Smoking increases the risk of COVID-19 positivity, while Never-smoking reduces the risk

Introduction

Does smoking decrease the risk of testing positive for COVID-19 because the never-smokers (84%) prevalence is high and the current-smokers prevalence is low among COVID-19 positive patients?^1,2,3,4,5,6We sought to determine whether never smoking increases the risk of COVID-19 positivity among the 50 to 69-year old patients because they are more likely to test positive for COVID-19.⁷

Method

We conducted a retrospective chart review of COVID-19 Polymerase chain reaction, in-hospital tested ≥18-year-old patients. A Poisson regression analysis stratified into never-smokers and history of smoking (current + former smokers) was conducted.

Results

277 COVID-19 negative and 117 COVID-19 positive patients’ charts with a never-smokers prevalence of 42.32% and 54% respectively were analyzed. The never-smokers prevalence was 54%, 20-39-years; 61 %, 40 -49-years; 41%, 50 – 69-years; and 43%, 70 – 100-years.

The 40-49-year-old current and former smokers were more likely to test positive for COVID-19 [1.309 (1.047 - 1.635)], unlike the 40-49-year-old never-smokers [0.976 (0.890-1.071)] who had a lower risk.

Regardless of their smoking status, males [1.084(1.021 - 1.151)] and the 50-69-year-old patients [1.082 (1.014 -1.154)] were more likely to test positive for COVID-19, while end stage renal disease [0.908(0.843-0.978)] and non-COVID-19 respiratory viral illness [0.907 (0.863 - 0.953)] patients had a lower risk of COVID-19 positivity.

Heart failure [0.907 (0.830 - 0.991)], chronic obstructive pulmonary disease (COPD) [0.842 (0.745 - 0.952)] and Parkinson’s disease [0.823 (0.708 - 0.957)] never-smokers were less likely to test positive for COVID-19.

Conclusion

This is the first study to show that smoking increases the risk of COVID-19 positivity among the 40-49-year-old patients, while not smoking reduces the risk of COVID-19 positivity among the heart failure, COPD and Parkinson’s disease patients. This study emphasizes that COVID-19 positivity risk is not reduced by smoking and not increased by not smoking.