Air Pollution Exposure and COVID-19 Outcomes: A Systematic Review and Meta-analysis of Short- and Long-term Effects

Abstract

Our objective was to determine the relationship between short-term and long-term exposure to air pollution and COVID-19 mortality and morbidity through a systematic review and meta-analysis. To do so, Scopus, PubMed, and Web of Science databases were searched for original studies up to February 1, 2023. Observational studies reporting risk estimates for the association between air pollution exposure and COVID-19 outcomes were included. The methodological quality of the selected articles was assessed using the Newcastle-Ottawa scale (NOS). Pooled estimates were calculated using a random effects model. We employed the I² statistic and chi-square test to assess heterogeneity among studies. Egger’s and Begg’s tests were used to evaluate potential publication bias. A total of 2823 articles were identified in the initial database search. After screening, 12 studies met the inclusion criteria and were included in the meta-analysis. The results indicated a significant association between PM₁₀ and O₃ exposure and COVID-19 mortality, with relative risks of 1.02 (95% confidence interval: 1.01 to 1.04) and 1.09 (95% confidence interval: 1.04 to 1.14), respectively. Our meta-analysis suggests that exposure to O₃ and PM₁₀ is associated with an increased risk of COVID-19 mortality. Additionally, the study found a significant link between exposure to NO₂ , PM_2.5, and PM₁₀ and increased COVID-19 mortality, with PM_2.5 showing the strongest association. These findings underscore the need for effective policies to mitigate the health impacts of air pollution and highlight the importance of integrated strategies to address the broader effects of climate change.

Keywords: Air pollution, COVID-19, Nitrogen dioxide, Mortality, Morbidity, Systematic reviews,