- Smokers are more susceptible to the most recent species of Coronavirus infections3,5.
- History of smoking may also impact disease progression1,3.
- Smokers were 1.4 times more prone to develop severe symptoms1.
- They also had 2.4 times greater likelihood to be admitted to the ICU, need mechanical ventilation or die1.
- Current smokers have a significantly higher ACE-2 gene expression levels than non-smokers2,5,6.
- Suggesting an increased risk for viral binding and entry of SARS-CoV-2 in lungs of smokers6.
- Smokers could have unregulated ACE2 in remodeled cell types3.
- Those findings were quite evident in the type-2 pneumocytes, alveolar macrophages and the apical end of the small airway epithelium5.
- This could also be found with patients who are using new electronic smoking devices. Further researches on these products are needed5.
This data comes 6 articles. Constantine I., et al present a systematic review where 5 retrospective and prospective studies conducted in China were included. They studied how smoking would affect the severity of the disease. Hua Cai present an analysis of 5 different Chinese studies. They wanted to explore if there were some predispositions to COVID-19 depending on the sex of patients and if they were smokers. Emami A., et al have written a meta-analysis to estimate the prevalence of underlying disease with confirmed and hospitalized COVID-19 patients. 3403 cases have been used for the analysis. Leung JM., et al present a Research letter to determine if patients with COPD have increased expression of ACE-2 which is the cellular entry receptor for SARS-CoV-2. Brake SJ., et al present an Editorial to investigate if smoking, smoking-induced health conditions and comorbidities are high risk for contracting the virus and to develop severe presentation of Covid-19. Cai G., et al present a comprehensive set of transcriptomic datasets to investigate the associations between smoking and ACE2, FURIN and TMPRSS2 gene expression.
- Constantine l. Vardavas, Katerina Nikitara. (March 20th, 2020). COVID-19 and smoking: A systematic review of the evidence. Tobacco Induced Diseases. DOI: https://doi.org/10.18332/tid/119324
- Hua Cai (March 11, 2020). Sex difference and smoking predisposition in patient with COVID-19. The Lancet, respiratory Medicine. DOI: 1016/S2213-2600(20)30117-X
- Emami A., Javanmardi F., Pirbonyeh N., et al. (March 24, 2020). Prevalence of Underlying Diseases in Hospitalized Patients with COVID-19: a Systematic Review and Meta-Analysis. Archive of Academics Emergency Medicine. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7096724/
- Leung JM., Yang CX., Tam A., et al. (April 8, 2020). ACE-2 Expression in the Small Airway Epithelia of Smokers and COPD Patients: Implications for COVID-19. European Respiratory journal. DOI:1183/13993003.00688-2020
- Brake SJ., Barnsley K., Lu W., et al. (March 18, 2020). Smoking Upregulates Angiotensin-Converting Enzyme-2 Receptor: A Potential Adhesion Site for novel Coronavirus SARS-CoV-2 (Covid-19). Journal of Clinical Medicine, MDPI. DOI:https://doi.org/10.3390/jcm9030841
- Cai G., Bossé Y., Xiao F., et al. (April 24, 2020). Tobacco Smoking Increases the Lung Gene Expression of ACE2, the Receptor of SARS-CoV-2. American Journal of Respiratory and Critical Care Medicine. https://doi.org/10.1164/rccm.202003-0693LE