Do Vaping Products Actually Help Smokers Quit?

While most agree that quitting cigarette smoking is important, there is disagreement on the best approach to achieve this. After a landmark Surgeon General report came out in 1964 warning of the dangers of smoking, the search for alternatives began. For some, this included working with the tobacco industry to develop a “safer” nicotine product. The first attempt to get a “safer” cigarette led to the debacle that was “light” cigarettes (proven to be no more safe than traditional cigarettes), and today, the harm reduction focus is now on switching to “safer” e-cigarettes, also known as vaping products.

Following a court mandate for a public health review of vaping products, the agency recently granted marketing approval for RJ Reynolds Vapor Company’s Vuse Solo e-cigarette — the only e-cigarette approved so far. The agency concluded that the manufacturer’s data suggested this product may benefit adult cigarette smokers who switch to these e-cigarettes by reducing their exposure to the harmful chemicals in traditional cigarettes.

But aside from the manufacturer’s data, what does the scientific evidence say about e-cigarettes and cessation? Since 2007, e-cigarettes have been marketed in the U.S., where we have excellent surveillance systems to identify trends in smoking. Perhaps the best of these systems is the FDA-funded Population Assessment of Smoking and Health (PATH) Cohort Study (launched in 2013). Below, I answer a few relevant questions based on an evaluation of the data and trends in the PATH studies in order to contextualize FDA’s current review of e-cigarettes.

Has the popularity of e-cigarettes as a cessation aid resulted in an increase in the proportion of cigarette smokers trying to quit?

No. Starting about 6 years ago, smokers became more likely to use e-cigarettes to help them quit than smoking cessation aids such as nicotine replacement therapy (NRT), varenicline (Chantix), or bupropion (Zyban). Yet, there are no reports suggesting that more smokers are trying to quit, and for most states in the U.S., there has been no discernable change in the proportion of smokers who try to quit each year.

What is the evidence that using e-cigarettes to quit smoking results in more people quitting a year later?

Randomized clinical trials are the best methodology to address efficacy questions. However, there is only one trial from the U.K. that has reported that e-cigarettes, when used in a clinic setting with behavioral support, outperformed NRT in promoting cessation 1 year later. Many other trials have been inconclusive. But most smokers who are using e-cigarettes to quit are not using them in a clinic setting where they are carefully monitored and receive behavioral support. They are buying them as a consumer product at a local store.

There are a number of analyses of smokers trying to quit in the PATH Study data over the past few years. As this is a population-based study and not a randomized trial, special care needs to be taken to ensure that the control group has an equivalent level of motivation to quit as the group that used e-cigarettes to quit. No studies that have used an appropriate control have reported any advantage to U.S. smokers using e-cigarettes to help a quit attempt.

If the key issue is switching to another nicotine source, what is the evidence that smokers who switch to e-cigarettes are able to continue using them without relapsing to cigarette smoking?

This is the key question for those who advocate for the “harm reduction” hypothesis. Proponents argue that public health would be better served by moving away from promoting quitting completely and toward a recommendation to switch to a “safer” source of nicotine, like e-cigarettes. While this is a key question for proponents, there is not a single randomized trial to date that has tested whether smokers are able to successfully switch to e-cigarettes without relapsing.

Recently, my co-authors and I published a paper in JAMA Network Open addressing this question. Using the PATH Study, we identified 13,604 cigarette smokers on the first survey, and 9.4% had quit smoking cigarettes by the following survey. At this second survey, two-thirds had quit nicotine altogether — 23% had switched to e-cigarettes (17.6% were daily users) and 14% were using some other form of tobacco. We then followed them for another year to identify who was able to stay off cigarettes. Those who switched to using e-cigarettes (daily or not) were not less likely to relapse to cigarette smoking compared to those who quit nicotine completely. Indeed, successful quitting was similar for all groups who had switched to another form of nicotine (~42%), which was below the 50% successful quitting among those who had quit nicotine altogether.

What about young people starting to use nicotine?

The early data from the PATH Study showed that e-cigarette advertising was very influential in young adolescents and was associated with experimentation with both cigarettes and e-cigarettes. However, 70% of those who progressed to become addicted did so by becoming daily cigarette smokers. In 2017, a new generation of high-nicotine e-cigarettes (e.g., JUUL) started to become popular — and these may change how young people become nicotine dependent. Cross-sectional high school data indicate that frequent nicotine vaping increased markedly starting in 2018. We expect the PATH Study data on JUUL in the next year.

So what should we do?

Over the past 14 years, e-cigarettes have become popular among smokers who are trying to quit as well as teenagers experimenting with nicotine. The PATH Study offers excellent longitudinal evidence with 5 years of data already publicly available and at least 2 more years currently being prepared for release. So far, this population study has found no evidence that e-cigarettes are helping smokers quit successfully, and the evidence on teen initiation is troubling. While all the evidence is not in yet, the data we have to date suggests we should not embrace the harm reduction hypothesis, but stay the course on promoting abstinence from all nicotine. After all, in the past 20 years, there has been a major reduction in cigarette smoking in the U.S., little to none of which is attributable to e-cigarette use.

John Pierce, PhD, is a Distinguished Professor for Cancer Prevention at the Moores Cancer Center and the Herbert Wertheim School of Public Health and Human Longevity Science at UC San Diego.