ASSOCIATION BETWEEN TOBACCO SMOKING AND COVID-19 OUTCOMES: A RETROSPECTIVE COHORT STUDY
Author(s)
Melissa Edgar, MD1, Austin DeBoer, MD2, Pegah Farrokhi, PharmD3, Zachary Lundstrom, MD4, Swapna Ravi, MD5;
1University of Minnesota, Medical School, Duluth, MN, USA, 2University of Minnesota, Duluth, MN, USA, 3University of Minnesota, College of Pharmacy, Minneapolis, MN, USA, 4Department of Internal Medicine, St. Luke’s, Duluth, MN, USA, 5Department of Internal Medicine, Gundersen Health System, La Crosse, WI, USA
1University of Minnesota, Medical School, Duluth, MN, USA, 2University of Minnesota, Duluth, MN, USA, 3University of Minnesota, College of Pharmacy, Minneapolis, MN, USA, 4Department of Internal Medicine, St. Luke’s, Duluth, MN, USA, 5Department of Internal Medicine, Gundersen Health System, La Crosse, WI, USA
OBJECTIVES: Published literature demonstrates conflicting findings regarding the relationship between tobacco smoking and COVID-19 severity. While some studies suggest current smokers have reduced susceptibility to SARS-CoV-2 infection but worse outcomes once infected, others report contradictory results. Given these inconsistencies in the literature, this study aimed to clarify the role of smoking in COVID-19 disease severity and outcomes.
METHODS: In this retrospective study, reviewed medical records of patients aged ≥18 years diagnosed with COVID-19 by RT-PCR at St. Luke's Hospital between January 1, 2020, and December 31, 2021. Frequentist and Bayesian multivariable logistic regression was used to assess smoking and COVID-19 outcomes.
RESULTS: Among 1,087 COVID-19 patients, 324 (30%) were former smokers, 162 (15%) were current smokers, and 601 (55%) were non-smokers. No statistically significant differences were observed between smoking groups for severe COVID-19 (p=0.22), ICU admission (p=0.07), acute respiratory failure (p=0.31), or mortality (p=0.15). Former smokers had numerically higher rates of severe COVID-19 (9.9%), ICU admission (1.5%), acute respiratory failure (2.5%), and mortality (4.6%). Multivariable analyses identified age over 65 years, male sex, and obesity as significant risk factors for severity and mortality. Both frequentist and Bayesian analyses showed non-significant trends toward increased severity in current and former versus never smokers. Direct comparisons showed associations with greater severity among current smokers (frequentist OR=1.72, 95% CI: 0.80-3.60; Bayesian OR=1.58, 95% CrI: 0.74-3.34). For mortality, both analyses suggested non-significant trends toward reduced mortality in current smokers (OR=0.99, 95%CI: 0.25-3.22; OR=0.74, 95% CrI: 0.18-2.50).
CONCLUSIONS: This retrospective analysis found no statistically significant differences in severe outcomes between smoking groups, despite former smokers showing numerically higher rates of severe COVID-19, ICU admission, respiratory failure, and mortality. Multivariable analyses identified age over 65 years, male sex, and obesity as significant predictors of poor outcomes, but smoking status was not an independent risk factor in this cohort.
METHODS: In this retrospective study, reviewed medical records of patients aged ≥18 years diagnosed with COVID-19 by RT-PCR at St. Luke's Hospital between January 1, 2020, and December 31, 2021. Frequentist and Bayesian multivariable logistic regression was used to assess smoking and COVID-19 outcomes.
RESULTS: Among 1,087 COVID-19 patients, 324 (30%) were former smokers, 162 (15%) were current smokers, and 601 (55%) were non-smokers. No statistically significant differences were observed between smoking groups for severe COVID-19 (p=0.22), ICU admission (p=0.07), acute respiratory failure (p=0.31), or mortality (p=0.15). Former smokers had numerically higher rates of severe COVID-19 (9.9%), ICU admission (1.5%), acute respiratory failure (2.5%), and mortality (4.6%). Multivariable analyses identified age over 65 years, male sex, and obesity as significant risk factors for severity and mortality. Both frequentist and Bayesian analyses showed non-significant trends toward increased severity in current and former versus never smokers. Direct comparisons showed associations with greater severity among current smokers (frequentist OR=1.72, 95% CI: 0.80-3.60; Bayesian OR=1.58, 95% CrI: 0.74-3.34). For mortality, both analyses suggested non-significant trends toward reduced mortality in current smokers (OR=0.99, 95%CI: 0.25-3.22; OR=0.74, 95% CrI: 0.18-2.50).
CONCLUSIONS: This retrospective analysis found no statistically significant differences in severe outcomes between smoking groups, despite former smokers showing numerically higher rates of severe COVID-19, ICU admission, respiratory failure, and mortality. Multivariable analyses identified age over 65 years, male sex, and obesity as significant predictors of poor outcomes, but smoking status was not an independent risk factor in this cohort.
Conference/Value in Health Info
2026-05, ISPOR 2026, Philadelphia, PA, USA
Value in Health, Volume 29, Issue S6
Code
CO55
Topic
Clinical Outcomes
Topic Subcategory
Clinical Outcomes Assessment, Relating Intermediate to Long-term Outcomes
Disease
SDC: Infectious Disease (non-vaccine), SDC: Respiratory-Related Disorders (Allergy, Asthma, Smoking, Other Respiratory)