The Climate Emergency and the Health of Our Patients: The Role of the Rheumatologist

The Climate Crisis represents an emerging threat to the health of humanity and to the health of our planet. Since the dawn of the Industrial Era the average air temperature has risen by about 1 degree Celsius, due mainly to human-caused emissions of greenhouse gases (GHG) related to the use of fossil fuels. The link between warming temperatures and GHG production was first described in 1896 and was confirmed by the measurement of rising atmospheric CO2 in the late 1950’s (1). Despite years of accumulating scientific evidence, and the stated objectives of the United Nations Framework Convention on Climate Change, a concerted global effort to slow and decrease GHG production has lagged (3). We are now faced with the consequences of this inaction where what we referred to as the Climate Crisis has now become a Climate Emergency (2,3). Rising temperatures have led to more extreme weather events and negative health impacts, which include more frequent and severe heat waves, more wildfires with greater particulate matter (PM) exposure, more allergies and asthma due to longer pollen seasons, a greater range and impact of vector-borne and other infectious diseases, and warmer oceans and rising sea levels leading to more severe storms (2,4). These changes, along with worsening droughts and flooding, can lead to food insecurity, population displacement, increased psychological stress and mental health disorders and civil unrest. As health care professionals and as rheumatologists, specifically, we must understand that emerging effects of this Climate Emergency represent a public health crisis that will affect the health of our patients. Thus, we must prepare ourselves and our patients with rheumatic disease to adapt to our changing environment. As concerned physicians and researchers, we believe that all rheumatologists, with the support of the American College of Rheumatology (ACR) must confront the reality of the Climate Emergency, and act on behalf of our patients’ health and well-being now and for the future.

How can the Climate Emergency affect the health of our patients?

The effects of climate change on patients with rheumatic disease have not yet been rigorously investigated. Data from other disciplines of medicine such as allergy, pulmonary medicine, nephrology, and cardiovascular medicine clearly show the significant impact of climate-related factors on disease exacerbations (4). Similar mechanisms for these conditions likely apply to individuals with rheumatic diseases. For example, excessive heat exposure represents an important risk for morbidity and mortality, especially in urban environments in what are called heat islands. Many of our patients with systemic lupus erythematous (SLE), rheumatoid arthritis (RA) or vasculitis have systemic manifestations that include renal, pulmonary, and cardiovascular complications that may be exacerbated with heat exposure. Greater pollution exposure, and often co-existent allergic disorders due to longer pollen seasons, place our patients at risk for respiratory complications, especially in those with lung disorders related to their rheumatic disease (5). Our patients who are exposed to more expansive and severe wildfires may be at risk for small particulate matter (PM 2.5) exposure that can worsen morbidity in those with underlying respiratory and cardiac diseases, conditions common to patients with rheumatic diseases. Of particular concern are patients from groups that have been historically, economically and socially marginalized, and specifically, racial and ethnic minority groups that we know fare worse with their rheumatic diseases. Thus, the effects of climate change could serve as a force multiplier of morbidity amongst vulnerable groups with rheumatic diseases (6,7). It is imperative that we better understand which patients and communities are at highest risk for exposure to climate related effects so that adaptive strategies can be tailored to these specific populations to prevent further health disparities.

What is the role of the rheumatologist and the ACR?

Educate physicians and patients

There had been no known efforts made to educate our rheumatology workforce on this critical topic until the American College of Rheumatology (ACR) 2021 Convergence conference, which had an educational session and a newly formed Study Group focusing on Climate and Health, which were attended by over 200 participants. The discussion indicated that there was significant interest amongst rheumatology health professionals to better understand the health effects of climate change and to consider what research questions should be considered moving forward. Numerous medical societies have already undertaken this effort and there are now widely available resources through organizations such as the American College of Physicians and the Medical Society Consortium on Climate that offer patient and physician education. These issues should be integrated into our present ACR educational infrastructure, both online and in our ongoing in-person, virtual and hybrid conferences (7,8).

Engage in research on the effects of climate and the environment on the immune system and on rheumatic disease

Very little research is available that directly and comprehensively links environmental exposures, pollution, stress and other emerging climate threats with specific rheumatic diseases and with adverse effects on the immune system. A higher incidence of rheumatic disease was found among individuals with high dust cloud exposure at the site of the 9/11 attacks on the World Trade Center, raising the possibility that exposure to particulate matter and inhalation may play a role in autoimmunity (9). Populations exposed to industrial pollution, which include historically marginalized populations, and those exposed to repeated smoke and PM exposure due to wildfires, represent potential areas of epidemiologic study to assess the possible links between environmental exposures related to climate change and the development of autoimmunity. There are substantial data that suggest a relationship between pollution, PM exposure and SLE risk and disease activity (10,11). Inhalation has been postulated as a potential mechanism for the development of autoimmunity, and a recent analysis of a large cohort of RA patients suggested a relationship between recent PM exposure and the development of RA flares and elevated C-reactive protein (12). It is plausible that perturbations in our environment related to climate may lead to alterations of our immune system that may predispose to the development of autoimmune diseases, increase the likelihood of flares of disease or alter responses to therapy. Understanding the potential mechanisms of how these environmental exposures can cause such changes in the immune system will be challenging but may provide a co-benefit of offering novel insights into mechanisms of diseases that we still struggle to understand (13). The ACR, the Rheumatology Research Foundation, the National Institutes of Health, and other rheumatic disease-related foundations should encourage collaboration amongst investigators that lead to large-scale research efforts to better understand these mechanisms and to develop strategies to mitigate the effects of the Climate Emergency on our patients (14). A forthcoming White Paper, commissioned by the ACR, will delve deeper into the current state of the literature examining specific associations between environmental factors and rheumatic conditions.

Encourage sustainability in healthcare

Healthcare in the US accounts for over 8% of GHG emissions in the US and efforts to limit energy expenditure and waste have become a priority in many health care systems (8). These efforts apply to all healthcare activities, including inpatient, outpatient, and research laboratory settings. We call upon rheumatologists, alongside all medical professionals, and the ACR, to engage on the issue of sustainability in their own settings and work towards cutting waste and lowering our institutional energy and carbon expenditure. Such efforts offer the benefit of not only limiting waste and energy use but may offer cost savings as a co-benefit (8). For example, Healthcare without Harm is an organization that offers practical guidance and resources to help reduce the environmental burden of healthcare delivery.

Advocate for mitigative and adaptive strategies in dealing with the Climate Emergency

It is critical that rheumatologists advocate either on a local, national or global level to support public health policies that foster adaptative strategies to extreme weather events. Examples include targeted communication, education and emergency planning for patients living in urban heat islands or providing additional resources like access to cooling centers. Advocacy for mitigative strategies to speed our transition from carbon energy sources towards renewable energy will be critical to limit damage to our environment and the risks incurred to our patients.

While addressing the Climate Emergency represents a daunting task, there is hope moving forward. Renewable energy is quickly becoming more affordable and widely available and fossil fuel investments are losing value, making it easier to decarbonize our environment and limit the rise in global temperature, which we need to accomplish within the next decade based on goals set by the Paris Agreement and the Glasgow conference. With each challenge we face in the Climate Emergency, there are known solutions or resources that we can utilize right now in cost-effective ways and more will emerge going forward (15). Not engaging on this critical issue and standing with our colleagues across other fields of medicine would be a great disservice to our patients with rheumatic conditions who we know will be affected. Just as we faced the challenge of the COVID-19 pandemic, we will now need to adapt again and bring our skills and resources to act, this time through the lens of the Climate Emergency, for the sake of our patients and for the sake of our planet.