Heat-Related Deaths Surge in the United States Over 24 Years

TOPLINE: 

Heat-related deaths and age-adjusted mortality rates have increased from 1999 to 2023 in the United States, with the highest number of deaths (2325 cases) recorded in 2023.

METHODOLOGY:

• Researchers analyzed all deaths from 1999 to 2023 with external heat as the underlying or a contributing cause.
• Deidentified public data were obtained from the Centers for Disease Control and Prevention’s WONDER platform, which combines death counts with population estimates.
• Age-adjusted mortality rates (AAMRs) per 100,000 person-years were extracted for each year.

TAKEAWAY:

• A total of 21,518 heat-related deaths were recorded, with an AAMR of 0.26 per 100,000 person-years.
• From 1999 to 2023, the number of heat-related deaths in the United States increased by 117%, with the AAMR rising by 63%.
• The highest number of heat-related deaths (2325 cases) was recorded in 2023, whereas the lowest number (311 cases) was recorded in 2004.
• A nonsignificant decrease of 1.4% per year in the AAMR was observed from 1999 to 2016; this was followed by a significant increase of 16.8% per year from 2016 to 2023 (P =.002).

IN PRACTICE:

“As temperatures continue to rise because of climate change, the recent increasing trend is likely to continue. Local authorities in high-risk areas should consider investing in the expansion of access to hydration centers and public cooling centers or other buildings with air conditioning,” the authors wrote.

SOURCE:

The study was led by Jeffrey T. Howard, PhD, University of Texas at San Antonio. It was published online on August 26, 2024, in JAMA.

LIMITATIONS:

The potential for misclassification of causes of death may have led to an underestimation of heat-related mortality rates. Increasing awareness over time may have introduced bias in the data. The lack of data for vulnerable subgroups limited the generalizability of the findings.

DISCLOSURES:

No funding information was provided for the study. The authors declared no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.