SynthesisHarm reduction journal2021
Smoking prevalence among hospitalized COVID-19 patients and its association with disease severity and mortality: an expanded re-analysis of a recent publication.
Synthesis in Harm reduction journal, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
33 citing papers in PubMed, 61 citations in OpenAlex.
- Tobacco smoking and severity of COVID-19: Experience from a hospital-based prospective cohort study in Lyon, France.Journal of medical virology · 2021Trial
- Cigarette smoking history, e-cigarette use, and Long COVID: a population-based analysis.Internal and emergency medicine · 2026Article
- Severe COVID-19 in Non-Smokers: Predictive Factors and Outcomes.Healthcare (Basel, Switzerland) · 2025Article
- Impact of Smoking and Deprivation in Patients Admitted With Severe COVID-19 Infection to ICU: A Retrospective Cohort Study.Interdisciplinary perspectives on infectious diseases · 2025Article
- Cigarette smoking status and COVID-19 hospitalization in the context of cannabis use: An electronic health record cohort study in northern California.Addictive behaviors reports · 2024Article
- Associations between lifestyle factors and COVID-19 infection rates: a cross-sectional analysis in the USA.BMJ public health · 2024Article
- Looking at the Data on Smoking and Post-COVID-19 Syndrome-A Literature Review.Journal of personalized medicine · 2024Review
- Prevalence and risk factors of SARS-CoV-2 antibody responses among healthcare workers (June 2020-November 2021).European journal of public health · 2023Observational
- Risk factors and characteristics of hospitalized COVID-19 patients in Jordan.Saudi medical journal · 2023Article
- The predisposition of smokers to COVID-19 infection: A mini-review of global perspectives.Heliyon · 2023Review
- The controversial effect of smoking and nicotine in SARS-CoV-2 infection.Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology · 2023Review
- New insights into how popular electronic cigarette aerosols and aerosol constituents affect SARS-CoV-2 infection of human bronchial epithelial cells.Scientific reports · 2023Article
- The SARS-CoV-2 Virus and the Cholinergic System: Spike Protein Interaction with Human Nicotinic Acetylcholine Receptors and the Nicotinic Agonist Varenicline.International journal of molecular sciences · 2023Article
- Association of combustible cigarettes and heated tobacco products use with SARS-CoV-2 infection and severe COVID-19 in Japan: a JASTIS 2022 cross-sectional study.Scientific reports · 2023Article
- Tobacco Smoking and Risk of SARS-CoV-2 Infection and Disease Severity Among Adults in an Integrated Healthcare System in California.Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco · 2023Article
- Patients' characteristics and 30-day mortality for those undergoing elective surgeries during the COVID-19 pandemic in Bangladesh.PloS one · 2023Article
- Utility of NO and HNitric oxide : biology and chemistry · 2022Review
- Quantum tunnelling in the context of SARS-CoV-2 infection.Scientific reports · 2022Article
- New Insights into How JUUL™ Electronic Cigarette Aerosols and Aerosol Constituents Affect SARS-CoV-2 Infection of Human Bronchial Epithelial Cells.bioRxiv : the preprint server for biology · 2022Article
- Can smoking prevalence explain COVID-19 indicators (cases, mortality, and recovery)? A comparative study in OECD countries.Environmental science and pollution research international · 2022Article
Corrections and comments
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Authors and funding
6 authors at 5 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThere is a lot of debate about the effects of smoking on COVID-19. A recent fixed-effects meta-analysis found smoking to be associated with disease severity among hospitalized patients, but other studies report an unusually low prevalence of smoking among hospitalized patients. The purpose of this study was to expand the analysis by calculating the prevalence odds ratio (POR) of smoking among hospitalized COVID-19 patients, while the association between smoking and disease severity and mortality was examined by random-effects meta-analyses considering the highly heterogeneous study populations.
methodsThe same studies as examined in the previous meta-analysis were analyzed (N = 22, 20 studies from China and 2 from USA). The POR relative to the expected smoking prevalence was calculated using gender and age-adjusted population smoking rates. Random-effects meta-analyses were used for all other associations.
resultsA total of 7162 patients were included, with 482 being smokers. The POR was 0.24 (95%CI 0.19-0.30). Unlike the original study, the association between smoking and disease severity was not statistically significant using random-effects meta-analysis (OR 1.40, 95%CI 0.98-1.98). In agreement with the original study, no statistically significant association was found between smoking and mortality (OR 1.86, 95%CI 0.88-3.94).
conclusionAn unusually low prevalence of smoking, approximately 1/4th the expected prevalence, was observed among hospitalized COVID-19 patients. Any association between smoking and COVID-19 severity cannot be generalized but should refer to the seemingly low proportion of smokers who develop severe COVID-19 that requires hospitalization. Smokers should be advised to quit due to long-term health risks, but pharmaceutical nicotine or other nicotinic cholinergic agonists should be explored as potential therapeutic options, based on a recently presented hypothesis.
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