Systematic review of the prevalence of current smoking among hospitalized COVID-19 patients in China: could nicotine be a therapeutic option?
Open Access
- 9 May 2020
- journal article
- review article
- Published by Springer Science and Business Media LLC in Internal and Emergency Medicine
- Vol. 15 (5), 845-852
- https://doi.org/10.1007/s11739-020-02355-7
Abstract
The effects of smoking on Corona Virus Disease 2019 (COVID-19) are currently unknown. The purpose of this study was to systematically examine the prevalence of current smoking among hospitalized patients with COVID-19 in China, considering the high-population smoking prevalence in China (26.6%). A systematic review of the literature (PubMed) was performed on April 1. Thirteen studies examining the clinical characteristics of hospitalized COVID-19 patients in China and presenting data on the smoking status were found. The pooled prevalence of current smoking from all studies was calculated by random-effect meta-analysis. To address the possibility that some smokers had quit shortly before hospitalization and were classified as former smokers on admission to the hospital, we performed a secondary analysis in which all former smokers were classified as current smokers. A total of 5960 patients were included in the studies identified. The current smoking prevalence ranged from 1.4% (95% CI 0.0–3.4%) to 12.6% (95% CI 10.6–14.6%). An unusually low prevalence of current smoking was observed from the pooled analysis (6.5%, 95% CI 4.9–8.2%) as compared to population smoking prevalence in China. The secondary analysis, classifying former smokers as current smokers, found a pooled estimate of 7.3% (95% CI 5.7–8.9%). In conclusion, an unexpectedly low prevalence of current smoking was observed among patients with COVID-19 in China, which was approximately 1/4th the population smoking prevalence. Although the generalized advice to quit smoking as a measure to reduce health risk remains valid, the findings, together with the well-established immunomodulatory effects of nicotine, suggest that pharmaceutical nicotine should be considered as a potential treatment option in COVID-19.This publication has 70 references indexed in Scilit:
- Replication-dependent downregulation of cellular angiotensin-converting enzyme 2 protein expression by human coronavirus NL63Journal of General Virology, 2012
- Nicotine treatment of mild cognitive impairmentNeurology, 2012
- Nicotine Exerts an Anti-inflammatory Effect in a Murine Model of Acute Lung InjuryInflammation, 2010
- The discovery of angiotensin‐converting enzyme 2 and its role in acute lung injury in miceExperimental Physiology, 2008
- Chronic high dose transdermal nicotine in Parkinson's disease: an open trialEuropean Journal of Neurology, 2007
- The alpha7 nicotinic acetylcholine receptor as a pharmacological target for inflammationBritish Journal of Pharmacology, 2007
- Physiology and immunology of the cholinergic antiinflammatory pathwayJCI Insight, 2007
- Nicotine exposure alters in vivo human responses to endotoxinClinical and Experimental Immunology, 2006
- Nicotinic acetylcholine receptor α7 subunit is an essential regulator of inflammationNature, 2002
- Transdermal Nicotine for Active Ulcerative ColitisThe New England Journal of Medicine, 1994