Smokers more vulnerable to die from COVID-19?

Mbabane: As the deadly coronavirus continue to spread incessantly across the globe, inconclusive available evidence suggest that smokers are susceptible to die from the disease as smoking is associated with increased severity of the disease and death in hospitalized COVID-19 patients.

This indecisive conclusion was also reached by the World Health Organisation (WHO) when making an assessment of available peer-reviewed literature on the association between smoking and COVID-19, including 1) risk of infection by SARS-CoV-2; 2) hospitalisation with COVID19; and 3) severity of COVID-19 outcomes among hospitalized patients such as admission into intensive care units (ICU), use of ventilators and death.

 In the COVID-19 pandemic, questions have been asked about clinical outcomes for smokers, and whether they are equally susceptible to infection, and if nicotine has any biological effect on the SAR-CoV-2 virus (the virus that causes COVID-19).

 

Review of the evidence

According to WHO’s Scientific brief on Smoking and COVID-19, 35 peer-reviewed studies met the inclusion criteria. All included studies were in English. None examined tobacco use and the risk of infection or the risk of hospitalization. The brief says a total of 27 observational studies and eight meta-analyses were identified. All observational studies reported the prevalence of smoking amongst hospitalized COVID-19 patients.

Nineteen of the 27 observational studies containing data on smoking status by severity of COVID-19 outcomes. Six meta-analyses were identified that examined the association between smoking and severity of COVID-19. The WHO went on to detail that nine (9) of the 19 studies were included in the six meta-analyses of smoking and severity (five to seven studies in each analysis), resulting in 1 604 sets of patient data being reported more than once. All data in the six meta-analyses come from patients in China. 

What is the risk of smokers being hospitalized for COVID-19?

According to WHO, there are currently no peer-reviewed studies that directly estimate the risk of hospitalization with COVID-19 among smokers. However, 27 observational studies found that smokers constituted 1.4-18.5 percent of hospitalized adults.Two meta-analyses have been published which pooled the prevalence of smokers in hospitalized patients across studies based in China.

Conclusions

At the time of this review, WHO found that the available evidence suggests that smoking is associated with increased severity of disease and death in hospitalized COVID-19 patients.

“Although likely related to severity, no evidence to quantify the risk to smokers of hospitalization with COVID-19 or of infection by SARS-CoV-2 was found in the peer-reviewed literature. Population-based studies are needed to address these questions,” the WHO concluded.

Related WHO Recommendations

Given the well-established harms associated with tobacco use and second-hand smoke exposure;WHO recommends that tobacco users stop using tobacco.

Statistics from the WHO postulate that tobacco causes 8 million deaths every year from cardiovascular diseases, lung disorders, cancers, diabetes, and hypertension.Smoking tobacco is also a known risk factor for severe disease and death from many respiratory infections.

Eswatini has recorded 2 COVID-19 related deaths and information on whether there were smokers could not be established.

Neighbouring South Africa has taken a stance to ban the sale of tobacco during the lockdown because of the belief that available evidence suggest that smokers are susceptible to die from the disease as smoking is associated with increased severity of the disease and death in hospitalized COVID-19 patients.

In papers filed with the high court in Pretoria this week, the South African government for the first time disclosed the scientific studies it says led to the decision to ban cigarette sales during the coronavirus lockdown.

According to Business Day, “in a 17-page affidavit in response to an action by the Fair Trade Independent Tobacco Association, cooperative, Cooperative Governance and Traditional Affairs Minister Nkosazana Dlamini-Zuma speaks at length about the harm cigarettes do generally, and the near-immediate benefits that quitting brings.”

Business Day went on to report that in support of that, Dlamini-Zuma’s affidavit gives the appearance of citing four different studies that found a link between smoking and severe cases of Covid-19, plus another piece of research that proposes a mechanism by which smokers could be making themselves more likely to be infected.

According to Business Day, this is what Dlamini-Zuma told a court about the science behind government’s cigarette ban – and what that research actually says.

On 28 February, well before South Africa’s lockdown, the New England Journal of Medicine published “Clinical characteristics of coronavirus disease 2019 in China” 

Dlamini-Zuma described it to the court like this:

“A large study of 1099 patients with Covid-19 found that, among the patients with severe symptoms, 16.9percent were current smokers and 5.2 percent were former smokers, in contrast to patients with non-severe symptoms where 11.8 percent were current smokers and 1.3 percent were former smokers. In the group of patients that either needed mechanical ventilation, admission to an ICU or die, 25.5 percent were current smokers and 7.6 percent were former smokers.”

Business Day said the second study Dlamini-Zuma cited,  Clinical course and risk factors for morality of adult in patients with COVID-19 in Wuhan, China: a retrospective cohort study” was published by The Lancet on March 11.

She told the court that:

“Another study found that, among those who were infected with Covid-19 and died, 9 percent were current smokers.” The study included data on 191 people, of which 11 were smokers. Five of those smokers died, while six survived.

On Friday, Business day also reported that the British American Tobacco (BAT) SA, the local division of the world’s second-largest cigarette producer, is heading to court to try to overturn the continued prohibition of the sale of tobacco products during SA’s Covid-19 lockdown. 

It has been illegal to sell cigarettes during the course of the lockdown which was imposed during the national state of disaster, in an effort to curb the spread of the novel coronavirus.