Vaping increases the chances of regular smoking threefold, Australian review finds

29 September 2020

Melissa Davey, The Guardian:

Every one of 25 existing studies examined found people who use e-cigarettes are more likely to take up ‘combustible’ smoking

Using e-cigarettes triples the chance of a non-smoker taking up regular cigarettes, a review of the public health impacts of vaping has found.

Researchers led by the Australian National University’s national centre for epidemiology and population health examined 25 research studies on e-cigarette use and smoking uptake from around the world as part of their review for the federal government. They found e-cigarettes are a gateway to smoking, especially among young people.

“This review found consistent evidence that use of e-cigarettes, largely nicotine-delivering, is associated with increased risk of subsequent combustible smoking initiation, current combustible smoking and smoking relapse after accounting for known demographic, psychosocial and behavioural risk factors,” the review concluded.

It is the first review to examine associations between e-cigarette use and cigarette use across the whole population, including youth, adults and former smokers.

The lead researcher of the e-cigarette and smoking uptake paper, Prof Emily Banks, said every one of the 25 existing studies examined by her team found those who used e-cigarettes were more likely to take up smoking than those who had not used tobacco or e-cigarettes.

She said the magnitude of that risk varied depending on the country the research was done in, but on average non-smokers were three times more likely to take up tobacco smoking if they used e-cigarettes.

“In some places smoking is common and in Australia, it is much more uncommon, and we are now at the point where 97% of teenagers have never smoked,” Banks said.

“We don’t want to jeopardise that incredibly strong position Australia is in by introducing something that might increase the probability that they might smoke, and pick up a very deadly habit.”

The work is preliminary and forms part of a broader e-cigarette review funded by the federal government, which is looking at overall smoking trends in Australia and is due to deliver its final report in June. The next stage of the work is to review health outcomes in relation to e-cigarette use and to conduct a public health assessment of e-cigarettes specifically for Australia.

Despite world-leading tobacco control and declines in smoking rates, smoking remains Australia’s leading cause of preventable disease and death, including for Aboriginal and Torres Strait Islander peoples. There are around 2.3 million smokers in Australia.

Banks said there was limited evidence that e-cigarettes helped people give up smoking. Ex-smokers using e-cigarettes are more than twice as likely to relapse.

“Most people who give up smoking successfully don’t use any products like patches or medication to do it – they do it by themselves, for example by going cold turkey,” Banks said.

“Our review found that there wasn’t sufficient evidence to conclude that e-cigarettes are effective for quitting smoking compared to other approaches, but there are promising signs that they have potential to help. The evidence also indicates that e-cigarettes tend to lead to prolonged use of nicotine, rather than quitting the habit entirely.”

Current guidelines from the Royal Australian College of General Practitioners has e-cigarettes listed as a last resort for quitting after other measures.

A senior lecturer with the University of Sydney’s school of public health and a leading tobacco control researcher, Dr Becky Freeman, said while it was difficult to synthesise the results from multiple e-cigarette studies because the policy environments of the countries they were conducted in varied so greatly, the notion that non-smokers are more likely to go on to smoke if they first vape is consistent with other reviews.

“But the magnitude of this effect, as acknowledged by the authors, is highly variable,” Freeman said. “The Centers for Disease Control and Prevention in the US, for example, cites the same 2018 National Academy of Medicine report referenced by the authors as evidence that users may be more likely to go on to smoke.”

However, she described any debate as to whether or not e-cigarette users go on to smoke as “a bit of a red herring”.

“E-cigarette use by young people is unsafe, even if they do not progress to cigarette smoking,” Freeman said. “The argument by some that vaping protects youth from future smoking has not been proven.”