Short‐term exposure to ambient air pollution and COVID‐19 severity during SARS‐CoV‐2 Delta and Omicron waves: A multicenter study

Abstract

AbstractAir pollution may affect the clinical course of respiratory diseases, including COVID‐19. This study aimed to evaluate the relationship between exposure of adult patients to mean 24 h levels of particulate matter sized <10 μm (PM10) and <2.5 μm (PM2.5) and benzo(a)pyrene (B(a)P) during a week before their hospitalization due to SARS‐CoV‐2 infection and symptomatology, hyperinflammation, coagulopathy, the clinical course of disease, and outcome. The analyses were conducted during two pandemic waves: (i) dominated by highly pathogenic Delta variant (n = 1440) and (ii) clinically less‐severe Omicron (n = 785), while the analyzed associations were adjusted for patient's age, BMI, gender, and comorbidities. The exposure to mean 24 h B(a)P exceeding the limits was associated with increased odds of fever and fatigue as early COVID‐19 symptoms, hyperinflammation due to serum C‐reactive protein >200 mg/L and interleukin‐6 >100 pg/mL, coagulopathy due to  d‐dimer >2 mg/L and fatal outcome. Elevated PM10 and PM2.5 levels were associated with higher odds of respiratory symptoms, procalcitonin >0.25 ng/mL and interleukin >100 pg/mL, lower oxygen saturation, need for oxygen support, and death. The significant relationships between exposure to air pollutants and the course and outcomes of COVID‐19 were observed during both pandemic waves. Short‐term exposure to elevated PM and B(a)P levels can be associated with a worse clinical course of COVID‐19 in patients requiring hospitalization and, ultimately, contribute to the health burden caused by SARS‐CoV‐2 variants of higher and lower clinical significance.