Smoking is Associated with Higher Mortality and Hospitalization Secondary to Novel Coronavirus: A Systematic Review

Aim: The aim of the present study was to assess whether there is an association between smoking and higher mortality and hospitalization due to the disease of the new coronavirus (COVID-19). Methods: A systematic review of studies on the novel coronavirus containing information on smoking and its association with COVID-19 mortality was carried out. The bibliographic search was performed using six databases, with the search terms: ['novel coronavirus' OR ‘COVID- 19'] AND ['smoking' OR ‘tobacco'] AND ['mortality']. Studies published from December 2019 until April 8, 2020 were included. As an inclusion criterion, studies targeting humans, adults, infected with Sars-Cov-2 were selected, and as the chosen language, English. Results: From the total of researched studies, 65 articles were selected, one being presented in two databases simultaneously. As a final result of this review, 11 articles were included, with a population total estimated at 84.050 patients, with the prevalence of smokers ranged from 1.4% to 27.3% and it was observed that the impact of smoking on fatal outcomes was described in four publications, with unfavourable repercussions on hospitalization rates and more serious conditions secondary to COVID-19 (9 out of the 11 publications evaluated). Conclusion: The presence of smoking can worsen infectious conditions by COVID-19 and increase the prevalence of hospitalizations and fatal outcomes, especially in men, the elderly and those with multimorbidities. Smoking status should be used in the screening of patients infected with the novel coronavirus given the evidence of poorer outcomes among smokers.