What are the possible relations between tobacco use and the COVID19 epidemic?

Any kind of tobacco smoking is harmful to the bodily systems, including the cardiovascular and respiratory systems [1] [2]. COVID-19 can also harm these systems. Information from China, where COVID-19 originated, shows that people who have cardiovascular and respiratory conditions caused by tobacco use, or otherwise, are at higher risk of developing severe COVID-19 symptoms [3]. Research on 55,924 laboratory confirmed cases in China shows that the crude fatality ratio for COVID-19 patients is much higher among those with cardiovascular disease, diabetes, hypertension, chronic respiratory disease or cancer than those with no pre-existing chronic medical conditions [4]. This demonstrates that these pre-existing conditions may contribute to increasing the susceptibility of such individuals to Covid-19.

Tobacco has a huge impact on respiratory health. The link between tobacco use and lung cancer is well-established, with tobacco use being the most common cause of lung cancer [5]. It also substantially increases the risk of tuberculosis infection [6]. Further, tobacco use is also the most important risk-factor for chronic obstructive pulmonary disease (COPD), causing the swelling and rupturing of the air sacs in the lungs, which reduces the lung’s capacity to take in oxygen and expel carbon dioxide, and the build-up of mucus, which results in painful coughing and breathing difficulties [7] [8] [9]. This may have implications for smokers, given that smoking is considered to be a risk factor for any lower respiratory tract infection [10] and the virus that causes COVID-19 primarily affects the respiratory system, often causing mild to severe respiratory damage [4]. However, given that COVID-19 is a newly identified disease, the link between tobacco smoking and the disease has yet to be established.

There is an increased risk of more serious symptoms and death among COVID-19 patients that have underlying cardiovascular diseases (CVDs) [11] [12]. According to the available evidence the virus that causes COVID-19 (SARS-CoV-2) is from the same family as MERS-CoV and SARS-CoV, both of which have been associated with cardiovascular damage (either acute or chronic) [13] [14]. Research has shown COVID-19 patients in China with CVDs are at greater risk of more severe symptoms [15] In addition, there is evidence that COVID-19 patients that have more severe symptoms often have heart related complications [16]. This relation between COVID-19 and cardiovascular health is important because tobacco use and exposure to second-hand smoke are major causes of CVDs globally [17]. The effect of COVID-19 on the cardiovascular system could thus make pre-existing cardiovascular conditions worse. In addition, a weaker cardiovascular system among COVID-19 patients with a history of tobacco use could make such patients susceptible to severe symptoms, thereby increasing the chance of death [18].