Observational studyThorax2022
Smoking and COVID-19 outcomes: an observational and Mendelian randomisation study using the UK Biobank cohort.
Observational study in Thorax, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 109 papers, 6 of them syntheses that pooled it.
What it found
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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.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
109 citing papers in PubMed, 6 syntheses or guidelines pooled it.
- Impact of COVID-19 lockdown on smoking and vaping: systematic review and meta-analysis.Public health · 2023Pooled it
- The role of smoking in COVID-19 progression: a comprehensive meta-analysis.European respiratory review : an official journal of the European Respiratory Society · 2023Pooled it
- Pulmonary function and chest computed tomography abnormalities 6-12 months after recovery from COVID-19: a systematic review and meta-analysis.Respiratory research · 2022Pooled it
- Identifying factors contributing to increased susceptibility to COVID-19 risk: a systematic review of Mendelian randomization studies.International journal of epidemiology · 2022Pooled it
- Changes in Diet, Physical Activity, Alcohol Consumption, and Tobacco Use in Adults During the COVID-19 Pandemic: A Systematic Review.Inquiry : a journal of medical care organization, provision and financingPooled it
- Sex Differences and Clinical Outcomes of Patients with Coronavirus Disease 2019 Infection and Cerebral Venous Sinus Thrombosis: A Systematic Review.Clinical and applied thrombosis/hemostasis : official journal of the International Academy of Clinical and Applied Thrombosis/HemostasisPooled it
- Immediate smoking cessation support versus usual care in smokers attending a targeted lung health check: the QuLIT trial.BMJ open respiratory research · 2022Trial
- HPV vaccination intention among unvaccinated international and domestic college students in the U.S.: A cross-sectional survey.Human vaccines & immunotherapeutics · 2026Article
- Article
- Bidirectional causal association between cathepsins and neuropsychiatric disorders: univariate and multivariate Mendelian randomization study.European archives of psychiatry and clinical neuroscience · 2026Article
- Review
- Gastroesophageal reflux disease and childhood asthma: A bidirectional two-sample Mendelian randomization study.Medicine · 2026Article
- Inequality in life expectancy losses by education in Finland during COVID-19 pandemic.International journal for equity in health · 2026Article
- Cigarette smoking and SARS-CoV-2 infection: multivariable regression and Mendelian randomization analyses in the Norwegian Mother, Father and Child Cohort Study.BMC infectious diseases · 2026Article
- Nicotine dependence among critically ill COVID-19 patients: A population-based cohort study.PloS one · 2026Article
- The association between smoking and COVID-19 symptoms, severity, and post-COVID-19 symptoms: a cross-sectional survey study.Frontiers in public health · 2026Article
- Five years of discourse related to Indonesia tobacco control reform: a content analysis of online media coverage.Tobacco control · 2025Article
- Smoking status and the onset of suicidal ideation among adults in Japan during the COVID-19 pandemic.Annals of general psychiatry · 2025Article
- Lung cancer and COVID-19 susceptibility and severity: a Mendelian randomization analysis.BMC cancer · 2025Article
- Impact of the COVID-19 Pandemic on Changes in Tobacco Use Behavior: A Longitudinal Cohort Study in Japan.Journal of epidemiology · 2025Article
49 more citing papers are in PubMed but not listed here.
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Authors and funding
10 authors.
Funding
Abstract
backgroundConflicting evidence has emerged regarding the relevance of smoking on risk of COVID-19 and its severity.
methodsWe undertook large-scale observational and Mendelian randomisation (MR) analyses using UK Biobank. Most recent smoking status was determined from primary care records (70.8%) and UK Biobank questionnaire data (29.2%). COVID-19 outcomes were derived from Public Health England SARS-CoV-2 testing data, hospital admissions data, and death certificates (until 18 August 2020). Logistic regression was used to estimate associations between smoking status and confirmed SARS-CoV-2 infection, COVID-19-related hospitalisation, and COVID-19-related death. Inverse variance-weighted MR analyses using established genetic instruments for smoking initiation and smoking heaviness were undertaken (reported per SD increase).
resultsThere were 421 469 eligible participants, 1649 confirmed infections, 968 COVID-19-related hospitalisations and 444 COVID-19-related deaths. Compared with never-smokers, current smokers had higher risks of hospitalisation (OR 1.80, 95% CI 1.26 to 2.29) and mortality (smoking 1-9/day: OR 2.14, 95% CI 0.87 to 5.24; 10-19/day: OR 5.91, 95% CI 3.66 to 9.54; 20+/day: OR 6.11, 95% CI 3.59 to 10.42). In MR analyses of 281 105 White British participants, genetically predicted propensity to initiate smoking was associated with higher risks of infection (OR 1.45, 95% CI 1.10 to 1.91) and hospitalisation (OR 1.60, 95% CI 1.13 to 2.27). Genetically predicted higher number of cigarettes smoked per day was associated with higher risks of all outcomes (infection OR 2.51, 95% CI 1.20 to 5.24; hospitalisation OR 5.08, 95% CI 2.04 to 12.66; and death OR 10.02, 95% CI 2.53 to 39.72).
interpretationCongruent results from two analytical approaches support a causal effect of smoking on risk of severe COVID-19.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.