Covid-19: DOUBLE smoking the risk of hospitalization, says study

Smoking doubles the risk of developing a severe case of coronavirus and needing hospitalization, says a new study.

The research provides the first conclusive evidence, based on real-world data, that being a smoker puts individuals at greater risk of serious illness than non-smokers.

He found that smokers are 14% more likely to have the three main symptoms of coronavirus: fever, persistent cough and shortness of breath.

But smokers also have a 50% greater risk of developing more than ten symptoms at once – including cough, fever, loss of smell, loss of appetite, diarrhea, fatigue, confusion or muscle pain – than people who do not smoke.

The development of a myriad of symptoms is often an indicator of more serious infection, experts believe.

The data was collected from millions of Britons using the King’s College London ZOE app.

The findings, published in the journal BMJ Thorax, go against previous studies, many of which found that smokers are less likely to get the coronavirus or become seriously ill.

Academics were perplexed by the data, as decades of research have found that smoking tobacco increases the risk of deadly diseases such as lung cancer, strokes and diabetes.

But as the pandemic progressed, new research has emerged, showing that smokers who catch Covid-19 are more likely to see their disease progress quickly and lead to death.

Dr. Mario Falchi, principal investigator and senior speaker at King’s College London, said: ‘Some reports have suggested a protective effect of smoking on the risk of COVID-19.

‘However, studies in this area can be easily affected by bias in sampling, participation and response. Our results clearly show that smokers are at greater risk of suffering from a wider range of symptoms of COVID-19 than non-smokers. ‘

The most recent KCL study provides real information about patients living with Covid and looked at both reported and laboratory confirmed cases.

Application data shows that, of the 2.4 million participants who downloaded the ZOE between March 24 and April 23 last year, 220,135 were smokers – about 11%.

This is slightly less than the UK average of 14% of the population who smoke, but it was representative, say the researchers.

Participants sent a variety of data about themselves, any symptoms that arose as well and any positive laboratory results.

Self-reported data is less reliable, but at this early stage of the pandemic, testing capacity was a fraction of what it is now and was only available in hospitals.

Claire Steves, principal researcher, medical consultant and reader at King’s College London, said: ‘As COVID-19 rates continue to rise and the NHS approaches capacity, it is important to do everything we can to reduce its effects and find ways to reduce hospital admissions.

“Our analysis shows that smoking increases a person’s likelihood of going to hospitals, so quitting is one of the things we can do to reduce the health consequences of the disease.”

At the beginning of the pandemic, when little was known about SARS-CoV-2, the virus that causes Covid-19, researchers instinctively warned that smokers would be at greater risk due to the fact that the coronavirus reaches the respiratory system and the known link between smoking and lung cancer, strokes, diabetes and other chronic conditions that affect that same system.

Artist David Hockney first suggested the idea that smokers may be less at risk because the habit fueled by nicotine hardens the smokers’ immune system and body, leading to more resistant respiratory systems.

The 82-year-old noted in April 2020 that Greece had one of the lowest pandemic mortality rates in Europe, despite having an above average number of smokers. To date, Greece has suffered less than 5,000 deaths and about 133,000 cases.

The UK, in contrast, recorded more than 76,000 deaths and the Office for National Statistics revealed yesterday that there are currently 1.1 million Britons infected with Covid-19 – about one in 50.

Later studies emerged that agreed with Hockney, finding smokers can actually be at reduced risk, and experts fumbled to explain how it could be, calling it ‘strange’ and ‘bizarre’.

Despite the mixed evidence, the World Health Organization declared in June that smoking can make people more susceptible to COVID-19.

But a study published earlier that month in Mexico looked at data from nearly 90,000 patients and found that smokers were 23% less likely than non-smokers to be diagnosed with Covid-19.

And the team also found that infected smokers no longer needed intensive care, needed a respirator, or died.

University College London scholars analyzed 28 articles and found that the proportion of smokers among hospital patients was “less than expected”.

But other studies have been published suggesting that smokers may be at greater risk, however, scientists have, so far, struggled to provide real-world data to support this.

A recent study by academics at UCLA used stem cells grown in the laboratory and found that smoking causes three times as many cells to be infected with coronavirus.

The study showed that smoking prevents essential immune system molecules, called interferons, from functioning properly.

Interferons are messengers that tell infected cells to make proteins to attack the invading pathogen and are essential to fight initial infection.

They also enlist the support of the broader immune system and alert uninfected cells to prepare for the virus.

The study found that smoking prevents this pathway from functioning properly, and this causes a three-fold increase in the number of human cells infected by the virus.

“If you think of the airways as high walls that protect a castle, smoking is like creating holes in these walls,” said Dr Brigitte Gomperts of UCLA in November.

“Smoking reduces natural defenses and this allows the virus to install itself.”