• Older adults with dementia are particularly vulnerable during disasters
  • The mortality risks were lower in counties that did not experience a hurricane
  • Dementia and climate change are among the issues the world is grappling with today

Older adults with dementia may have heightened death risks after being exposed to a hurricane, a study has found. This highlights the need to also adapt for them in response to such disasters amid the impacts of climate change.

For their study, which was published in JAMA Network Open, a team of researchers looked at the mortality changes among older adults with Alzheimer's disease and other related dementias (ADRD) after being exposed to hurricanes.

Although previous studies have found mortality increases "in general" after hurricanes, the data is unclear when it comes to older adults with ADRD, they noted.

"Older adults living with Alzheimer disease [sic] and other related dementias (ADRD) are especially vulnerable during disaster events because of their dependence on others during crises," the researchers wrote. "Therefore, we examined mortality changes among older adults with ADRD exposed to major U.S. hurricanes."

To find out, they looked at data from administrative claims among adults aged 65 and above who were affected by Hurricanes Harvey (2017), Irma (2017) and Florence (2018). The population consisted of 346,171 beneficiaries from the counties affected by the hurricanes. They looked at the monthly and annual all-cause mortality among those in the population with versus without ADRD.

There were 54,340 deaths among those with ADRD in the year following the hurricane exposure. Indeed, the researchers found increased mortality among the beneficiaries with ADRD after Hurricanes Harvey and Irma.

"Hurricane exposure was associated with increased mortality among the ADRD population after two of the three hurricanes," the researchers noted. "Mortality risks were lower among beneficiaries in counties that did not experience a disaster."

The risk was highest among those 85 years old and older, according to the University of Michigan's news release. In this age range, those with dementia had a 9% increased risk of death compared to those in the age range without it.

"The higher mortality risks associated with Hurricane Harvey are consistent with the larger scope, scale and impact of this storm," the researchers explained. "As anticipated, mortality risk was highest among more vulnerable ADRD subgroups, including the oldest individuals and those dually eligible."

Mortality peaked some three to six months after the exposure to Hurricanes Harvey and Irma. This suggests that the increases weren't a direct or immediate result of the hurricanes, according to the researchers. Instead, it may have been a result of disruptions in their routines and access to health care.

Further, the mortality risk among those with dementia persisted regardless of whether they moved from the area after the storm or not.

The results of the study highlight a particular vulnerability of the population that, perhaps, people don't immediately think of during such disasters. And on a broader scale, this also shines a light on two of the major issues that the world is facing and grappling with today — issues that one may not immediately think to link with each other: dementia and climate change.

Worldwide, it is estimated that about 55 million people are living with dementia. This number could grow to 78 million by 2030 and 139 million by 2050, according to the World Health Organization (WHO).

In the U.S., the number of people with dementia aged 65 and above was already 5 million as of 2014. Should the trends continue, this could rise to 14 million by 2060.

Contrary to what some may think, dementia is not an inevitable part of aging. It is not exactly a specific disease but a syndrome that can lead to deterioration in cognitive function beyond what one might expect from normal aging. And not only does it have health impacts on the patients themselves and the people around them, but it also has great psychological, social and even economic effects.

It was estimated that in 2019, the global cost of dementia in the U.S. was $1.3 trillion — a mounting cost that may increase to $1.7 trillion by 2030 and even $2.8 trillion by 2050.

Dementia is said to be one of the leading causes of death in the world and among the major causes of disability and dependence among older people.

With the results of the current study, the conversation has opened for yet another vulnerability for these members of the community: hurricanes. As the researchers noted, people with dementia are particularly vulnerable to disasters. But with the global problem of climate change, we are also beginning to see changes in these kinds of disasters that may potentially make things a little more complicated.

Indeed, hurricanes have been predicted to cause more intense rainfall, an increase in wind intensity and even a rise in coastal flood risk because of the rising sea levels.

"Scientists have long predicted that climate change would increase extreme rainfall events," NASA said. "In a warmer world, there is simply more moisture in the air in the form of gaseous water vapor."

The people often perceived as the most vulnerable ones to climate change include those who are living in floodplains, coastlines and those who reside in places that are often affected by storms. Further, those living in poverty may also not be as able to prepare for such extreme events, the Environmental Protection Agency (EPA) noted.

But climate change may also have health impacts, and children, those with disabilities and the older population are among those who are said to be most at risk for climate-related health impacts.

While it's only natural that people are advised to be prepared for these weather events, especially when the hurricane season arrives, the current study highlights those with ADRD as a community of people who are especially vulnerable to such destructive and disruptive events. And it begs the question of what can be done to make sure their needs are also met when these disasters come and go.

"As climate change worsens, disasters will increase along with the numbers of people with dementia," the University of Michigan noted in its news release.

Unfortunately, despite the grim statistics on dementia, it appears that the world may be "failing" to address this issue.

Only about a quarter of the world's countries had the plan to support people with dementia and their families, the WHO reported in 2021. And that's even with the data showing a growing number of people living with the condition.

"The world is failing people with dementia, and that hurts all of us," the WHO noted. "(T)argets alone are not enough. We need concerted action to ensure that all people with dementia are able to live with the support and dignity they deserve."

The results of the study may perhaps serve as a wake-up call that it's about time for us to also keep people with ADRD in mind when preparing for the inevitable arrival of these disasters — as the world fights but also braces itself for the impacts of climate change.

This includes proper policy as well as ample response.

"The important message is that older adults with dementia have unique needs, most notably that during a disaster, they are almost entirely dependent on caregivers due to their lack of awareness of the crisis," study first author Anne Bell of the U-M School of Nursing said in the university release. "I think if anything, there is new attention to the needs of older adults during a disaster, and this study is one of an emerging body of evidence that is working to better support the needs of older adults before, during and after disasters."

Flooding in Texas during Hurricane Harvey, Aug. 31, 2017. According to the Climate Science Special Report released on Nov. 2, heavy precipitation events are becoming more frequent and intense in most regions of the world. Getty