Clinical Presentation and Associated Factors to SARS-CoV-2 infection: A Cross-sectional and Comparative Study Between Smokers and Non-Smokers Population
Main Article Content
Abstract
Introduction: Characterising the symptom profile of COVID-19 in smokers compared to non-smokers enables the identification of distinct clinical patterns and potential risk factors. This, in turn, supports more accurate risk stratification and the formulation of targeted public health strategies, particularly within primary care settings, where early detection and timely intervention are essential.
Material and Methods: A population-based, cross-sectional comparative study was conducted using national surveillance data from 475 healthcare units across Mexico. The analysis focused on patients tested for SARS-CoV-2, stratified by smoking status (smokers and non-smokers). Variables included age, clinical symptoms, comorbidities, test results, and vaccination status. Associations between symptoms, comorbidities, and COVID-19 positivity were assessed using multivariate logistic regression models in both groups.
Results: The study included two groups: a total of 48,314 smokers (12.5%; 95% CI 12.4-12.6) and 338,900 non-smokers patients (87.5%; 95% CI 87.4-87.6), resulting in a total study population of 387,214 patients. From this population, we identified 193,607 patients with COVID-19 (21,777 smokers versus 171,830 non-smokers patients). Smokers exhibited a higher prevalence of all reported symptoms in comparison to non-smokers: headache (62% vs 60.3%), cough (57.7% vs 56.6%), myalgia (42.9% vs 39.7%) and odynophagia (40.4% vs 36.9), with the exception of fever (41.3% vs 43.4%). Signs and symptoms positively associated with a higher likelihood of COVID-19 in both smokers and non-smokers included fever, cough, dyspnoea, chest pain, chills, myalgia, arthralgia, malaise, rhinorrhoea, polypnoea, and cyanosis. In contrast, type 2 diabetes, obesity, and hypertension were linked to an increased risk of COVID-19 only among non-smokers. Age showed an inverse relationship with COVID-19 risk in both groups. Notably, being female was the only factor consistently associated with a higher risk of infection across both populations.
Conclusion: The observed profile among smokers suggests a more symptomatic or severe clinical presentation. The lack of association among obesity, hypertension, and diabetes with COVID-19 in this group suggests a possible existence of distinct biological or behavioural mechanisms influencing disease susceptibility and progression.
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References
2. Xu X, Shi Z, Zhou L, et al. Impact of COVID-19 on risks and deaths of non-communicable diseases in the Western Pacific region. Lancet Reg Health West Pac. 2023;43:100795. Published 2023 Dec 1. doi:10.1016/j.lanwpc.2023.100795
3. Hamer M, Kivimäki M, Gale CR, Batty GD. Lifestyle risk factors, inflammatory mechanisms, and COVID-19 hospitalization: A community-based cohort study of 387,109 adults in UK. Brain Behav Immun. 2020;87:184-187. doi:10.1016/j.bbi.2020.05.059
4. Hernández-Pérez A, García-Gómez L, Rodríguez-Llamazares S, Thirión-Romero I, Osio-Echánove J, Pérez-Padilla R. Associated risks of smoking and possible benefits of cessation in Covid-19: a rapid narrative review. Salud Publica Mex. 2021;63(2, Mar-Abr):262-267. Published 2021 Feb 26. doi:10.21149/9371
5. Umnuaypornlert A, Kanchanasurakit S, Lucero-Prisno DEI, Saokaew S. Smoking and risk of negative outcomes among COVID-19 patients: A systematic review and meta-analysis. Tob Induc Dis. 2021;19:09. Published 2021 Feb 4. doi:10.18332/tid/132411
6. López-Hernández D. Clinical Presentation and Factors Associated to COVID-19 Disease in Mexican Patients. CJAST. 2022,41(1):40-58.
7. Puebla Neira D, Watts A, Seashore J, Polychronopoulou E, Kuo YF, Sharma G. Smoking and risk of COVID-19 hospitalization. Respir Med. 2021;182:106414. doi:10.1016/j.rmed.2021.106414
8. Salehi Z, Motlagh Ghoochani BFN, Hasani Nourian Y, Jamalkandi SA, Ghanei M. The controversial effect of smoking and nicotine in SARS-CoV-2 infection. Allergy Asthma Clin Immunol. 2023;19(1):49. Published 2023 Jun 1. doi:10.1186/s13223-023-00797-0
9. Haddad C, Bou Malhab S, Sacre H, Salameh P. Smoking and COVID-19: A Scoping Review. Tob Use Insights. 2021;14:1179173X21994612. Published 2021 Feb 15. doi:10.1177/1179173X21994612
10. Paleiron N, Mayet A, Marbac V, et al. Impact of Tobacco Smoking on the Risk of COVID-19: A Large Scale Retrospective Cohort Study. Nicotine Tob Res. 2021;23(8):1398-1404. doi:10.1093/ntr/ntab004
11. van Westen-Lagerweij NA, Meijer E, Meeuwsen EG, Chavannes NH, Willemsen MC, Croes EA. Are smokers protected against SARS-CoV-2 infection (COVID-19)? The origins of the myth. NPJ Prim Care Respir Med. 2021;31(1):10. Published 2021 Feb 26. doi:10.1038/s41533-021-00223-1
12. Almazeedi S, Al-Youha S, Jamal MH, et al. Characteristics, risk factors and outcomes among the first consecutive 1096 patients diagnosed with COVID-19 in Kuwait. EClinicalMedicine. 2020;24:100448. Published 2020 Jul 4. doi:10.1016/j.eclinm.2020.100448
13. Torres-Macho J, Ryan P, Valencia J, et al. The PANDEMYC Score. An Easily Applicable and Interpretable Model for Predicting Mortality Associated With COVID-19. J Clin Med. 2020;9(10):3066. Published 2020 Sep 23. doi:10.3390/jcm9103066
14. Strzelak A, Ratajczak A, Adamiec A, Feleszko W. Tobacco Smoke Induces and Alters Immune Responses in the Lung Triggering Inflammation, Allergy, Asthma and Other Lung Diseases: A Mechanistic Review. Int J Environ Res Public Health. 2018;15(5):1033. Published 2018 May 21. doi:10.3390/ijerph15051033
15. Arcavi L, Benowitz NL. Cigarette smoking and infection. Arch Intern Med. 2004;164(20):2206-2216. doi:10.1001/archinte.164.20.2206
16. Bauer CMT, Morissette MC, Stämpfli MR. The influence of cigarette smoking on viral infections: translating bench science to impact COPD pathogenesis and acute exacerbations of COPD clinically. Chest. 2013;143(1):196-206. doi:10.1378/chest.12-0930
17. Bourgonje AR, Abdulle AE, Timens W, et al. Angiotensin-converting enzyme 2 (ACE2), SARS-CoV-2 and the pathophysiology of coronavirus disease 2019 (COVID-19). J Pathol. 2020;251(3):228-248. doi:10.1002/path.5471
18. Beyerstedt S, Casaro EB, Rangel ÉB. COVID-19: angiotensin-converting enzyme 2 (ACE2) expression and tissue susceptibility to SARS-CoV-2 infection. Eur J Clin Microbiol Infect Dis. 2021;40(5):905-919. doi:10.1007/s10096-020-04138-6
19. Leung JM, Yang CX, Tam A, et al. ACE-2 expression in the small airway epithelia of smokers and COPD patients: implications for COVID-19. Eur Respir J. 2020;55(5):2000688. Published 2020 May 14. doi:10.1183/13993003.00688-2020
20. Pan M, Yu M, Zheng S, Luo L, Zhang J, Wu J. Genetic variations in ACE2 gene associated with metabolic syndrome in southern China: a case-control study. Sci Rep. 2024;14(1):10505. Published 2024 May 7. doi:10.1038/s41598-024-61254-5
21. Pinheiro DS, Santos RS, Jardim PCBV, et al. The combination of ACE I/D and ACE2 G8790A polymorphisms revels susceptibility to hypertension: A genetic association study in Brazilian patients. PLoS One. 2019;14(8):e0221248. Published 2019 Aug 20. doi:10.1371/journal.pone.0221248