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Nick Hopkinson: Making sense of e-cigarettes—Public Health England’s review of the evidence

I switched over to vaping but someone told me they were just as bad as cigarettes so I went back to smoking again.”

A depressing thing to hear in a COPD clinic, but unfortunately not that uncommon. Worryingly, the proportion of the population with the erroneous belief that vaping is as hazardous as, or more hazardous than, smoking has risen from 7% in 2013 to more than 25% last year. There is a need for clear thinking and guidance in this area. The recently updated report from Public Health England, “E-cigarettes and heated tobacco products: evidence review, is an important contribution to this. Taking a balanced view of the evidence to date, both from clinical research and from surveys of behaviours and attitudes, it addresses common concerns and sets out what we know now and what we can confidently tell patients.

One of the key messages of the report is that vaping is much safer than smoking. Smokers who switch completely to vaping will dramatically reduce their risk of health harms. The relative risk is no more than 5%, a conclusion based on knowledge of the harmful components of tobacco smoke and either their absence, or their presence in much lower quantities, in vapour inhaled from e-cigarettes. Thus according to the report, “the constituents of cigarette smoke that harm health—including carcinogens—are either absent in e-cigarette vapour or, if present, they are mostly at levels much below 5% of smoking doses (mostly below 1% and far below safety limits for occupational exposure). In addition, the main chemicals present in e-cigarettes only have not been associated with any serious risk.

According to the report, most people who start to use e-cigarettes are doing so in order to cut down or quit smoking. There is no evidence that the use of these novel electronic nicotine delivery systems is undermining attempts to quit smoking. In fact, the best estimate of their impact on smoking suggests that they are responsible for tens of thousands more successful quit attempts annually.

Data from Stop Smoking services, presented in the report, show that in the context of this kind of support, quit attempts using e-cigarettes are as effective as with pharmacotherapy. Stop Smoking services should support smokers who wish to quit using e-cigarettes. The ongoing cuts to these services are a more important focus for concern.

Vaping is not harmless and uptake by non-smokers should be discouraged. However, data so far suggest that use is confined almost entirely to current or ex-smokers. For ex-smokers, quitting e-cigarette use in the long term is also desirable, but not at the expense of relapse to smoking.

Efforts to prevent uptake of vaping by children are in place, including a ban on purchase by under 18s. The government’s political choice to pursue austerity policies has been associated with a 56% reduction in Trading Standards office staff since 2009, which will have an impact on enforcement.

The report’s authors note that “widespread misconceptions about the relative risks of nicotine and tobacco need to be addressed and corrected.” E-cigarettes are new and unfamiliar. Many healthcare professionals are naturally suspicious about how e-cigarettes will be used, but evidence to date suggests that these fears are unfounded. The PHE report provides a clear road map, with the evidence needed to advise smokers and policy makers.

The National Centre for Smoking Cessation and Training (NCSCT) has produced a useful online course E-cigarettes: a guide for healthcare professionals

Nicholas Hopkinson, reader in Respiratory Medicine, Imperial College London.

Competing interests: None declared.