Changes in emergency department visit volume before, during and after the COVID-19 pandemic, with an exploratory assessment of air pollution: a preliminary ecological study from Poznań, Poland
DOI:
https://doi.org/10.12923/2083-4829/2026-0010Słowa kluczowe:
emergency department, COVID-19, air pollution, environmental epidemiology, ecological study, PoznańAbstrakt
Introduction. Hospital Emergency Departments provide 24-hour care and their workload reflects clinical, organisational, epidemiological and environmental factors. The COVID-19 pandemic changed emergency care use, while air pollution may contribute to acute health events.
Aim. The study aimed to assess changes in Emergency Department hospitalisations in Poznań before, during and after COVID-19, considering selected air pollutants.
Material and methods. Monthly data from 2018-2025 on Emergency Department hospitalisations in Poznań and mean concentrations of PM10, PM2.5, CO and NO2 were analysed. Hospitalisation data came from the National Health Fund and environmental data from the Chief Inspectorate for Environmental Protection. The following four periods were compared: 2018-2019, 2020-2021, 2022-2023 and 2024-2025. Kruskal-Wallis, post-hoc and Spearman tests were used.
Results. The number of hospitalisations differed significantly between periods (p < 0.001). Median monthly values decreased from 8,233.5 in 2018-2019 to 6,626.5 in 2020-2021, then increased to 10,732 in 2022-2023 and 21,312.5 in 2024-2025. Differences were significant for PM10, CO and NO2, but not PM2.5. PM10, CO and NO2 generally decreased. In 2018-2019, all pollutants correlated negatively with hospitalisations, while in 2022-2025, this persisted only for NO2. The environmental component was exploratory, not causal.
Conclusions. The rise observed between 2024-2025 cannot be explained solely by changes in the analysed pollutants. Nega tive correlations probably reflect confounding factors, including post-pandemic organisational and epidemiological changes. Further analyses using daily pollution data and focusing on selected cardiovascular and respiratory diseases are needed.
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Prawa autorskie (c) 2026 Michał Surdacki, Kacper Nijakowski, Teresa Matthews-Brzozowska (Autor)
Utwór dostępny jest na licencji Creative Commons Uznanie autorstwa – Użycie niekomercyjne – Bez utworów zależnych 4.0 Międzynarodowe.
