climate hazards.

And then, of course, there is adaptive capacity. We were mentioning the challenges faced by people who have been diagnosed with cancer in being able to afford some of the infrastructural updates that are necessary to cope with extreme heat. And the same challenges apply for people who are experiencing other types of socioeconomic distress, making it harder for these communities to prepare and respond to the challenge posed by heatwaves.

Oh, there's one more thing. I just wanted to mention that this is a concern, the adaptive capacity, not only for these communities that are facing barriers in access to resources. With climate change, there's been an increase in power outages. So, even if you can afford to use AC, it does not mean you're going to be able to use it during a heatwave because these power outages are becoming more frequent, especially as people turn up their AC and overwhelm the electric grid. So this is a concern for all US residents, not just people from lower socioeconomic levels or cancer patients.

Dr. Shannon Westin: You are speaking my language, coming from Texas, where our grid is a constant source of--

Dr. Leticia Nogueira: I lived in Texas for a while. Yes.

Dr. Shannon Westin: I know you did. I saw that in your bio. Okay, well, I think we got the scope. I'm appreciative of the level of detail that you all were able to cover in such a short period of time. So I think now let's move towards the kind of action items, like what can we do? How can we mitigate some of these issues, or all of these issues? Start wherever you think your lowest hanging fruit is, I would say.

Dr. Abbas Hassan: Okay, absolutely. So addressing the challenges that climate change presents, especially for vulnerable groups like cancer patients, is, I would say, a lot more like putting together a jigsaw puzzle. It requires us to work on multiple fronts at once and fit all the pieces together to form a complete picture. So let's walk through this puzzle together. So picture this: Our first puzzle piece involves upgrading our healthcare infrastructure. We need to gear up our systems with surveillance, monitoring, and even staffing to swiftly detect and respond to heatwaves. The second part of the puzzle is that our healthcare workers, or providers, need to become more aware of climate change. They need to provide guidance to their patients that suits their cultural context and language, discussing things like what they need to wear during a heatwave, the best way to travel, even what changes to make in their diet. But how would our healthcare providers turn into these warriors? Well, that brings us to our next piece, like continuing medical education. So, by providing education opportunities into medical and public health curriculums, we can create a force of well-prepared healthcare providers and professionals ready to fight the challenges of climate change.

And also considering how heatwaves can affect our medications. As temperatures rise, we need to think about developing thermostatic medications that can withstand the hotter conditions. It's like equipping our medications with their own little heat shields. Lastly, I think, which is perhaps most importantly, we need to be stewards of our own environment with our own healthcare systems. This includes reducing our carbon footprint and advocating for heat equity. So a concept that ensures that everyone, irrespective of their socioeconomic status, has access to and protection from heatwaves' related risks. So, just like that jigsaw puzzle, every piece plays a crucial role. By working on those front lines simultaneously, we can build a more resilient, equitable healthcare system ready to face the rising temperatures.

Dr. Shannon Westin: Okay, you absolutely win on JCO After Hours for the best examples. The puzzle pieces. I'm just—I am, like, obsessed. This was—you're amazing.

Dr. Leticia Nogueira: Playing tag, right? He's a natural.

Dr. Shannon Westin: Playing tag, the sun exposure. I was like, this is like… I have to say you are very well suited for this type of work.

Dr. Abbas Hassan: You're too kind. Thank you.

Dr. Shannon Westin: And honestly, I think when you put it like that—sometimes these kind of problems seem so big and overwhelming, but when you kind of break it down into those chunks, it does seem doable. And I think almost every time on this podcast I bring this up, but I'm going to do it again. What can we do to change policy, right? We need a policy change. Like, some of what you mentioned is medical education, things like that. But really, what about lawmakers? What do we need to be talking to our lawmakers about so that we can get broad-based policy changes that will help us enact some of these strategies that you just so well described?

Dr. Leticia Nogueira: I also wanted to add something I think is relevant to both here, and that is that the United States healthcare system is the second largest industry when it comes to emissions in the US. Emissions from the US healthcare system alone surpass emissions from the entire United Kingdom. So there is a big component of this strategy here to recognize that it is anthropogenic, manmade emissions that are causing climate change and leading to these detrimental health consequences. In our role, there are only so many Band-Aids we can put on this side before we start evaluating how we're actually contributing to the problem.

And here is where this jigsaw puzzle and the policy and "I'm getting overwhelmed" kind of all comes together because there are several different efforts that are both climate mitigating and also improve climate adaptation. For example, switching towards clean energy sources that are generated on-site at healthcare systems can decrease the emissions of these institutions and also make them more resilient to power outages that, as we talked about, are only becoming more frequent. And there are several other examples. And you were asking about policy. I think that one of the recent advances when it comes to policy-level interventions comes from the Inflation Reduction Act, where we have a lot of incentives for shifting towards more clean energy sources and decreasing our environmental impact with our professional activities that we need to keep in mind as we're trying to protect the health and safety of cancer patients.

Dr. Shannon Westin: Great. Thank you so much. And I guess that we're getting towards the end of this. It's gone by very fast, and I personally am writing down my to-do list of things I need to do tomorrow. What is next for you all for your work in this space?

Dr. Leticia Nogueira: I think that, as a researcher, there's a few different things that we can do. Similarly, as you are a clinician or a psychooncology or any of these other professions. One of them goes back to Dr. Hassan was saying surveillance and measuring the effects because that increases awareness and provides the background evidence that's necessary for developing and implementing solutions, right?

And then, of course, being champions within our own institutions so that we are both trying to solve the problem when it comes to protecting the health and safety of patients. Is it possible to use electronic health records to identify those who are most vulnerable? Can we expand on data sharing and information sharing so we can build on lessons learned from previous heatwaves and do better next time? And then how, of course, can we contribute to reducing the emissions from our own institutions so we stop contributing to the problem we're trying to solve?

Dr. Shannon Westin: Well, this was so educational, and I am so pleased that we had an opportunity to talk to you about this really important paper. I just want to thank, again, Dr. Hassan and Dr. Nogueira for taking the time to review this and really for thinking through this very important problem. And I hope it inspires all of you to look at what your institutions are doing and determine what strategies you might be able to utilize to start to mitigate some of these problems.

Again, we were discussing the Comments and Controversies manuscript "Impact of Heatwaves on Cancer Care Delivery: Potential Mechanisms, Health Equity Concerns, and Adaptation Strategies," which was published in the Journal of Clinical Oncology June 10, 2023. If you haven't read it, run, don't walk, to do so. And please do check out our other JCO After Hours podcasts on our website. And if you have any problems, reach out to me on Twitter. I'd love to chat. Have a great day.

The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.

Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.

Impact of Heatwaves on the Care of Patients With Cancer

Journal of Clinical Oncology (JCO) Podcast

Impact of Heatwaves on the Care of Patients With Cancer