UK: Smoking may be linked to higher risk of COVID-19 infection

A study by the Department of Behavioural Science and Health, University College London, shows that current smokers have a higher risk of being infected with COVID-19 than non-smokers, and that this risk is higher among smokers from lower socioeconomic classes.[1]Paradoxically, smokers' compliance with health recommendations is lower than that of non-smokers, even though they are more afraid of being infected with Covid-19 and becoming more seriously ill.

Method :

This cross-sectional study, based on longitudinal online monitoring of a cohort of 53,002 adults (aged 18 and over, with a good representation of different socioeconomic groups in the UK), focused on: tobacco consumption, socioeconomic status, health status, confirmed or suspected COVID-19 infection, fear of being infected with the Covid-19 virus and developing a severe form of the disease, compliance with preventive measures, and possible recent change in smoking. As this was a non-randomized sample, the data were weighted according to age, sex, ethnicity, education level, and place of residence.

Results :

Overall, the prevalence of confirmed COVID-19 infection among ex-smokers was no different from that of never-smokers, while it was 1.8 times higher among current smokers. Moreover, among current smokers with the lowest socioeconomic status, this prevalence was 3.5 times higher than among non-smokers.

Current smokers and ex-smokers reported being stressed about contracting Covid-19 more frequently than never-smokers (x 1.34 and x 1.22, respectively). This fear was higher among current smokers with the lowest socioeconomic levels. Similarly, the fear of developing a severe form of the disease was more prevalent among current smokers (approximately 30%) than among never-smokers (approximately 20%).

About 96 % of all respondents reported observing protective measures against virus transmission; this % was slightly lower among current smokers, and particularly among unqualified current smokers.

Finally, changes in current smokers' tobacco consumption related to COVID-19 were independent of their socioeconomic status: 44% did not change it, 42% increased it, and 13% decreased it.

Conclusion :

This large-scale study does not confirm previously published observations suggesting a lower rate of COVID-19 infection among current smokers. Further research is therefore needed before any conclusions can be drawn about whether smoking status has a protective or debilitating effect on the risk of contracting COVID-19.