Tackling the Massive Threat of Climate Change

By Stephanie Maximous, MD, MS
March 5, 2024

Soon after moving to Pittsburgh for my pulmonary and critical care medicine fellowship in 2014, I began noticing a theme: So many of my patients expressed a sense that the air they breathed was harming them or was in some way responsible for the severity of their lung disease.

In this city, the legacy of the steel industry from the last century fostered economic prosperity but resulted in a profound legacy of pollution as well. Unfortunately, due to a combination of fossil fuel dependence for electricity generation and transportation, industrial particulate matter (PM) generation and greenhouse gas emissions, temperature inversions related to the topography of the region, and, most recently, smoke from Canadian wildfires in the summer of 2023, the air quality in Pittsburgh ranks among the 25 least healthy US cities. Our patients are bearing the burden of climate change.

My patients relay that because of the poor air quality in the neighborhood they live in, they feel sick. I remember a patient in clinic talking about how on the days he could see a film of particulate on all the cars and the street outside, he knew he would feel more shortness of breath. Patients share about how when they had lived in different neighborhoods in town or traveled outside of Pittsburgh, their breathing improved.

Patients tell me that their asthma or COPD that did not use to cause them frequent trouble is now less well controlled despite better therapies available. Patients who used to experience seasonal allergies in just the fall or the spring now are plagued by their allergy symptoms year-round because of a warming climate yielding excess pollen throughout all seasons.

A recent study of patients with pulmonary fibrosis demonstrated that exposure to excess PM_2.5 in this region resulted in more rapid clinical deterioration and premature death compared with patients with the same disease in other parts of North America with better air quality. The common denominator is human-generated climate change’s negative impact on health.

In particular, those who are already vulnerable because of underlying chronic disease or socioeconomic disparity are at greater risk and feel these repercussions disproportionately. Black and brown communities are more heavily exposed to air pollution due to the history of redlining and ongoing structural racism and, as a result, have worse health outcomes than other groups. There is an urgency and moral imperative for us as clinicians to address generations of environmental injustice.

While these themes floated around in the background during the early stage of my career as a pulmonologist, I didn’t have language or deep knowledge around these structural environmental issues. As a profession, we are gradually recognizing that the health impacts of climate change on which to advocate are within our wheelhouse as clinicians.

Our patients and our trainees are increasingly aware of these issues, and, as a result, we as currently practicing clinicians and educators must urgently learn about the lived experiences of our patients and how their diseases interplay with their exposures.

Nowadays, I think more about how to mitigate the impact of air pollution, which did not previously factor into my training or the early years of my clinical practice. We know that some patients, particularly those with underlying lung disease and young children, are at greater risk when exposed to more polluted air and may need to take different steps to limit their exposure. We now consider advising these patients with chronic respiratory disease to be aware of air quality advisories and limit their time outdoors on worse air quality days. We anticipate that when the air quality is worse, we will see more complications of cardiovascular and pulmonary disease.

As lifelong learners, we thirst for the latest data to incorporate into our clinical decision-making. Similarly, colleagues and I are now also voraciously reading and starting to have conversations with peers about the convergence of climate change and disease.

The irony of our health care system is that though we care for patients whose diseases are exacerbated by climate change, health care itself has an outsized impact, estimated to account for 5% of all greenhouse gas emissions worldwide. As clinicians, our goal is to improve the health of our patients and communities, but the systems we work in simultaneously impart harm as well. From reliance on fossil fuel combustion for energy generation to large volumes of plastic and food waste, the climate footprint of our medical institutions is massive.

Sometimes the scope of the problem feels too overwhelming… Where can we even begin?

As a pulmonologist and intensivist, I begin with noticing opportunities to lessen my climate footprint at the bedside. In the ICU, we generate a tremendous amount of waste, much of which may be necessary for patient care; however, there may be alternatives with a smaller carbon impact, such as prioritizing reusable equipment like bronchoscopes and laryngoscopes over single-use disposable versions. I prompt our trainees to reassess the need for “daily” labs and “routine” imaging that may not be necessary or where the frequency could at least be spaced. In the ICU, we often spend tremendous resources on patients in their final days and weeks of life. Ensuring that we are prioritizing patient and family values and minimizing low-value care is integral to the quality of the work we do and also has a sustainability benefit.

It may not seem like clinicians have any bearing on a health care system’s supply chain, energy generation, or HVAC usage, but many hospitals are creating interdisciplinary sustainability teams that benefit from the voice and perspective of a bedside provider while allowing us to advocate for less reliance on fossil fuel energy sources, more sustainable supply procurement, and limiting wasteful HVAC practices where possible.

Finally, one of the most dramatic lessons I have been learning as a pulmonologist revolves around the environmental impact of one of our most frequently prescribed therapies: hydrofluoroalkane (HFA) aerosol metered-dose inhalers (MDIs). The HFA propellants in MDIs that we use most commonly for asthma and COPD management yield tremendous greenhouse gas emissions, by some estimates comparable with the carbon footprint of all hospital staff transportation emissions for commuting to work. While not appropriate for every patient subpopulation—such as young children or patients with severe chronic lung disease that results in impaired inspiratory force—dry powder inhalers (DPIs) and soft mist inhalers (SMIs) are alternative aerosolized medication delivery mechanisms with much smaller global warming potential.

As prescribers, we can prioritize DPI and SMI formulations for many of our adult patients, and we can engage our health care system’s pharmacists, health plan administrators, and other medication formulary stakeholders to incorporate considerations around environmental impact into drug preference and coverage. Even more importantly, optimizing underlying disease control by confirming correct technique of inhaler devices, use of a spacer, and ensuring that patients have access to affordable combination inhaled medications in accordance with the most updated asthma and COPD guidelines can result in less reliance on use of their “rescue inhaler”—commonly a short-acting beta agonist such as albuterol in HFA MDI formulation.

Finally, as a profession, we can advocate for pharmaceutical companies to urgently bring low emissions inhaler devices to the market and ensure their affordable access in order to provide more alternatives, particularly for those who are not candidates for current DPIs or SMIs.

No matter how compelling and urgent these issues are, one clinician cannot tackle the massive threat of climate change and complexity of health care sustainability in isolation. I am fortunate to work with several like-minded and highly motivated colleagues at my own institution. We have been able to organize effectively—through initiatives like Clinicians for Climate Action—to spark local change toward reducing our system’s carbon emissions.

Similarly, through professional organizations like CHEST, I have been able to collaborate with other pulmonary and critical care clinicians who share these passions and are doing similar advocacy work across the country. Organizations like Health Care Without Harm, Practice Greenhealth, the Global Consortium on Climate and Health Education, and the Medical Society Consortium on Climate and Health, among others, are groups and networks facilitating this work, providing resources, and supporting clinicians to organize and engage on these critical fronts. I am honored to serve as CHEST’s representative to the Medical Society Consortium on Climate and Health as another avenue to keep advancing this cause at scale in collaboration with advocates across all specialties.

While I worry every day for my patients, our communities, and my children as we face the accelerating threat of climate change, knowing that I am actively engaging in these efforts in pursuit of environmental justice and mitigating health care’s climate change contribution gives me a sense of empowerment and solidarity with others also striving to lessen our burden on the planet.