November 18, 2022
The latest Cochrane review has found the strongest evidence yet that e-cigarettes help people to quit smoking better than traditional nicotine replacement therapies, such as patches and chewing gums.
New evidence published on Thursday in the Cochrane Library finds ‘high certainty’ evidence that people are more likely to stop smoking for at least six months using nicotine e-cigarettes, or vapes, than using nicotine replacement therapies, such as patches and gums.
Evidence also suggested that nicotine e-cigarettes led to higher quit rates than e-cigarettes without nicotine, or no stop smoking intervention, but less data contributed to these analyses.
The updated Cochrane review includes 78 studies in over 22,000 participants – an addition of 22 studies since the last update in 2021.
An international network with headquarters in the UK, Cochrane gathers and summarises the best evidence from medical research findings to help make informed choices about health interventions involving health professionals, patients and policy makers.
Data from the review showed that if six in 100 people quit by using nicotine replacement therapy, eight to twelve would quit by using electronic cigarettes containing nicotine. This means an additional two to six people in 100 could potentially quit smoking with nicotine containing electronic cigarettes.
“Electronic cigarettes have generated a lot of misunderstanding in both the public health community and the popular press since their introduction over a decade ago. These misunderstandings discourage some people from using e-cigarettes as a stop smoking tool. Fortunately, more and more evidence is emerging and provides further clarity,” Dr Jamie Hartmann-Boyce, Associate Professor at the University of Oxford, Editor of the Cochrane Tobacco Addiction Group, and an author of the new publication, said.
“With support from Cancer Research UK, we search for new evidence every month as part of a living systematic review. We identify and combine the strongest evidence from the most reliable scientific studies currently available.
“For the first time, this has given us high-certainty evidence that e-cigarettes are even more effective at helping people to quit smoking than traditional nicotine replacement therapies, like patches or gums.”
In studies comparing nicotine e-cigarettes to nicotine replacement treatment, significant side effects were rare, the review added. In the short-to-medium term (up to two years), nicotine e-cigarettes most typically caused throat or mouth irritation, headache, cough, and feeling nauseous. However, these effects appeared to diminish over time.
“E-cigarettes do not burn tobacco; and as such they do not expose users to the same complex mix of chemicals that cause diseases in people smoking conventional cigarettes,” Dr Nicola Lindson, University Research Lecturer at the University of Oxford, Cochrane Tobacco Addiction Group’s Managing Editor, and author of the publication, commented.
“E-cigarettes are not risk free, and shouldn’t be used by people who don’t smoke or aren’t at risk of smoking. However, evidence shows that nicotine e-cigarettes carry only a small fraction of the risk of smoking. In our review, we did not find evidence of substantial harms caused by nicotine containing electronic cigarettes when used to quit smoking. However, due to the small number of studies and lack of data on long-term nicotine-containing electronic cigarette usage – usage over more than two years – questions remain about long-term effects.”
The researchers conclude that more evidence, particularly about the effects of newer e-cigarettes with better nicotine delivery than earlier ones, is needed to assist more people quit smoking. Longer-term data is also needed.