COVID-19 Outcome and Tobacco Product Use: Case-Control and Retrospective Cohort Studies Using Nationwide Samples
10.3346/jkms.2024.39.e103
- Author:
Seo Young KANG
1
;
Ye-Jee KIM
;
Hong-Jun CHO
Author Information
1. Department of Family Medicine, Uijeongbu Eulji Medical Center, Eulji University School of Medicine, Uijeongbu, Korea
- Publication Type:Original Article
- From:Journal of Korean Medical Science
2024;39(11):e103-
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background:Conflicting evidence exists regarding the association between smoking and the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the association between combustible cigarette (CC) smoking, noncombustible tobacco product (NCTP) use, and the use of any tobacco product with various coronavirus disease 2019 (COVID-19) outcomes.
Methods:A case-control study was conducted using the Korea Disease Control and Prevention Agency-COVID19-National Health Insurance Service (NHIS) cohort. A retrospective cohort study was conducted using 12,571,698 individuals from the NHIS cohort. Logistic regression evaluated the association between CC smoking, NCTP use, and use of any tobacco product with SARS-CoV-2 infection. Poisson regression evaluated the association between these forms of tobacco product use and COVID-19-related hospitalization and mortality.
Results:In the case-control study, we identified 30,878 cases of SARS-CoV-2 infection. The odds ratios (95% confidence intervals [CIs]) for SARS-CoV-2 infection were lower among current CC smokers (0.51, 0.48–0.54), current- and former-NCTP users (0.80, 0.74–0.88;0.82, 0.74–0.91), and current users of any tobacco product (0.52, 0.49–0.55) relative to never user controls. In retrospective cohort study, we identified 16,521 COVID-19-related hospitalization and 362 COVID-19-related deaths. The relative risks (95% CIs) for COVID-19-related hospitalization were lower among current CC smokers (0.51, 0.48–0.54) and current users of any tobacco product (0.53, 0.50–0.56) relative to never user controls. There was no association between the use of tobacco product and COVID-19-related mortality.
Conclusion:Current CC smokers and current users of any tobacco product showed reduced risk of SARS-CoV-2 infection and COVID-19-related hospitalization. It remains uncertain whether these relationships are causal.