Researchers at Mass General Brigham have uncovered a troubling trend: over the past 25 years, more than 69,000 deaths in the United States have been attributed to extreme temperatures, both hot and cold. This significant finding, published in the Annals of Internal Medicine, sheds light on the disproportionate impact of temperature-related mortality on certain populations.
The study, led by Dr. Shady Abohashem, MD, MPH, of the Cardiovascular Imaging Research Center at Massachusetts General Hospital, provides a comprehensive assessment of deaths linked to non-optimal temperatures. “Our findings show that both heat and cold exposure continue to claim thousands of lives every year in the United States, deaths that are largely preventable,” Abohashem stated. The research utilized data from the Centers for Disease Control and Prevention’s WONDER platform, analyzing death certificates that listed temperature as a contributing or underlying cause.
Understanding the Data
Between 1999 and 2024, the U.S. recorded 69,713,971 deaths, with 69,256 of these linked to extreme temperatures. The study found that 35% of these were heat-related, while a staggering 65% were due to cold exposure. “While most temperature-related deaths are still driven by cold exposure, heat-related deaths are expected to rise as climate change accelerates,” Abohashem noted.
The analysis revealed that older adults and males experienced higher mortality rates due to temperature extremes. Moreover, racial disparities were evident, with Black individuals facing the highest heat-related mortality rates, more than double those of white individuals. Cold-related mortality was also highest among Black populations, followed by Whites and Hispanics.
Implications of Climate Change
This development follows growing concerns about climate change and its impact on public health. “Climate change increases risks of severe weather events, and our findings underscore the need for targeted adaptation strategies,” Abohashem emphasized. These strategies include improving housing quality, access to cooling and heating, and implementing early-warning systems to protect vulnerable groups.
As climate extremes intensify, the study highlights the importance of understanding which populations are most at risk. This knowledge is crucial for shifting public health strategies to better protect those disproportionately affected by temperature-related hazards.
Historical Context and Future Directions
Historically, temperature-related deaths have been a concern, but the current study provides a more nuanced understanding by examining both ends of the temperature spectrum. Prior research often focused on either heat or cold, but rarely both in a comprehensive manner. The current findings emphasize the need for a dual approach in addressing temperature-related mortality.
Looking ahead, the authors suggest that public health initiatives must adapt to the realities of a changing climate. “The results help us understand which populations may be disproportionately affected so public health strategies can shift accordingly,” Abohashem concluded.
Research and Funding
The study was conducted by a team including Ibrahim Hassan, Ibrahim Alghzlawi, Lauren Ferguson, and Joseph Allen. Notably, Dr. Abohashem’s work is supported by the American Heart Association’s Second Century Early Faculty Independence Award. The funders did not influence the study’s design, data collection, or publication decisions.
The paper, titled “Temperature-related deaths in the US, 1999 – 2024,” can be accessed in the Annals of Internal Medicine under DOI:10.7326/ANNALS-25-01006.
As the U.S. grapples with the dual threats of heat and cold, the study’s insights offer a crucial roadmap for mitigating the impact of climate change on human health. The next steps will involve translating these findings into actionable policies and interventions to safeguard the most vulnerable communities.
