Vaping and the data on e-cigarettes

Oxford Dictionaries has selected vape as Word of the Year 2014, so we asked several experts to comment on the growth of electronic cigarettes and the vaping phenomenon.

Vaping is the term for using an electronic cigarette (e cigarette). Since e-cigarette use involves inhaling vapour rather than smoke, it is distinct from smoking. The vapour looks somewhat like cigarette smoke but dissipates much more quickly and has very little odour since it mostly consists of water droplets.

E-cigarettes started to become popular around 2010 and it is estimated they are currently being used by more than 2 million people in the United Kingdom and more than 5 million in the United States. Their sale is banned in many countries, including Australia and Canada, although surveys show that use in these is widespread since they can easily be obtained via the Internet.

E-cigarettes are devices in which a battery-powered heating element vaporises an ‘e-liquid’ usually containing propylene glycol or glycerol, nicotine, and flavourings. They are designed to provide much of the experience of smoking but with much lower risk, less annoyance to bystanders, and usually much more cheaply. Because they do not involve burning of tobacco, the concentrations of toxins in the vapour are typically a tiny fraction of those in cigarette smoke. The precise risk from using them is not known, but based on the vapour constituents it would be expected to be between 1% and 5% that of smoking.

Data on e-cigarette use are not available for most countries. By far the most complete data come from England where the ‘Smoking Toolkit Study’ (STS) collects data on usage from nationally representative samples of adults every month enabling this to be tracked closely over time. This study was established to track ‘key performance indicators’ relating to smoking and smoking cessation and has been going since 2007. Action on Smoking and Health also conducts large national surveys of adults and young people each year. Large scale surveys are also being conducted in the United States and some other countries. The data show that most people use e-cigarettes in an effort to protect their health either by stopping smoking altogether or cutting down. Despite misleading claims by some anti- e-cigarette advocates, use by never-smokers and long-term ex-smokers is extremely rare in the UK and US at present, and in England its prevalence in never-smokers and long-term ex-smokers is similar to the use of ‘licensed nicotine products’ (LNPs) such as nicotine patches, gum, or lozenges.

E-cigarettes come in many different forms. In England, the most commonly used ones at present are known as ‘cigalikes’ because they look something like a cigarette and often have a tip that glows when the user takes a puff. Becoming more popular are devices that involve a refillable ‘tank’. There are also more sophisticated ‘mod’ systems which are highly customised. These are often the choice of aficionados.

Most e-cigarette users probably obtain less nicotine from these devices than people typically do from cigarettes, but experienced vapers using tank systems or mods can obtain at least as much nicotine from their devices as do smokers.

When used in a quit attempt, on average e-cigarettes seem to improve the chances of successful quitting by about 50%, similar to licensed nicotine products when used as directed. The main difference appears to be that these devices are much more popular, and they seem to be effective when people use them without any support from a health professional. Currently the evidence still indicates that use of the drug varenicline or a licensed nicotine product with specialist behavioural support provides the best chance of quitting for those smokers who are willing to use this support and where such support is available.

When used for cutting down, daily (but not non-daily) use of e-cigarettes seems to be associated with a modest reduction in cigarette consumption on average. Use of licensed nicotine products for cutting down has been found to be associated with an increased likelihood of later smoking cessation. This has not yet been demonstrated for e-cigarettes, although smokers who use e-cigarettes daily do try to quit smoking more often than those who are not ‘dual users’.

Despite claims from some anti- e-cigarette advocates, in England and the United States, e-cigarettes are currently not acting as a ‘gateway’ to smoking in adolescents or ‘renormalising’ smoking. Youth and adult smoking have continued to decline steadily as e-cigarette use has grown and in England adult smoking cessation rates are somewhat higher than they were before e-cigarettes started to become popular. E-cigarette use in indoor public areas has not led to any increase in smoking in these areas in the UK and compliance with smoke-free legislation remains extremely high.

Some e-cigarette advertising seeks to glamorise vaping and in some countries appears to blur the boundaries between smoking and vaping. This has led to concern that it might make vaping attractive to non-smokers and countries such as the UK have regulated to prevent this.

There is some controversy over vaping. A number of high-profile public health advocates have engaged in what appears to be a propaganda campaign against them, creating an impression in the public consciousness that they are more dangerous than they are and that they are undermining tobacco control efforts when the evidence does not support this. It is reasonable to be concerned about what may happen in the future with tobacco companies dominating the e-cigarette market and being incentivised to maximise tobacco sales, but much of the anti- e-cigarette propaganda appears to be motivated more by a puritanical ethic than a dispassionate assessment of the evidence. Maximising the public health opportunity presented by e-cigarettes, while minimising the potential threat, requires collecting good data, using this information to construct an appropriate regulatory strategy, and monitoring the situation closely to adjust the strategy as required. England appears to be leading the way in this with an approach designed to encourage smokers to use e-cigarettes to stop smoking, while not undermining use of potentially more effective quitting methods, and preventing e-cigarettes becoming a gateway into smoking. The Smoking Toolkit Study, the ASH surveys, and other research will continue to provide essential information needed to inform this strategy.