Short-term exposure to ambient air pollution and individual emergency department visits for COVID-19: a case-crossover study in Canada

Eric Lavigne; Niilo Ryti; Antonio Gasparrini; Francesco Sera; Scott Weichenthal; Hong Chen; Teresa To; Greg J Evans; Liu Sun; Aman Dheri; Lionnel Lemogo; Serge Olivier Kotchi; Dave Stieb

doi:10.1136/thoraxjnl-2021-217602

Short-term exposure to ambient air pollution and individual emergency department visits for COVID-19: a case-crossover study in Canada

Thorax. 2023 May;78(5):459-466. doi: 10.1136/thoraxjnl-2021-217602. Epub 2022 Mar 31.

Authors

Eric Lavigne^{1

2}, Niilo Ryti³, Antonio Gasparrini^{4

5

6}, Francesco Sera⁷, Scott Weichenthal^{8

9}, Hong Chen^{10

11

12

13}, Teresa To^{10

13

14}, Greg J Evans¹⁵, Liu Sun⁸, Aman Dheri⁸, Lionnel Lemogo¹⁶, Serge Olivier Kotchi¹⁷, Dave Stieb^{2

11}

Affiliations

¹ Air Sectors Assessment and Exposure Science Division, Health Canada, Ottawa, Ontario, Canada eric.lavigne@hc-sc.gc.ca.
² School of Epidemiology & Public Health, University of Ottawa, Ottawa, Ontario, Canada.
³ Center for Environmental and Respiratory Health Research (CERH), University of Oulu, Oulu, Finland.
⁴ Department of Public Health Environments and Society, London School of Hygiene & Tropical Medicine, London, UK.
⁵ Centre for Statistical Methodology, London School of Hygiene & Tropical Medicine, London, UK.
⁶ Centre on Climate Change and Planetary Health, London School of Hygiene & Tropical Medicine, London, UK.
⁷ Department of Statistics, Computer Science and Applications "G. Parenti", University of Florence, Florence, Italy.
⁸ Air Sectors Assessment and Exposure Science Division, Health Canada, Ottawa, Ontario, Canada.
⁹ Department of Epidemiology, Biostatistics, and Occupational Health, McGill University Montreal, Montreal, Quebec, Canada.
¹⁰ Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
¹¹ Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada.
¹² Public Health Ontario, Toronto, Ontario, Canada.
¹³ Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
¹⁴ Child Health Evaluative Sciences, The Hospital For Sick Children, Toronto, Ontario, Canada.
¹⁵ Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada.
¹⁶ Environment and Climate Change Canada Montreal Office, Montreal, Ontario, Canada.
¹⁷ National Microbiology Laboratory, Public Health Agency of Canada, Saint-Hyacinthe, Ontario, Canada.

Abstract

Background: Ambient air pollution is thought to contribute to increased risk of COVID-19, but the evidence is controversial.

Objective: To evaluate the associations between short-term variations in outdoor concentrations of ambient air pollution and COVID-19 emergency department (ED) visits.

Methods: We conducted a case-crossover study of 78 255 COVID-19 ED visits in Alberta and Ontario, Canada between 1 March 2020 and 31 March 2021. Daily air pollution data (ie, fine particulate matter with diameter less than 2.5 µm (PM_2.5), nitrogen dioxide (NO₂) and ozone were assigned to individual case of COVID-19 in 10 km × 10 km grid resolution. Conditional logistic regression was used to estimate associations between air pollution and ED visits for COVID-19.

Results: Cumulative ambient exposure over 0-3 days to PM2.5 (OR 1.010; 95% CI 1.004 to 1.015, per 6.2 µg/m³) and NO₂ (OR 1.021; 95% CI 1.015 to 1.028, per 7.7 ppb) concentrations were associated with ED visits for COVID-19. We found that the association between PM_2.5 and COVID-19 ED visits was stronger among those hospitalised following an ED visit, as a measure of disease severity, (OR 1.023; 95% CI 1.015 to 1.031) compared with those not hospitalised (OR 0.992; 95% CI 0.980 to 1.004) (p value for effect modification=0.04).

Conclusions: We found associations between short-term exposure to ambient air pollutants and COVID-19 ED visits. Exposure to air pollution may also lead to more severe COVID-19 disease.

Keywords: COVID-19.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants* / adverse effects
Air Pollutants* / analysis
Air Pollution* / adverse effects
Air Pollution* / analysis
COVID-19* / epidemiology
Cross-Over Studies
Emergency Service, Hospital
Environmental Exposure / adverse effects
Environmental Exposure / analysis
Humans
Nitrogen Dioxide / analysis
Nitrogen Dioxide / toxicity
Ontario / epidemiology
Particulate Matter / adverse effects
Particulate Matter / analysis

Substances

Nitrogen Dioxide
Air Pollutants
Particulate Matter

Abstract

Publication types

MeSH terms

Substances

Grants and funding