Cold Weather Linked to Higher Rates of Out-of-Hospital Cardiac Arrests

A collaborative study by researchers at Semmelweis University, Budapest University of Technology and Economics, and the Hungarian National Ambulance Service examined over 114,000 out-of-hospital cardiac arrests recorded between November 2018 and December 2023. The analysis revealed that each one-degree Celsius decrease in average temperature was associated with a 1.4% rise in daily cardiac arrests, and overall winter periods produced about 18% more cases than summer.

Rapid temperature drops exceeding five degrees Celsius emerged as a particularly strong warning signal. Importantly, the increased risk can manifest up to three days after the cold snap, indicating a lag effect. The authors propose that integrating weather data into predictive models could allow ambulance services and hospitals to allocate resources more efficiently and give patients with heart conditions time to take precautionary measures.