Hot weather appears to be triggering more frequent hospital visits for children with asthma.
Symptoms of the lung condition, such as breathlessness and wheezing, are more commonly associated with cold weather. To better understand the impact of hot temperatures, Morgan Ye at the University of California, San Francisco (UCSF), and her colleagues studied electronic health data from UCSF Benioff Children’s Hospitals.
The data included records on asthma hospitalisations and the patients’ addresses. The researchers used information from PRISM Climate Group at Oregon State University to obtain temperature records at the patients’ homes every day from June to September between 2017 and 2020.
The researchers defined heatwaves in 18 different ways. By looking at the range of temperatures that occurred over these periods, they considered it a heatwave if it fell in the top 99 per cent of these temperatures, or the top 97.5 per cent, or the top 95 per cent, and so on.
Presenting their results at the American Thoracic Society conference in San Diego, California, this week, the researchers found that across all of the heatwave definitions, these temperatures were associated with 19 per cent higher odds, on average, of a child with asthma being admitted to hospital, compared with when there wasn’t a heatwave.
While further research is required, hot weather can contribute to smog and ozone pollution, which may inflame or irritate the airways, says Ye.
“As we continue to see global temperatures rise due to human-generated climate change, we can expect a rise in health-related issues as we observe longer, more frequent and severe heatwaves,” she says.
Children are particularly vulnerable to extreme heat, says Stephanie Holm at the UCSF’s Western States Pediatric Environmental Health Specialty Unit. Speaking of the researchers’ approach to defining heatwaves, she says: “The fact that their results were robust to different definitions of extreme heat is powerful.”