Climate change is threatening access to cancer care

After a natural disaster, the danger is far from over for residents with health concerns, whether cancer or other conditions. An extreme event may disrupt access to shelter, food, and water while also destroying medications, health supplies, roads, and health care facilities. Because power and telecommunications are often knocked out, telehealth can be difficult or impossible.

Extreme events are not new hazards. With a hotter planet fueling stronger and more unpredictable storms, flooding, wildfires, and heatwaves, however, researchers are having to rethink how they approach disaster preparedness and response and risk communication for increasingly vulnerable communities. “The same people who are at risk of flooding also may live in a fenceline community where the flooding could cause the redistribution of chemical contaminants that could also impact their health,” says Jennifer Horney, PhD, a professor of epidemiology at the University of Delaware in Newark.

That dual risk was laid bare by the 2017 flooding of the heavily industrialized Houston Ship Canal and surrounding neighborhoods by Hurricane Harvey, says Dr Horney, a core faculty member of the University of Delaware’s Disaster Research Center. Access, safety concerns, and other pressure points can likewise be magnified by extreme events. “If you have housing that’s not safe or a lack of transportation, those things are really important in non-disaster times to your health, but they’re really, really important in disaster times,” Dr Horney says.

For patients with cancer, the need for specialized care can compound the threat. “When you think about it in the context of access to care and extreme weather events disrupting that access, access to cancer care is really critical,” says Eva Rawlings Parker, MD, assistant professor of dermatology at Vanderbilt University Medical Center in Nashville, Tennessee. “It’s one thing if you miss your routine physical and can reschedule that. It’s quite another thing if you miss your chemotherapy infusion: It can have much more significant consequences.”

A 2019 study led by researchers at the American Cancer Society found that hurricane disasters were associated with worse overall survival for patients with locally advanced non–small cell lung cancer who were undergoing daily radiotherapy.¹ The longer the disaster declaration was, the worse their survival was, for disasters lasting up to a month. Because even short radiotherapy delays can decrease lung cancer survival rates, the authors recommended that disaster mitigation planning include strategies for identifying at-risk patients with cancer, arranging for their transfer to other treatment centers, and eliminating out-of-network insurance charges.

The growing urgency to develop contingency plans could be aided by lessons learned from vulnerable facilities and populations, notes Leticia Nogueira, PhD, MPH, scientific director of health services research at the American Cancer Society and lead author of the lung cancer radiotherapy study. After Tropical Storm Allison in 2001 inundated the tunnels connecting buildings in Houston’s Texas Medical Center, for instance, workers installed a submarine door system that allowed the complex to remain open during Hurricane Harvey.

After Hurricane Katrina in 2005 severely disrupted dialysis treatments for patients with chronic kidney disease, facilities in Florida worked together in the lead-up to Hurricane Ian in 2022 to avoid a repeat. The facilities offered dialysis the day before the storm’s projected landfall, strategically positioned water needed for dialysis treatments, and prioritized communication about which facilities had been affected by the hurricane and which were still open. Even so, dialysis inaccessibility contributed to at least three deaths.

Sharing lessons learned will be increasingly important as extreme events expand the range of affected populations. The East Coast, for instance, was largely unprepared to deal with widespread exposure from the Canadian wildfire smoke that blanketed major cities in 2023 and led to a spike in asthma-associated emergency department visits.²

In Lahaina, Hawaii, investigators are trying to determine how much contamination was released into the soil by the devastating wildfire and where it is safe to rebuild. “If you’re undergoing chemotherapy, your immune system will probably be weaker,” says Dr Nogueira. Such patients will be even more sensitive to pollutants deposited in charred soil or floodwaters, to mold in flood-damaged homes, or to contaminants in shoddily constructed temporary housing.

A disaster can also disrupt care from afar by, for example, breaking the supply chain for essential cancer care products. When Hurricane Maria hit Puerto Rico in 2017, it knocked out one of the main manufacturers of smaller intravenous bags used for children and thus created a serious shortage that affected pediatric cancer care throughout the United States.

In a disaster’s aftermath, transportation infrastructure provides the “backbone” for accessing critical needs, says Shangjia Dong, PhD, an assistant professor of civil and environmental engineering at the University of Delaware. The loss of an individual health care facility can affect its patients, but the loss of a transportation network—due to widespread and persistent flooding, for example—can create far bigger access problems at a regional scale.

The problem is particularly acute for Delaware, the lowest-lying state in the United States. In collaboration with agencies such as the Delaware Department of Transportation, Dr Dong and his colleagues are helping to assess which roads should be prioritized for projects to shore up vital transportation corridors. Instead of adding a few more minutes of travel time, the loss of some corridors could “become a life and death problem,” Dr Dong says.

In the same way, he says, floodplain maps should guide decisions on where to locate health care facilities and other critical infrastructure so that they will be operational and accessible when needed most. “It’s not ‘critical’ anymore if it cannot provide the critical services at a time of need,” Dr Dong says.

Interdisciplinary collaborations with Dr Horney and other health care experts have helped Dr Dong to understand the additional barriers layered onto engineering considerations, especially for highly specialized care. Beyond the difficult switch to a new care team if a hospital or clinic becomes inaccessible, regional alternatives may not provide the desired type of care or care that is covered by a patient’s health care insurance. “I think that’s when the intersection of infrastructure, resilience, and disaster science comes into play,” Dr Dong says.

For researchers studying the health impacts of climate change, Dr Horney says that better data and data sharing are among the biggest needs. Multiple federal agencies have taken notice and are ramping up their efforts to fund and promote data collection and dissemination. In 2022, underscoring the growing concern, the National Cancer Institute named climate change and cancer as one of six priority areas for research funding.

“From our perspective, there hasn’t been a lot of work in the area of climate change and cancer at any point, like risk, survivorship, or health care delivery issues,” says Curt DellaValle, PhD, MPH, a program director in the National Cancer Institute’s Division of Cancer Control and Population Sciences. The initial goal, Dr DellaValle says, is to raise awareness about new funding opportunities, help to grow the fledgling research area, and foster potential collaborations.

Some new efforts are trying to address multiple problems at once. The Centers for Medicare & Medicaid Services, for instance, recently approved microgrids as emergency power sources at medical centers. The microgrids can be used instead of generators that are reliant on diesel deliveries, which are often undermined by blocked roads. Diesel-powered emergency generators also expose surrounding communities to additional air pollution and contribute to the greenhouse gas emissions helping to fuel more powerful storms. “There are a lot of these solutions that are both climate adaptation because you’re not being impacted as much when there is a disruption, and also climate mitigation because you’re not contributing to the problem as much,” Dr Nogueira says.

She and other researchers also emphasize the importance of engaging at-risk communities in data collection and the search for solutions. “There’s a lot of local knowledge which has tended to be undervalued,” Dr Horney says, such as how heat waves and flooding have changed over time. Communities may already have the wisdom to be resilient, just not the resources. With a new emphasis on minimizing risk, whether for cancer or for other health conditions, more resources may help to reduce the undue burden of communities on the front lines of a warming planet.