The Impact of Smoking on the Severity of COVID-19 and Risk Factors for Mortality: A Prospective Study in Hospitalized Patients

Background: Smoking has been linked to an increased risk of contracting many respiratory viral diseases and causes inflammation and damage to the lung epithelium. Smokers were found to have a higher likelihood of presenting with severe COVID-19. Materials and Methods: A 2-year single-center prospective study was conducted at the Pulmonology University Department of Rouiba Hospital. The clinical, biological, and imaging data, along with information on healing, death, or transfers to intensive care, were collected and analyzed for two patient groups: current or former smokers and nonsmokers. Results: There were 482 patients, including 206 men (42.7%), with an average age of 55.2 ± 15.2 years. Smoking tobacco consumption was found in only 14.21% of cases, with patients categorized into two groups: nonsmokers, accounting for 87.6% (422) of the total, and smokers, accounting for 12.4% (60). The smoking group also had a higher percentage of male subjects (93.3% vs. 35.5%) and a greater number of patients with chronic obstructive pulmonary disease (10.0% vs. 0.7%) ( P < 0.0001). In addition, the smoking group had more patients with a history of tuberculosis (6.9% vs. 1.4%) ( P = 0.0076). No difference was found in the duration of hospitalization between the two groups, but admission to intensive care was more common among smokers (16.7%) ( P = 0.02). There were more nonsurvivors among patients who smoked compared to those who did not smoke (4.5% vs. 8.3%), although this difference was not statistically significant ( P = 0.2026). Conclusion: Tobacco and COVID-19 are both factors that attack the lungs by causing inflammation that can surpass the body’s ability to control it. These two culprits can lead to irreversible damage to the respiratory system. Cigarette smokers are more susceptible to SARS-CoV-2 infection and have a higher risk of developing a severe form of COVID-19.