Swapping cigarettes for vapes does NOT significantly reduce the risk of lung cancer, study finds
Despite being positioned as a tool for quitting smoking, swapping cigarettes for vapes may not significantly reduce the risk of lung cancer, new research suggests.
Health chiefs have long suggested e-cigarettes are less harmful than traditional smoking products, but Korean researchers now say people who switch to vaping instead of quitting altogether are twice as likely to die from the disease.
The study, involving more than 4.5 million ex-smokers, compared lung cancer risk in those who kicked the habit completely and those who used took up vaping.
Results showed those who vaped had a significantly higher risk of developing lung cancer and were more likely to die from the disease than those who stopped smoking without using e-cigarettes.
The team concluded that while quitting smoking reduces the risk of lung cancer, vaping as a means to do so may reduce the benefits – particularly in over 50s.
Writing in the journal Nature Medicine, Dr Yeon Wook Kim, study lead author and expert in lung cancer risk reduction, said: ‘E-cigarettes are commonly considered a safer option than conventional cigarettes or a smoking cessation aid.
‘However, increasing evidence reveals that e-cigarettes are associated with adverse outcomes in lung-health, including chronic obstructive pulmonary disease (COPD) asthma, and lung cancer.’
The researchers are now calling on officials to reassess the potential harms of vaping when implementing stop-smoking campaigns.
Evidence now suggests that vaping is not nearly as safe as once thought – with vaping as a means to stop smoking increasing the risk of lung cancer
Given the long lag time between carcinogenic exposure and cancer development, the link between vaping and lung cancer risk in the general population has been difficult to quantify.
To get around this, the researchers decided to analyse the effect of vaping on those at high risk of lung cancer.
Only participants with significant cigarette exposure at the start of the study – who were up to 30 times more likely to develop the disease than never-smokers – were included.
Using data from the South Korean National Health Insurance Service database, the team compared lung cancer risk in those who used e-cigarettes to help them quit and those who quit entirely.
Participants were grouped based on how long they had smoked for in pack years – calculated as packs smoked per day multiplied by years smoking – how long they had quit for, and vape-use.
Those who took up vaping after smoking tended to be younger, had fewer pack years, and fewer health problems.
During the study, 35,887 participants were diagnosed with lung cancer, 110,346 died of any cause and 12,807 died from lung cancer specifically.
Compared with ex-smokers who gave up smoking entirely, those who swapped to vaping were significantly more likely to develop, and die from, the disease.
They also had a significantly higher risk of all-cause mortality compared with ex-smokers who were able to kick the habit entirely.
The link was most apparent for high-risk individuals aged 50-80 who had 20 or more pack years.
The researchers suggested this is due to airway inflammation – which has been linked to the development of respiratory diseases – and changes to a user’ DNA, increasing the risk of cell malfunction linked to cancer.
However, compared with current smokers, vape-users were in significantly better health, suggesting the broader health benefits of quitting traditional cigarettes are not completely eradicated by vaping.
The longer people quit for, the lower their risk – regardless of e-cigarette use.
But among ex-smokers over the age of 50, the risk of all-cause mortality did not differ significantly between those who stated vaping and those who had quit completely.
The risks are highest for those who smoke both traditional cigarettes and use vapes, which equates to roughly half of the smoking population; the toxic combination has been estimated to increase their risk of lung cancer four-fold.
The team said their findings prove that incorporating smoking cessation interventions into lung cancer screening programmes is ‘essential’.
‘In this context, our results suggest that complete smoking cessation without e-cigarette use should remain an important goal of integrated counselling programmes,’ they concluded.
The need for more ways to help patients quit smoking is clear, with lung cancer still claiming more than 33,000 lives a year in the UK alone. The COPD burden is also considerably high.
Whilst cigarettes contain dozens of toxic chemicals, including nicotine, the most dangerous of them is tar which damages the lungs and leads to cancerous changes in the cells.
Vapes, in contrast, don’t contain tar or carbon monoxide which experts previously thought were behind cigarettes’ sinister health impacts.
However, they do contain low levels of toxic chemicals such as formaldehyde which drive inflammation, oxidative stress and DNA changes that have been linked to cancer.
It is for this reason the Government has vowed to use its tobacco and vapes bill to crack down on ‘irresponsible’ vaping – including marketing to children and adults vaping in cares if children are present – as well as progressively outlawing smoking.
