AUTHOR=Shaaban A. N. , Andersson F. , Peña S. , Caspersen I. H. , Magnusson C. , Orsini N. , Karvonen S. , Magnus P. , Hergens M. P. , Galanti M. R. 

TITLE=The Association Between Tobacco Use and Risk of COVID-19 Infection and Clinical Outcomes in Sweden: A Population-Based Study

JOURNAL=International Journal of Public Health

VOLUME=68

YEAR=2023

URL=https://www.ssph-journal.org/journals/international-journal-of-public-health/articles/10.3389/ijph.2023.1606175

DOI=10.3389/ijph.2023.1606175

ISSN=1661-8564

ABSTRACT=<p><bold>Background:</bold> The association between tobacco use and COVID-19 is controversial. During the early course of the pandemic, limited testing prevented studying a wide spectrum of clinical manifestations.</p><p><bold>Objective:</bold> To examine the potential causal association between tobacco use and COVID-19 during the second wave (1 October 2020–30 June 2021) of the pandemic in Stockholm, Sweden.</p><p><bold>Methods:</bold> A population-based cohort study was conducted in the Stockholm region of Sweden, with information on tobacco use collected prior to the pandemic. Adjusted relative risks (RR) of COVID-19 and 95% confidence intervals (CI) were calculated, contrasting current smokers and <italic>snus</italic> users to non-users of tobacco.</p><p><bold>Results:</bold> Compared with non-users of tobacco, current smokers had a lower risk of COVID-19 (RR 0.78, 95% CI = 0.75–0.81) and of hospitalisation for the disease. Current s<italic>nus</italic> users had a higher risk of COVID-19. Heavy smokers and <italic>snus</italic> users had longer hospital stays than non-users of tobacco.</p><p><bold>Conclusion:</bold> Tobacco use may have a different impact on the risk of being infected with SARS-CoV-2 and the risk of developing severe clinical manifestations. Further research is needed to determine the underlying mechanisms.</p>