Weather data could warn of cardiac arrest risk several days in advance
· Medical Xpressedited by Gaby Clark, reviewed by Robert Egan
Gaby Clark
Scientific Editor
Meet our editorial team
Behind our editorial process
Robert Egan
Senior Editor
Meet our editorial team
Behind our editorial process Editors' notes
This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility:
fact-checked
peer-reviewed publication
trusted source
proofread
The GIST Add as preferred source
Weather data could help predict up to three days in advance when the number of out-of-hospital cardiac arrests is likely to rise above average, according to a nationwide study of more than 114,000 cases by researchers from Semmelweis University, the Budapest University of Technology and Economics, and the Hungarian National Ambulance Service.
The study, published in Public Health, found that lower temperatures emerged as one of the most important weather-related risk factors examined. In the future, models based on weather forecasts could help people with cardiovascular disease and their families prepare for higher-risk periods while supporting ambulance services and hospitals in managing expected increases in demand.
The researchers compared data on out-of-hospital cardiac arrests that occurred between November 2018 and December 2023 with daily meteorological indicators, including temperature, wind speed, atmospheric pressure, humidity and air quality.
Why predicting cardiac arrest cases matters
Out-of-hospital cardiac arrest (OHCA) is one of the leading causes of death in developed countries. In Europe, there are an estimated 67–170 cases per 100,000 people each year, while survival remains below 10%. Identifying factors that can predict an expected rise in case numbers could help emergency medical services prepare, raise public awareness of the importance of rapid intervention and resuscitation and, in the longer term, contribute to improving survival rates.
The analysis found that falling temperatures were among the most important weather-related risk factors for cardiac arrest: Every 1°C decrease in average temperature was associated with a 1.4% increase in the daily number of out-of-hospital cardiac arrests. A seasonal comparison also showed that nearly 18% more such events occurred in winter than in summer.
The findings suggest that it is not only sudden drops in temperature that may pose a risk, but lower temperatures in general. Rapid changes may nevertheless be particularly important: A daily temperature drop of more than 5°C could serve as a warning signal in an early warning system.
One of the study's key findings was that the effects of weather changes may not be immediate: The number of out-of-hospital cardiac arrests may rise up to three days later. This could make it possible to develop early warning systems capable of predicting increased demand on health care services several days in advance.
"In a previous study, we examined how extreme cold and heat affect the incidence of out-of-hospital cardiac arrest. This time, we went one step further and investigated whether weather patterns could be used to predict when higher-than-average numbers of cases are likely to occur. If this proves feasible, ambulance services and hospitals could prepare for increased demand several days in advance," said Dr. Endre Zima, professor at the Heart and Vascular Center of Semmelweis University and lead researcher of the study.
The researchers developed a predictive model that used meteorological data to estimate the expected daily number of out-of-hospital cardiac arrests.
"By combining meteorological and ambulance service data, the model could predict one to three days in advance when the number of out-of-hospital cardiac arrests is likely to rise above average. It does not estimate an individual's risk, but rather the number of cases expected nationwide," said Dr. Ádám Pál-Jakab, resident physician and Ph.D. student at the Heart and Vascular Center of Semmelweis University and first author of the study.
The researchers had to determine not only which atmospheric parameters had the greatest influence on the number of cardiac arrests, but also how to use them to build a reliable predictive model.
"One of the biggest challenges in developing the model was determining which days could genuinely be considered outliers and then examining whether these were associated with weather-related factors. Based on this, we were able to build a model that uses previous data to estimate expected case numbers," added Dr. Brigitta Szilágyi, associate professor at the Budapest University of Technology and Economics and Corvinus University of Budapest, and co-author of the study.
The next step could be to develop an early warning system that uses weather forecasts to help ambulance services and hospitals plan capacity and manage expected increases in demand. In the future, such a system could also alert people with cardiovascular disease and their families to higher-risk periods, helping them pay closer attention to warning symptoms and seek medical attention sooner when necessary.
Publication details
Ádám Pál-Jakab et al, Meteorological associations with out-of-hospital cardiac arrest: A national population-based time-series analysis, Public Health (2026). DOI: 10.1016/j.puhe.2026.106145
Journal information: Public Health
Key medical concepts
Out-of-Hospital Cardiac ArrestCardiovascular Diseases
Clinical categories
CardiologyEmergency medicineCommon illnesses & Prevention Provided by Semmelweis University Who's behind this story?
Gaby Clark
MA in English, copy editor since 2021 with experience in higher education and health content. Dedicated to trustworthy science news. Full profile →
Robert Egan
Bachelor's in mathematical biology, Master's in creative writing. Well-traveled with unique perspectives on science and language. Full profile →
Citation: Weather data could warn of cardiac arrest risk several days in advance (2026, September 15) retrieved 15 September 2026 from https://medicalxpress.com/news/2026-09-weather-cardiac-days-advance.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.