The Role of Smoking on Incidence and Prognosis of Covid-19 Patients Admitted to Tishreen University Hospital

Background: In February 2020, the World Health Organization identified Covid-19 and identified SARAS-COV2as the cause of the disease. So far, the number of infected people has exceeded 633 million, while the death toll hasexceeded 6.6 million. Since the start of the pandemic, there have been conflicting reports about smoking in termsof incidence and prognosis.Objective: The aim of this study was to investigate the effect of smoking on incidence and prognosis of COVID-19patients.Patients and Methods: An Analytic Observational Cohort study was conducted in patients with a proven diagnosisof COVID-19. They are selected from Pulmonary Medicine department, Tishreen University Hospital in Lattakia-Syria between June 2020 and December 2020. Study population were divided into two groups according to thepatient’s smoking status; group I included smoker (237 cases), and group II included non-smoker (277 cases).Results: The population of 514 patients was predominantly male (66.1%), with a mean age of 61.76±14.9 years.46.1% of the patients were smoker with presence of associated chronic diseases in 341 cases (66.3%). There wereno significant differences between two groups regarding gender and comorbidities (p>0.05). Patients weresignificantly older in group I than in group II (71.22±13.2 versus 60.88±15.2, p:0.001). The rate of oxygen-basedtreatment was higher in smokers compared non-smokers (84.8% versus 67.9%, p:0.03). Non-invasive mechanicalventilation was necessary in 31 patients (13.1%) in group I versus 73 patients (26.4%) in group II, p:0.04. Theduration of hospitalization was longer in non-smoker group (7.2±4.1 versus 5.7±3.9, p:0.001). Recovery rate washigher in non-smoker patients (81.2% versus 68.4%). In addition to, 75 patients (31.6%) in smoker group diedversus 52 patients (18.8%) in non-smoker group, p: 0.005. Conclusion: The current study demonstrated presence of favorable inverse associations of smoking with durationof hospitalization and the need to non-invasive mechanical ventilation in COVID-19 patients.