Superstorm Sandy's deadly effects lingered for years, study finds

Nearly 150 people died in the immediate aftermath of Superstorm Sandy, which made landfall on Long Island Oct. 29, 2012. But many more died in the following years from lingering effects, according to new research released Wednesday that focused on the particular vulnerability of older adults in the wake of devastating storms.

The study, from Arnab Ghosh, assistant professor of medicine at Weill Cornell, and his colleagues, found that people who remained in neighborhoods flooded during the storm were at higher risk of dying even five years afterward, compared with those in nearby areas that were not flooded.

Long Island tallied fewer deaths than other regions in Sandy's path, but the results show that destructive storms have reverberating effects on health long after floodwaters recede. Experts stress that these results also highlight the need for better disaster planning and recovery, since hurricane seasons will grow more fierce as the planet heats up. 

"Climate-amplified hurricanes and hurricane-related floods are expected to increase into the future," the authors wrote, so it’s important to understand "the long-term health effects of those most vulnerable."

The study, which was published Wednesday in the journal Frontiers in Public Health, tracked mortality rates from all causes for nearly 300,000 people in the tristate area age 65 and older who were recipients of Medicare. They included only those who continued to live in ZIP codes that experienced severe flooding during the storm.

On average, the rate of death in those areas was 9% higher than those living in nearby neighborhoods that weren’t badly flooded. The risk varied by region. In New York City, there was an 8% increase in mortality; in Connecticut it was 19%. In the rest of coastal New York — that is, Long Island — and in New Jersey, the increase was insignificant.

Those regional patterns were unexpected, the researchers said, because typically worse health outcomes after hurricanes correlate with lower-income areas, and the flooded Connecticut ZIP codes were on average more affluent than the flooded zones in New York and New Jersey.

Ghosh speculated that the averaged results may have obscured the presence of low-income neighborhoods in places like Bridgeport, Connecticut, surrounded by higher-income ones. And the authors speculated that differences that led to less impact on Long Island than elsewhere might be attributed to differences in "region-specific policies, infrastructure disruption, and disaster relief."

Ghosh and his colleagues are working on a follow-up study on cardiovascular disease after Sandy, because "after a hurricane, there's a lot of evidence to say that you're more likely to get a heart attack," Ghosh said.

Less savings, support among possible reasons

Experts have identified a range of reasons for these belated "excess deaths."

People in flooded areas "may use retirement savings to repair damage," the authors of a separate study published last year suggested, which may leave less money for future health care needs. If family members move away, those left behind have less support if they later fall ill, the researchers, Rachel Young, a postdoc at the University of California-Berkeley, and Solomon Hsiang, a professor of environmental policy at Stanford University, said. And public funds may be diverted from health care investments to disaster recovery. 

The cause of deaths in the immediate aftermath include drowning, injuries, "acute stress" that can lead to heart attacks and strokes, and in some cases "being neglected in a care home," Robbie Parks, an environmental epidemiologist at Columbia University’s Mailman School of Public Health, explained in an interview with Newsday.

In the longer term, Parks said, "structural issues" become a critical factor, such as access to health care and to transportation.

After a storm like Sandy, "you're looking at the need to rebuild or recover everything from housing to your mental health and health care systems," said Samantha Montano, assistant professor of emergency management at the Massachusetts Maritime Academy, as well as "addressing the return of social services."

Older people are especially vulnerable when these systems are frayed, in part because they are more likely to have existing health problems. Impaired mobility "is one of the huge factors," Parks said, "combined with isolation." Older people may also be "not quite as nimble as younger groups" with technology, which will complicate efforts to connect with telehealth for example, or to apply for disaster aid.

Storms like Sandy also erode social networks that older folks depend on for company and for support. "Your family, your friends, your routines — these things are important, particularly as you get older," Ghosh said.

Those who remain in place are affected, because others may be displaced.

"When these devastating events hit, we'd be worried about these informal networks," he added. "All these care structures are disrupted."

Remarkably, the risk of dying in the aftermath of major storms hasn’t changed in nearly 100 years. Young and Hsiang in their 2024 study discovered the "average" tropical storm since the 1930s generated between 7,000 and 11,000 excess deaths. They found "no evidence that earlier storms had an impact different from later storms."

Ultimately, Montano said, "We need to make a more effective and efficient and equitable recovery process for people and communities."