Smoking Prevalence among Severe and Critical Cases of COVID 19 Patients in Sulaimani/ Single Center Study


  • Bakhtyar Qadr Hama Khurshid ( MBCHB, FKBMS ) Department of critical care medicine, Shar Teaching Hospital/ Sulaymaniyah/ Iraq
  • Haval Othman Ali ( MBCHB, CABD, FIBMS ) Department of Critical Care Medicine, Shar Teaching Hospital, Sulaymaniyah, Iraq


COVID-19, Smoking, Mortality


Background and Objectives: Smoking is a known risk factor for various respiratory infections and
diseases. However, its impact on the severity and outcomes of COVID-19 remains a subject of
ongoing research. The objective is to evaluate if smoking is linked to mortality in COVID-19
Methods: A retrospective cohort study was conducted on the ICU admitted COVID-19 patients,
between May, 2020 and July, 2021. Admitted patients to the hospital with positive Severe acute
respiratory sendrom-2 were categorized based on smoking status. The main focus was on mortality
during hospitalization. Odds ratios (OR) and 95% confidence intervals (95%CI) were presented for
smoking status.
Results: Among 400 COVID-19 deaths (mean age was 61.2 ± 13.0 years), the majority was
between 60-60 years (35.3%, n=141), followed by older than 70 years (27.7%, n=111) then 50-59
years (17.7%, n=71), then 40-49 years (12.3%, n=49), only 7.0% (n=28) was < 40 years. The
majority was male (62.2%, n=249) rather than female (37.8%, n=151). Mean ICU stay was 9.3 ±
10.7 days. 59.5% have at least one comorbidity. The prevalence of active smoker =1.8% vs 5.3%;
former smoker= 28.7% vs 22.1%; and never smoker= 69.5% vs 72.5% regarding death and
discharged patients. AS has lower risk of mortality (OR= 0.36 (95%CI 0.13- 0.99; P =0.041) than
NS, The AS, as well as low risk of mortality (OR=0.29 (95%CI 0.11- 0.79; P = 0.0) than FS.
Indeed, the former smoker has higher risk mortality (OR was 1.25 (95%CI 0.88 - 1.78; P= 0.203)
than NS.
Conclusion: The older adults, males, comorbidity are at higher mortality risk by COVID-19
infection. Active smokers have lower in-ICU mortality than former smokers and never smokers,
While, the former smokers have higher risk of mortality than active smokers and never smokers.


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