A large study in England has found that smokers trying to quit were substantially more likely to succeed if they used electronic cigarettes than over-the-counter therapies such as nicotine patches or gum. These results offered encouraging but not definitive evidence in the contentious debate about the risks and benefits of these increasingly popular smoking devices.
Researchers interviewed almost 6,000 smokers who had tried to quit on their own without counselling from a health professional. About a fifth of those who said they were using e-cigarettes had stopped smoking at the time of the survey, compared with about a tenth of people who had used patches and gum.
“This will not settle the e-cigarette issue by any means,” said Thomas J Glynn, a researcher at the American Cancer Society, who was not part of the study, “but it is further evidence that, in a real-world context, e-cigarettes can be a useful, although not revolutionary, tool in helping some smokers to stop.”
The use of e-cigarettes has risen rapidly across Europe and the United States, and regulators are scrambling to figure out how to respond in the absence of hard evidence about their effects. The debate is particularly fierce in the United States, where some experts say the devices could lure children to start smoking, while others contend that they are the best hope in generations to get smokers to switch to something less dangerous than traditional cigarettes.
The central question is whether e-cigarettes will cause the ranks of smokers to shrink or swell.
So far, the evidence is too thin to provide a convincing answer. The Food and Drug Administration has commissioned a broad study, but its results will not be known for years. A clinical trial in New Zealand, which many researchers regard as the most reliable study to date, found that people given e-cigarettes had only a slightly better quit rate than those with patches.
While the long-term health effects of e-cigarettes are unknown, many health experts believe that the concentrations of toxins in the vapour are much lower than in cigarette smoke.
The English study was not a clinical trial, the gold standard of scientific research, in which participants would have been randomly assigned to different groups: for example, one that used e-cigarettes to quit and another that used nicotine replacement therapies. But authors of the study said that they controlled for many factors. They also said the study, one of the largest to date, offered valuable insights into the real world experiences of smokers.
Professor Robert West, director of tobacco studies at University College London and senior author of the study said clinical trials could not answer the question most people have about whether e-cigarettes help smokers quit because the devices are changing so fast that they become obsolete before an experiment ends.
The standard recommended practice for helping people quit is a prescribed medicine such as Chantix or a combination of nicotine patch and gum together with counseling from a trained professional.
But even in England, where these options are widely advertised and nearly free, the majority of smokers rely on willpower or nicotine products bought from a store, and success rates are low.
The study found that the rate at which smokers quit by using e-cigarettes was similar to that for people who used prescribed nicotine therapy with brief counselling.