Note: I have added a second paper ref below too.
This is a thought provoking paper/editorial in Toxicology Reports by Elsevier (and a paper which is cited by 19 other studyies/papers) and is one of many being published related to how lower rates of serious cases of CV19 are being seen among smokers. I have long wondered what the move against smoking was about, which really began around 2005-10 in earnest - in terms of many Western govs mandating anti-smoking measures which would end up lower their tax revenue raised on sales of cigarettes (i.e. not typical/expected gov behavior). Before seeing such papers as this one, I had been presuming it was linked to the atmospheric aerosol engineering projects, i.e. that maybe the extra layer of phlegm which smoking tends to produce in the throat, etc, hindered the uptake of aerosol particulates. That may well have been part of the reason, but this current hypothesis to do with CV19 seems more likely now imo. Also to note, some Spanish and South African states banned cigarette sales during a period of the first main lockdown - see here.
Some quotes from the paper (out of order):
7. Conclusions
In conclusion, we noticed that most of the clinical characteristics of severe COVID-19 could be explained by dysregulation of the cholinergic anti-inflammatory pathway. The observation that patients eventually develop cytokine storm which results in rapid clinical deterioration, led to the development of a hypothesis about the series of events associated with adverse outcomes in COVID-19 (Fig. 2).
6. Nicotine as a potential treatment for COVID-19
Nicotine could act as a competitive agonist for the nAChRs that could restore the compromised function of the nicotinic cholinergic system. This may be feasible through repurposing already approved (for other indications) pharmaceutical nicotine products such as nicotine patches for use by non-smokers, or even by using these products as already indicated (i.e. as smoking substitutes) among current smokers. These products are available over-the-counter in most countries. They have been administered therapeutically in non-smokers for neurological conditions and inflammatory bowel disease for larger periods than would be needed for COVID-19 [[83], [84], [85]]. No abuse liability was observed in non-smokers despite being administerd for several weeks [84,85]. Besides gums and patches, nicotine can be administered though inhalation, with the use of a nebulizer or other aerosol systems, if necessary. Nicotine administration could be added on top of antiviral or other therapeutic options for COVID-19. By restoring and re-activating the cholinergic anti-inflammatory pathway, a more universal suppression of the cytokine storm could probably be achieved compared to administering inhibitors of a single cytokine. The potential need to provide pharmaceutical nicotine products to smokers and users of other nicotine products who experience abrupt nicotine cessation when hospitalized for COVID-19 or aim to follow medical advice to quit smoking, should also be examined. If the hypothesis about the beneficial effects of nicotine is valid, smokers who quit nicotine use when hospitalized will be deprived from these benefits. In France, the Addiction Prevention Network (RESPADD) officially recommends the use of nicotine replacement therapies for smokers when hospitalized for any illness [86]. Clinical trials will dictate future approaches and the role of nicotine in COVID-19, while further experimental studies should examine the affinity of the virus to nAChRs.
The full paper is as follows and available at the link below:
Editorial: Nicotine and SARS-CoV-2: COVID-19 may be a disease of the nicotinic cholinergic system
https://www.sciencedirect.com/science/article/pii/S2214750020302924
doi: 10.1016/j.toxrep.2020.04.012
The second paper is titled:
Low incidence of daily active tobacco smoking in patients with symptomatic COVID-19
https://www.qeios.com/read/WPP19W.3
doi: 10.32388/WPP19W.3
The abstract reads as follows:
Importance: As the pandemic of COVID-19 is still under progression, identification of prognostic factors remains a global challenge. The role of cigarette smoking has been suggested among the disease’s epidemiological risk factors, although it is highly controversial.
Objective: To evaluate the correlation of daily smoking with the susceptibility to develop SARS-CoV-2 infection.
Participants: We estimated the rates of daily current smokers in COVID-19-infected patients in a large French university hospital between February 28th , 2020 and March 30th , 2020 for outpatients and from March 23rd , till April 9th , 2020 for inpatients.
Design: The rates from both groups were compared to those of daily current smokers in the 2018 French general population, established in 2018, after standardization of the data for sex and age.Results: The inpatient group was composed of 343 patients, median age 65 yr: 206 men (601%, median age 66 years) and 137 women (39.9%, median age 65 years) with a rate of daily smokers of 4.4% (5.4% of men and 2.9% of women).The outpatient group was composed of 139 patients, median age 44 years: 62 men (44.6 %, median age 43 years, and 77 women (55.4 %, median age 44 years). The daily smokers rate was 5.3% (5.1% of men and 5.5 % of women). In the French population, the daily smokers rate was 25.4% (28.2% of men and 22.9% of women).
The rate of current daily smokers was significantly lower in COVID-19 outpatients and inpatients (80.3% and 75.4%, respectively), as compared to that in the French general population with standardized incidence ratios according to sex and age of 0.197 [0.094 - 0.41] and 0.246 [0.148 - 0.408]. These ratios did not significantly differ between the two groups (P=0.63).
Conclusions and relevance: Our cross sectional study in both COVID-19 out- and inpatients strongly suggests that daily smokers have a very much lower probability of developing symptomatic or severe SARS-CoV-2 infection as compared to the general population.
