The study found that the cold kills more Americans every year

Even as the climate warms, the cold becomes a more deadly threat to Americans. New research this month shows that cold-related deaths have increased significantly in the United States over the past two decades.

Researchers at Harvard Medical School conducted the study, which aims to better count deaths caused by cold temperatures in the United States. They found that the country’s cold-related death rate has doubled since the late 1990s, with deaths particularly increasing in recent years. Researchers say important risk factors for higher deaths likely include extreme weather events linked to climate change, homelessness and social isolation.

Extreme temperatures at both ends of the thermometer can be life-threatening. While recent research has shown that heat-related deaths have risen in recent decades, cold weather tends to be deadlier overall. Study 2021 Found That cold was responsible for about three-quarters of deaths from extreme temperatures worldwide in 2019, for example (there were an estimated 1.7 million deaths overall that year).

The Harvard researchers point out that cold-related deaths in the United States have been little studied, and little is known about how this burden has changed over time. To address this knowledge gap, they analyzed death certificate data collected by the Centers for Disease Control and Prevention, focusing specifically on deaths in which the cold was recorded as an underlying or contributing cause.

The researchers found that between 1999 and 2022, there were just over 40,000 cold-related deaths in the United States. After adjusting for age, they found that the death rate rose from 0.44 cold-related deaths per 100,000 people in 1999 to 0.92 cold-related deaths per 100,000 people in 2022. Much of this jump was the result of a large annual increase in deaths between 2017 and 2017. And 2017. and 2022. The results reached by the team were: published This month in the magazine Gamma.

“There has been a valid focus on heat-related deaths given the undeniable nature of global warming,” study lead author Rishi Vadera, a cardiologist and public health researcher at Harvard University, told Gizmodo in an email. “However, the results of our study serve as a stark reminder that cold-related deaths also remain an important public health issue.”

While their study was not designed to identify any specific reasons for this increase, Vadera and his colleagues highlight some possible factors.

It is known that climate change increases the risks of both hot weather and… Cold extreme weather eventsFor example. But it’s also possible that more Americans today are at greater risk of being excluded from the cold than before, especially people in precarious living situations, Vadera notes.

“For example, we know that the number of unprotected people in the United States has risen over the past several years — and these populations are the most exposed to outdoor weather, including cold snaps,” he said.

Levels of homelessness in the United States have generally risen since 2016 (the early years of the COVID-19 pandemic were… A notable exception(Thanks in part to generous relief programs). In 2023, chronic homelessness Transgression Record numbers were set in 2007, when modern data collection efforts began, according to the Department of Housing and Urban Development (its report this year has not yet been released). Substance use and social isolation may also increase people’s risk of exposure to unsafe conditions, including temperature.

Certain trends emerged in the team’s data that show who is most at risk for cold-related deaths. Regionally, the death rate was highest in the Midwest, where winters can be particularly harsh, for example. The highest death rates across racial and ethnic groups were seen among Native Americans and blacks, respectively, and the highest age-specific death rates were seen in people over 75 years of age.

The authors say more research needs to be done to clarify why cold-related deaths are increasing. At the same time, there are already steps policymakers can and should take to prevent this tragic loss of life, such as ensuring that vulnerable populations live in homes with reliable indoor heating or expanding access to warming centers.

“Our findings should raise awareness that injury and death due to exposure to cold weather is possible — especially for older populations with more health conditions, unprotected people more exposed to outdoor weather, and low-income populations who may not have access to To enough food. “Internal heating,” Vadera said.