Introduction:

The relation between smoking and the severity of COVID-19 infection has been evoked in the literature. The results are controversial and no conclusions have been drawn regarding this association.

The aim is to study the relation between smoking and the severity of COVID-19 infection

Methods:

This is a retrospective, comparative and analytical study, including 100 patients hospitalized in our pulmonology department for COVID-19 from October 2020 to January 2021.

Patients (P) were divided into two groups: Group 1 (G1): 35 P who are active or weaning off tobacco for less than 6 months, and Group 2 (G2): 65 P who had not smoked or weaned off for more than 6 months

Results:

There was no significant difference in the average age(62.1:G1 vs. 62.83:G2,p=0.39). A male predominance was noted in G1 (94.3% vs. 44.6%, p<0.001). Comorbidities were associated in 72%, presented mainly by high blood pressure(37%) diabetes(32%) and obesity(19%) with no statistical difference between the two groups.  Severe clinical presentations were more frequent in G1(OR=3.963, 95%CI: 0.752-9.561, p=0.042). More frequent use of high-flow oxygen therapy and non-invasive ventilation was noted in G1(14.3% vs. 1.5%, p=0.01).  Transfer to intensive care unit was more common in G1 (OR=6.921, 95%CI: 2.139-11.308, p=0.027). CT presentation was more severe in smokers(OR=5.014, 95%CI: 3.380-9.102, p=0.012)

The multivariate analysis with clinical severity as a dependent variable, finds smoking, male sex and comorbidities as independent factors

No significant differences in the duration of hospitalization or mortality were identified between the two groups (p=0.6 vs p=0.716)

Conclusion

Our study highlighted the role of smoking in development of a severe form of COVID-19 disease.