Effect of short-term exposure to air pollution on COVID-19 mortality and morbidity in Iranian cities

Mostafa Hadei; Philip K Hopke; Abbas Shahsavani; Alireza Raeisi; Ahmad Jonidi Jafari; Maryam Yarahmadi; Mohsen Farhadi; Masoumeh Rahmatinia; Shahriar Bazazpour; Anooshiravan Mohseni Bandpey; Alireza Zali; Majid Kermani; Mohmmad Hossien Vaziri; Mehrab Aghazadeh

doi:10.1007/s40201-021-00736-4

Effect of short-term exposure to air pollution on COVID-19 mortality and morbidity in Iranian cities

J Environ Health Sci Eng. 2021 Oct 28;19(2):1807-1816. doi: 10.1007/s40201-021-00736-4. eCollection 2021 Dec.

Authors

Mostafa Hadei¹, Philip K Hopke^{2

3}, Abbas Shahsavani^{4

5}, Alireza Raeisi⁶, Ahmad Jonidi Jafari⁷, Maryam Yarahmadi⁸, Mohsen Farhadi⁸, Masoumeh Rahmatinia⁵, Shahriar Bazazpour⁵, Anooshiravan Mohseni Bandpey⁴, Alireza Zali⁹, Majid Kermani⁷, Mohmmad Hossien Vaziri¹⁰, Mehrab Aghazadeh⁸

Affiliations

¹ Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
² Center for Air Resources Engineering and Science, Clarkson University, Potsdam, NY 13699 USA.
³ Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642 USA.
⁴ Air Quality and Climate Change Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁵ Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁶ Department of Internal Medicine, School of Medicine, Tehran University of Medical Sciences, Shiraz, Iran.
⁷ Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran.
⁸ Environmental and Occupational Health Center, Ministry of Health and Medical Education, Tehran, Iran.
⁹ Department of Neurosurgery, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
¹⁰ Workplace Health Promotion Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Abstract

Purpose: The association between air pollutant (PM_2.5, PM₁₀, NO₂, and O₃) concentrations and daily number of COVID-19 confirmed cases and related deaths were evaluated in three major Iranian cities (Tehran, Mashhad, and Tabriz).

Methods: Hourly concentrations of air pollutants and daily number of PCR-confirmed cases and deaths of COVID-19 were acquired (February 20^th, 2020 to January 4^th, 2021). A generalized additive model (GAM) assuming a quasi-Poisson distribution was used to model the associations in each city up to lag-day 7 (for mortality) and 14 (for morbidity). Then, the city-specific estimates were meta-analyzed using a fixed effect model to obtain the overall relative risks (RRs).

Results: A total of 114,964 confirmed cases and 21,549 deaths were recorded in these cities. For confirmed cases, exposure to PM_2.5, NO₂, and O₃ for several lag-days showed significant associations. In case of mortality, meta-analysis estimated that the RRs for PM_2.5, PM₁₀, NO₂, and O₃ concentrations were 1.06 (95% CI: 0.99, 1.13), 1.06 (95% CI: 0.93, 1.19), 1.15 (95% CI: 0.93, 1.38), and 1.07 (95% CI: 0.84, 1.31), respectively. Despite several positive associations with all air pollutants over multiple lag-days, COVID-19 mortality was only significantly associated with NO₂ on lag-days 0-1 and 1 with the RRs of 1.35 (95% CI: 1.04, 1.67) and 1.16 (95% CI: 1.02, 1.31), respectively.

Conclusion: This study showed that air pollution can be a factor exacerbating COVID-19 infection and clinical outcomes. Actions should be taken to reduce the exposure of the public and particularly patients to ambient air pollutants.

Supplementary information: The online version contains supplementary material available at 10.1007/s40201-021-00736-4.

Keywords: Coronavirus; Nitrogen dioxide; Pandemic; Particulate matter; SARS-CoV-2.