Nicotine e-cigarettes are more effective in helping people quit smoking than conventional nicotine-replacement therapy (NRT), according to the latest Cochrane review co-led by a University of Massachusetts Amherst public health and health policy researcher.
The review of studies published on the Cochrane Database of Systematic Reviews found high certainty evidence that e-cigarettes, which allow users to “vape” nicotine instead of smoke it, lead to better chances of quitting smoking than patches, gums, lozenges, or other traditional NRT.
“In England, quite different from the rest of the world, e-cigarettes have been embraced by public health agencies as a tool to help people reduce the harm from smoking,” says Jamie Hartmann-Boyce, assistant professor of health policy and promotion in the School of Public Health and Health Sciences.
Worldwide, smoking is the leading cause of preventable disease and death, resulting in more than seven million deaths per year. “Most of the adults in the US who smoke want to quit but many find it really difficult to do so,” said Hartmann-Boyce, who conducted research at the University of Oxford in England before joining UMass Amherst earlier this year. “We need a range of evidence-based options for people to use to quit smoking, as some people will try many different ways of quitting before finding one that works for them.”
Hartmann-Boyce, a Cochrane editor, is senior author of the review, which included 88 studies and more than 27,235 participants – an addition of 10 studies since the last update in 2022. Most of the studies analysed took place in the US, the United Kingdom, or Italy.
E-cigarettes do not burn tobacco but rather heat liquids with nicotine and flavourings, allowing users to inhale a vapor that contains nicotine rather than inhale tobacco smoke. With conventional cigarettes, people who smoke are exposed to a complex mix of chemicals that are known to cause diseases.
“We have very clear evidence that, though not risk-free, nicotine e-cigarettes are substantially less harmful than smoking,” Hartmann-Boyce said. “Some people who haven’t had success in the past with other quit aids have found e-cigarettes have helped them.”
The analysis found that for every 100 people using nicotine e-cigarettes to stop smoking, eight to 10 would be expected to successfully stop, compared with six of 100 people using traditional nicotine-replacement therapy, and with four of 100 trying to quit with no support or behavioural support only.
The regular review of smoking cessation studies continues to offer strong evidence that can inform public health policies and strategies, offering people who smoke better tools to quit for good. Hartmann-Boyce emphasises that the public health message is a nuanced and complex one, especially in the US.
While those who don’t smoke tobacco should avoid the use of e-cigarettes for their potential negative health effects, Hartmann-Boyce says, some people who smoke can improve their health and reduce their risks by quitting tobacco with the help of e-cigarettes.
“Not everything is either entirely harmful or beneficial,” Hartmann-Boyce says. “Different things can have different impacts on different populations. Evidence shows that nicotine e-cigarettes can help people quit smoking, and that people who don’t smoke shouldn’t use e-cigarettes.”
She compares the tobacco smoking versus e-cigarette scenario to treatment for a substance-use disorder involving opioids. “We’re not going to prescribe methadone to people who aren’t addicted to opioids,” Hartmann-Boyce added. “But for people addicted to opioids, we recognise that methadone is a helpful thing.”