Associations Between Anthropogenic Factors, Meteorological Factors, and Cause‐Specific Emergency Department Admissions.

Unpredictable emergency department (ED) admissions challenge healthcare systems, causing resource allocation inefficiencies. This study analyses associations between air pollutants, meteorological factors, and 2,655,861 cause‐specific ED admissions from 2014 to 2018 across 12 categories. Generalized additive models were used to assess non‐linear associations for each exposure, yielding Incidence Rate Ratios (IRR), while the population attributable fraction (PAF) calculated each exposure's contribution to cause‐specific ED admissions. IRRs revealed increased risks of ED admissions for respiratory infections (IRR: 1.06, 95% CI: 1.01–1.11) and infectious and parasitic diseases (IRR: 1.09, 95% CI: 1.03–1.15) during increased rainfall (13.21–16.97 mm). Wind speeds >12.73 km/hr corresponded to increased risks of ED admissions for respiratory infections (IRR: 1.12, 95% CI: 1.03–1.21) and oral diseases (IRR: 1.58, 95% CI: 1.31–1.91). Higher concentrations of air pollutants were associated with elevated risks of cardiovascular disease (IRR: 1.16, 95% CI: 1.05–1.27 for PM10) and respiratory infection‐related ED admissions (IRR: 2.78, 95% CI: 1.69–4.56 for CO). Wind speeds >12.5 km/hr were predicted to contribute toward 10% of respiratory infection ED admissions, while mean temperatures >28°C corresponded to increases in the PAF up to 5% for genitourinary disorders and digestive diseases. PM10 concentrations >60 μg/m3 were highly attributable toward cardiovascular disease (PAF: 10%), digestive disease (PAF: 15%) and musculoskeletal disease (PAF: 10%) ED admissions. CO concentrations >0.6 ppm were highly attributable to respiratory infections (PAF: 20%) and diabetes mellitus (PAF: 20%) ED admissions. This study underscores protective effects of meteorological variables and deleterious impacts of air pollutant exposures across the ED admission categories considered. Plain Language Summary: The unpredictability and variability of emergency department (ED) admissions load pose significant challenges for healthcare systems, as it can lead to a strain in resources. Understanding risk factors leading to higher ED admission loads provide an opportunity to anticipate surges, identify potential trends, and allocate resources in a pre‐emptive manner, thereby enhancing the responsiveness and preparedness of healthcare systems. Our analyses revealed that: (a) high total daily rainfall was negatively associated with ED admissions (b) mean temperature, while positively associated with ED admissions, typically had delayed effects on ED admissions (c) increased wind speed contributed disproportionately to increased ED admissions due to respiratory infections (d) increased ambient air pollutant concentrations, while positively associated with ED admissions due to most categories, had the greatest impact on the categories belonging to cardiorespiratory system disorders. Key Points: High total daily rainfall was negatively associated with emergency department (ED) admissions, while mean temperature was positively associated with ED admissionsIncreased wind speed contributed disproportionately to increased ED admissions due to respiratory infectionsIncreased ambient air pollutant concentrations had the greatest impact on the categories belonging to the cardiorespiratory system disorders [ABSTRACT FROM AUTHOR]