Association between the clinical presentation and outcome among smokers vs non- smokers COVID-19 patients in Kirkuk health care centers/Iraq

Background: Smoking is regarded as one of the most important reasons of diseases and lead to eight million deaths all over the world. Both factors including corona virus disease 2019 (COVID-19) infection related to smoking can primarily affect the lungs. COVID-19 is mainly transmitted through the respiratory tract (saliva), and the smoker group may be at a higher risk of contracting the virus because of impaired immune systems, reduced lung function, susceptible hygiene habits, and cross-infection. Objectives: The study aimed to determine if there is any association between the current smoking and the clinical severity and outcomes of disease among patients suffering from COVID-19 in Kirkuk city. Materials and Methods: Retrospective case series include 973 adult (≥18 years old) patients (525 male and 448 female) with confirmed COVID-19. The studied patients were diagnosed by reverse transcriptase-polymerase chain reaction (PCR) by taking a swab from a nasopharyngeal region during the period from July 2020 to October 31, 2021. The data were collected from patients on the first visit to health services system (Private Clinic, AL-shifaa Hospital, and Kirkuk General Hospital). The diagnosis of patients with COVID-19 pneumonia was based on symptoms. Presence of infiltration on chest X-ray or high-resolution CT scan with positive PCR swab for SARS-CoV-2 was found. The total number of patients included in the study was 974 (646 smokers and 328 non-smokers). A special questionnaire form was prepared for this purpose and distributed after receiving the verbal consent from them, and the data were collected by interviewing with them. Results: This study shows that the most affected age group between smokers and non-smokers was 50–59 years (47.35%–49.8%), respectively, with P value = 0.444. Regarding the sex, males from smoker group constitute a higher percentage (75.6%), in comparison to non-smoker group in which the females constitute a higher percent (56.2%) with a P -value = 0.000. Also the study reveals that the smoker group shows a high percent among patients with hypertension (33.8%), in comparison to the non-smoker group in which diabetes mellitus was the most comorbid disease (37.9%) with a P -value = 0.000. Conclusion: The study recommended that physicians can provide more attention to the smoking history in patients with COVID-19 infection, and more future advanced research is aimed to explain the mechanisms that decrease this risk.