Two heat waves in the summer of 2025 were associated with more than 13,000 additional emergency department visits across 19 Eastern states, according to research published Monday in Nature Health. The more consequential finding may be how quickly researchers were able to see it.
The team analyzed 8.1 million emergency department visits from the summers of 2023 through 2025 using de-identified electronic health records, and reported that the records were available within one week of each visit. Heat and health studies have traditionally relied on insurance claims that arrive 6 to 18 months later, long after the season in which officials might have acted.
