E-cigarettes are certainly not 95 percent safer than smoked tobacco, as has been claimed, and its value in helping people quit has been exaggerated, health experts warn.
Several deaths in the United States attributed to vaping have prompted President Trump to announce that all flavoured vaping liquids will be banned.
In New Zealand, the plan is to restrict the flavours to three – tobacco, menthol and mint – in order to reduce the appeal of vaping to young people.
It's been reported that the deaths and illnesses have been due to specific vaping liquids – containing THC or cannabinoids, and vitamin E acetate – but still debate is raging about whether vaping is as safe as we have been told.
Some of its advocates, including Associate Minister of Health Jenny Salesa, say that it is 90 percent to 95 percent safer than smoking.
However, top European public health expert Martin McKee – an outspoken critic of vaping, who was made a CBE for his contribution to public health – has recently completed a review of 38 studies, and found electronic cigarettes have a potentially negative effect on heart health.
He tells RNZ Saturday Morning’s Kim Hill that too little is known about the effects of vaping, and its value in helping people quit smoking has been exaggerated.
“What we found was that there were a whole series of mechanisms by which e-cigarettes were making changes in the arteries, in particular that could be associated with a higher risk of having cardiovascular disease – heart disease – and stroke.
University of Otago public health department Professor Richard Edwards says Prof McKee’s review was very comprehensive, although it is by necessity restricted by the studies available.
“So for example it is only looking at the sort of short term metabolic effects ... it's not looking at the long term effects and it's not – importantly – it's not looking at the effects on actual occurrence of clinical heart disease, heart attacks, and so on. It's just saying, look, there's some evidence here that vaping can increase the heart rate, can affect the endothelial function.
“That might make us concerned that this could translate into effects – and real effects, clinical effects of heart disease – but it doesn't show that.”
‘Utterly implausible’ that vaping 95 percent less harmful
Prof McKee says while Public Health England had at one point supported vaping as being “95 percent safer” than cigarettes, they are alone in that.
“There are very few other organisations that take that view. The World Health Organisation has extreme concern ... I think yesterday the chief medical officer and the State Health Officers in Australia have come up with a fairly strong statement; the former Chief Medical Officer of Scotland wrote yesterday in The Scotsman that he was not persuaded that e-cigarettes were necessarily much safer. The European Respiratory Society, European Heart Network, many of the American organisations, I could go on.”
He says Public Health England has also wavered in its support, particularly for the 95 percent figure anyway.
“The 95 percent figure has no credibility whatsoever … they used a method for collective decision making which is a perfectly valid method if you have a wide range of opinions and different views - but in fact, the people around the table almost all were strong supporters of electronic cigarettes at a time when there was very little evidence.
“They conceded in their paper that in fact there was not enough evidence to come to firm conclusions - but they did anyway – and there are very significant and still unanswered questions about the funding for that study that have been described in the British Medical Journal and elsewhere.”
Prof Edwards agrees, saying such a specific figure was “utterly implausible”.
“What we can say is that vaping is going to be safer than – less harmful than – smoking, and probably substantially less harmful than smoking.
“I think it was ... they wanted to show that it was a lot safer, and they wanted to put a number on it. I think some people on that committee might have regretted that, because it's become this, sort of, factoid.
"Smoking causes 50 odd diseases, each with a relative risk of if how much your risk increases, we don't know the long term effects of vaping. So to put up the 90 to 95 percent figure is clearly ridiculous.”
Prof McKee says there is also a worry about the influence of tobacco and vaping industries, with his research showing a startling difference between studies funded by tobacco or vaping industry and those that are independent.
“Those studies that were independently funded ... they were consistently finding a harmful effect. However, when we looked at the studies that were funded by the industry, they were in general not finding a harmful effect.
“The studies that were not independent tended to look for measures of physiological measures that you would not necessarily expect to be affected, and then you can say that ‘there's no harmful effect observed’.
“Of the studies that find no ... harmful effect with the electronic cigarettes, all were funded by industry bodies or, in two cases, they didn't have a very high level of exposure – in fact, too low a level of exposure to have any effect.”
Other health effects
Prof McKee admits the risk of lung cancer from vaping are still lower than for smoking cigarettes, but points to the effects those independent studies found.
“In conventional cigarettes you get tar which clearly causes lung cancer and you do not get those in the electronic cigarettes,” he says.
However, the health effects from vaping – alongside the suspected effects on arteries and the heart – could still be serious, he says.
"In the electronic cigarettes there are concerns about the aerosol that is produced the liquid aerosol and also, in particular, the flavourings.”
He says the flavourings are often made with food additives, but the difference between ingesting something through the gut versus something through the lungs is completely different.
“They've been tested as food additives, but there are lots of things that we eat that are potentially dangerous.
"Over millennia, humans have evolved in a way that allows blood from the gut to be taken straight to the liver before it's released into the rest of the circulation, and lots of toxins are removed. We don't have that anatomical mechanism with the lungs, they go straight into the circulation.”
Electronic cigarettes also use propylene glycol, which he says may also be a risk, as a means of transporting the flavouring and nicotine to the lungs.
“The concern there is not just so much the propylene glycol in itself, but that you are heating it and there are concerns that ... there is a danger of producing formaldehyde, which is a known cancer-producing agent.
“Also the micro particles ... this is something where much of the work has been done with air pollution, very small particles, and it does seem to have a disruptive effect on physiology as well.”
Even nicotine itself is not fully safe, he says.
“We do know that people who have had heart attacks, for example, who are using nicotine replacement therapy are more likely to have abnormal rhythms and to die as a result of that. And also there is evidence that it does affect the developing brain in younger people; and also some evidence that in people who have cancer, that it can increase the growth of blood vessels and the spread of the cancer.
“Now, these are not big effects. They're not hugely problematic, but they do exist and we can’t ignore them completely.”
Vaping as a treatment and the dangers of dual-use
Prof McKee argues the effectiveness of using vaping to quit cigarettes is questionable, saying the majority of people who quit do so unaided, and a new study from New Zealand has found 93 percent who used electronic cigarettes had not quit.
“If you had an antibiotic and it only cured 7 percent of people I think you would be very concerned as to whether it was really particularly effective ... and if you are wanting to use therapeutic interventions then there are other medicines which do seem to work as well, which don't have the problems.”
Prof McKee also says that while vaping may be of some limited use in quitting smoking, there’s plenty of evidence that it also leads to dual use, which is particularly concerning if people begin by vaping without having smoked cigarettes previously.
“While you do find people who quit both quit vaping and quit smoking, you find about twice as many people who go the other direction - either moved from electronic cigarettes alone to smoking and vaping or go from both to exclusive smoking,” Prof McKee says.
“There is evidence of young people moving on to cigarettes again in the United States, so I don't think that's a question. That's clearly the case.
“There's also some evidence that people who use electronic cigarettes to quit have a higher relapse rate as well.”
The studies which show electronic cigarettes are effective also all pair it with intensive behavioural interventions and counselling, a point which Prof Edwards says further complicates things.
“If you look at randomised controlled trials like the big New Zealand randomised controlled trial that was released last week, it showed that vaping together with a nicotine patch had a more effect on quitting than a nicotine patch alone.
“But in the real world situation without that support, it's really much less clear. They probably help a bit, but some studies actually show the opposite.
“What happens to people out in the community who aren't necessarily getting that behavioural support? What happens when they vape? Are they more likely to quit or are they going to dual-use and carry on dual-using and therefore they might even be less likely to quit.”
Prof Edwards also says it’s that prospect of dual use - vaping as well as smoking cigarettes - which is the most concerning health-wise, because merely reducing smoking tobacco does not help reduce the risks.
“Say you cut down from 20 to 10 [a week] – that does not reduce your risk very much of smoking-related diseases. You really need to stop completely.
“So dual use - so if people vape and say ‘oh, I've cut down on smoking so that's good enough, I'm vaping,’ it’s not good enough in terms of your health. You're still at high risk.”
Despite his strong opposition to vaping, Prof McKee agrees with Kim Hill that the cat is out of the bag, and says prohibition is not the answer.
“There definitely is a challenge there, I've no illusions about that … and these products may have some role for some individuals within a structured behavioural programme.”
However, when it comes to regulation, he sees no need for vaping products to be advertised, or have any flavourings whatsoever.
“Other people have used the word ‘reckless’ to describe the promotion of these products until we have a much better understanding of their safety profile and what it is that seems to be causing these problems with some people.
“I think if we treat them as a medicine – albeit a very ineffective medicine, as I've said, with a very low success rate – then perhaps that might be the best way forward, and then see how things pan out.”
Prof Edwards says the government is now looking at introducing its bill to regulate vaping to some extent within the next month or so.
“We don't know what they're going to look like yet, I mean … where they can be sold, flavours, where you can vape, all these different things need to be covered.
“We're really trying to balance – we want vaping to be available for smokers who want to quit, but we don't want kids and young people starting to vape, both because we don't want them starting to vape but we also worry that starting to vape might result in smoking later.”
He says overall, the risks from vaping do appear to be much lower than from smoking tobacco, and argues that effective regulation could help reduce the likelihood of dual use.
“We shouldn't always be talking about ... ‘vaping’ regulation. It's important but I would say even more important is how we regulate smoked tobacco products.
“If we make regulation on smoked tobacco products more and more strong, then vaping is less likely to result in that drug use or people relapsing from vaping to smoking, or kids going from vaping to smoking.”
He also says the Food and Drug Administration in the US is also considering removing nicotine from smoked tobacco products, to make them less appealing.
“Then if you could get nicotine through vaping products, but your tobacco product was pretty useless because it didn't give you nicotine, why would you relapse back to tobacco once you've quit?”
Quit smoking advice
Prof Edwards says quitting smoked tobacco is the most important objective.
“It's incredibly important to try and give up smoking … try the established products like nicotine patches and nicotine replacement, try e-cigarettes if that's what is appealing to you.
“Think about when you're trying to give up, so don't give up when you're in the middle of a family crisis or something like that … try and find a time which is a good time when you can try and get support from people around you, from family and friends.
"Go to a smoking cessation service, ring the quit line, they give very, very expert advice about this. There's lots of things you can do.
"I would say the main thing is don't get dispirited if you don't succeed. Next time, you're more likely to successfully quit.”