Protecting older adults from the effects of disasters and extreme weather

Weather and climate disasters are on the rise. In 2021, there were 20 extreme weather and climate events in the United States, triple the average number of events 15 years before. These extreme events included droughts, heat waves, wildfires, floods, tornadoes, and hurricanes. Research suggests that older adults are particularly vulnerable to the health effects of these disasters, but the specific reasons behind this susceptibility are still being explored.

As a part of a broader NIH-wide initiative, NIA funds research that explores the effects of extreme weather and natural disasters on older adults, with the ultimate aim of improving the well-being of people who experience these events.

“Older adults are particularly vulnerable during weather and climate disasters,” said Emerald Nguyen, Ph.D., an NIA program official. “There is a pressing need to explore their experiences and health outcomes during these events. NIA supports a wide range of research that aims to better understand how we might support older adults’ resilience, preparedness, and recovery from disasters.”

Disasters disrupt regular health care for older adults

While you may think that disaster response health care is all about treating burns, broken limbs, hypothermia, and other pressing medical emergencies, that’s only part of the story. When a community is affected by a disaster, the regular health care services that the community offers are affected, too. Sue Anne Bell, Ph.D., assistant professor at the University of Michigan School of Nursing, leads a team that studies how communities and health care systems can better support older adults through the phases of a disaster.

Bell, a nurse practitioner by training, regularly deploys to disasters across the country as a part of a federal disaster response team. She has extensive experience providing support in many different types of disaster, from hurricanes in Puerto Rico to California wildfires to the COVID-19 response.

In Bell’s experience, most of the care provided in the days and weeks after a disaster is basic primary care and management of chronic health conditions, such as diabetes, high blood pressure, cancer, and kidney disease. According to a report from the Centers for Disease Control and Prevention (CDC), approximately 85% of U.S. adults over age 65 have one or more chronic diseases. People with these conditions need, and benefit from, regular access to health care. When a disaster makes it difficult or impossible to get health care services, older adults with chronic diseases are affected more than others.

Using large sources of data, such as Medicare claims records and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) Program, Bell’s team discovered that disruption of basic health care has serious consequences. In an NIA-funded study, Bell and her colleagues found that people with breast cancer who lived through Hurricane Katrina in 2005 experienced interrupted care and were more likely to die within 10 years than those not exposed to the disaster. Bell’s research has also demonstrated that living through disasters, when regular health care services and access to treatment may be limited, increases the likelihood that older adults will be hospitalized. Moreover, older adults living in poverty and those with certain chronic conditions are more likely to be hospitalized during or immediately after a disaster compared to all older adults.

Bell and her team are investigating strategies to promote healthy aging in communities affected by disasters, including improving home-based care before and after a disaster. Home-based care describes health care services that are provided by a professional caregiver in a person’s home — the modern-day equivalent of a house call. Most older adults in the U.S. are aging in their own homes, rather than living in nursing homes or other care facilities. Preliminary findings from the NIA-funded study suggest that increasing access to home-based care could help fill the gaps in care that occur for older adults living at home during a disaster.

Additionally, NIA funds research into how large-scale organizational changes to primary care access could help meet the health needs of older adults during disasters. One study that began early in 2022 aims to identify which models of physician organization (such as federally funded health centers or independent medical groups) best meet people’s health care needs during Puerto Rico’s ongoing recovery from Hurricane Maria in 2017. Findings from the study may suggest how to prioritize the expansion of specific services that most directly improve the lives of older patients and their caregivers.

Some medications may make older adults more sensitive to heat

Many older adults take prescription drugs to manage chronic diseases and other health conditions. According to a report by the CDC, 83% of U.S. adults in their 60s and 70s had used at least one prescription drug in the previous 30 days and about one-third used five or more prescription drugs. Some medications increase heat sensitivity by interfering with body temperature regulation, suppressing thirst, or disrupting fluid balance. So, older adults who take medications to treat chronic diseases may be especially vulnerable to our changing climate, particularly extreme heat and heat waves.

Soko Setoguchi, M.D., Dr.PH., a professor of medicine and epidemiology at Rutgers Biomedical and Health Sciences, has been researching the health effects of climate change for more than 10 years. Her research examines the relationship between extreme heat and medication use in older adults. She has not only a professional interest, but also a personal one. “As a mother who cares about the future of the planet and the children, I believe we need to work harder toward understanding and mitigating the effects of climate change on health,” said Setoguchi.

During heat waves, older adults with certain chronic conditions are more likely to be hospitalized with heat-related conditions such as heat stroke and dehydration. Setoguchi’s research team examined whether taking certain medications makes older adults more likely to experience health problems during heat waves. The study, funded in part by NIA, examined data from almost 400,000 Medicare beneficiaries over age 65 with chronic conditions such as diabetes; dementia; and heart, lung, or kidney disease. The results showed that several classes of drugs (specifically ACE inhibitors, anticholinergic medications, antipsychotics, and loop diuretics) are associated with higher risk of heat-related hospitalizations for older adults with chronic conditions. The study did not find a meaningful difference between heat waves and other hot summer days.

Understanding how medications interact with heat can help older adults and health care providers make informed decisions to help lower risks. “For example,” said Setoguchi, “if we found that patients taking certain medications, such as diuretics, have a significantly higher risk for heat-related hospitalization, clinicians might advise patients to be aware of the risk and potentially adjust the dose of medications when exposure to extreme heat is expected.”

Setoguchi notes, however, that the decision to adjust medication is complex and must be made by patients guided by their health care providers. You should always talk to your doctor if you have concerns about medications you are taking.

Certain older adults are more resilient than others

Not all older adults who experience a natural disaster are affected the same way. Scientists are researching why certain older adults are able to cope with the effects of disaster while others are vulnerable. For example, Rachel A. Pruchno, Ph.D., director of research at the New Jersey Institute for Successful Aging, studies how disasters worsen the daily functioning of some older adults but not others.

Pruchno’s research was not originally disaster related. Her team started collecting data in 2006 as a part of the Ongoing Research on Aging in New Jersey: Bettering Opportunities for Wellness in Life (ORANJ BOWL) study. They were interested in factors that contribute to healthy aging generally, outside of the context of disaster. Six years later, Hurricane Sandy struck.

“Happenstance led me to become a disaster researcher,” said Pruchno.

When Hurricane Sandy hit the state, her staff had already collected three waves of data from more than 3,000 ORANJ BOWL participants. Pruchno felt that she had to switch her research focus, as she had been given a unique opportunity to understand how a hurricane affects the physical and mental health of older adults.

In an NIA-funded study, Pruchno’s team analyzed the data with particular attention to tasks of daily living, including walking up steps, kneeling, grasping small objects, and carrying heavy items. Pruchno and her colleagues compared older adults whose daily functioning worsened in the six years after the hurricane with older adults whose daily functioning was not affected. Overall, the data revealed that older adults with low incomes, low levels of social support, poor mental health, and poor physical health before the hurricane were the most likely to experience limitations in daily functioning after the disaster. These findings highlight the need to direct disaster preparedness and response resources to these groups.

Pruchno and her colleagues also found that having certain experiences during the disaster affected older adults’ daily functioning years later. Those who experienced traumatic stress during a storm, such as a difficult evacuation, were more likely to have limited daily functioning six years later. Pruchno’s team found this association for several specific skills, including walking up a flight of stairs, carrying a heavy bag of groceries, and standing for two hours without resting. According to Pruchno, focusing immediately after a disaster on helping older people who experienced traumatic stress may help alleviate these limitations before they develop. Additionally, understanding that not everyone who lives through a disaster has the same experiences may help researchers find meaningful associations between particular types of disaster exposure and health outcomes.

Neighbors can buffer the adverse impact of disaster

Having close social connections can help buffer the mental and emotional tolls of disasters. Ichiro Kawachi, Ph.D., professor of social epidemiology at Harvard T.H. Chan School of Public Health, leads a team that studies how relationships with family, friends, and neighbors can help older adults during a disaster.

In the NIA-funded Iwanuma Study, Kawachi and his team examined data from older survivors of the 2011 earthquake and tsunami in northeastern Japan. The study started as a collaboration between Kawachi and colleagues in Japan who had established a nationwide cohort to study the factors that contribute to healthy aging. As with ORANJ BOWL, the study was not originally intended to study the effects of disaster. 

“About seven months after we finished establishing the baseline surveys, the Great East Japan earthquake happened. It was pure chance,” said Kawachi. He soon realized that one of the field sites of the nationwide study was in the town of Iwanuma, about 50 miles west of the earthquake’s epicenter. Kawachi’s team had already collected data about older adults’ social relationships before the earthquake. Now they could examine how these connections influenced the impact of this disaster.

Kawachi and his colleagues studied more than 3,000 older adults who were profoundly affected by the disaster, defined as anyone who lost a loved one, had housing damage, lost a job or other source of economic stability, or had their medical care interrupted. The researchers found that those who were affected by the disaster in these ways experienced steeper cognitive decline and increased rates of post-traumatic stress disorder (PTSD) than those who were not affected by the disaster. The older adults who experienced the most severe consequences were those who lost their homes and were moved to temporary shelters, separating them from their friends, family, and neighbors. The researchers found that older adults who were able to maintain social connections, such as informal socializing with neighbors and family, were protected from some negative effects, such as symptoms of depression.

Based on Kawachi’s data, keeping social groups together during relocation may protect older adults from future health issues. When whole neighborhoods were relocated together (instead of as single households), older adults in those communities had lower rates of cognitive impairment and mental illness. Based on these findings, avoiding relocation to temporary shelters and trying to keep social units together may protect the health of older adults exposed to disaster.

Kawachi’s research with earthquake and tsunami survivors paves the way for the study of social connectedness as a protective factor in other types of disasters, such as the COVID-19 pandemic. Since the pandemic emerged in early 2020, it has disrupted social connectedness on an unprecedented scale throughout the world. Kawachi’s research suggests that this puts a lot of people at risk, especially older adults, and emphasizes the need to increase our understanding of how social connections influence health. In the future, Kawachi aims to find out “how we can recruit the strength of the community in order to meet these new challenges.”

Shaping research to inform disaster recovery practices

Insights from scientific research can be used to help federal and state governments respond more effectively to disasters. For example, these insights could lead to the development of new tools and programs to help older adults who experience disasters. Elizabeth Frankenberg, Ph.D., director of the Carolina Center for Population Aging and Health and distinguished professor of sociology at the University of North Carolina, Chapel Hill, leads a team that is investigating the aftermath of the 2004 Indian Ocean tsunami, a large-scale, unanticipated natural disaster. The NIA-funded Study of the Tsunami Aftermath and Recovery (STAR) study has followed more than 25,000 individuals since before the tsunami, collecting detailed data on exposures, recovery, health, and economic status. They have completed at least one post-tsunami interview with 98% of surviving original respondents, making it one of the largest datasets in the field.

In an analysis of STAR data from more than 12,000 adults over age 40, Frankenberg’s team examined the effectiveness of a post-tsunami housing reconstruction program. In the aftermath of the tsunami, billions of dollars were committed to the reconstruction of housing in damaged areas. Frankenberg and her colleagues found that for older adults, having permanent housing after a disaster lowered the chance of developing symptoms of PTSD. The team also discovered that those who moved into permanent housing after the tsunami had lower mortality rates in the decade following the disaster, when compared to people who moved into temporary housing. Frankenberg notes that these findings underscore the need for studies that examine not only the immediate but also the long-term effects of disasters.

In recent years, assistance agencies have become increasingly aware of the potential vulnerability of older adults during and after disasters. However, according to Frankenberg, “There’s not a consistent set of policies designed around the needs of older individuals, particularly with respect to the recovery phase.”

Before scientific findings can influence policy, researchers must establish a broad foundation of knowledge. “It would be premature for policies to flow directly from one study,” says Frankenberg. “It typically takes similar findings from multiple studies, and then perhaps a pilot program or demonstration project might be implemented, or an existing program strengthened or adapted.”

According to Frankenberg, research that identifies how different population subgroups are affected by a disaster, and the factors that underlie successful recovery, is critical for the design of effective policies and programs.

What’s next?

Researchers will continue to explore the effects of natural disasters and extreme weather on older adults and how different factors interact with each other. “An older adult with limited financial resources may also live in a rural area, be isolated from friends and family, take several medications, and have chronic illnesses that require regular medical care,” said NIA’s Nguyen. By understanding what makes older adults more vulnerable, researchers can identify ways to better support them. “Exploring how these factors influence each other will be essential to crafting effective interventions to improve the health and well-being of older adults who experience disaster,” Nguyen said.