E-cigarettes nudge people towards quitting smoking, major study shows

E-cigarettes do have value as a smoking cessation aid, according to a new study just released by a team of researchers at MUSC Hollings Cancer Center in South Carolina, US.

This new study, the largest trial of e-cigarettes in the US, showed that e-cigarette usage nudged people toward quitting smoking – even people who had entered the trial saying they had no intention of quitting.

“This is not a panacea for smoking cessation,” cautioned Matthew Carpenter, first author on the paper published in eClinical Medicine this month and co-leader of the Cancer Control Research Program at Hollings.

Nonetheless, he was surprised to find that all of the hypotheses tested in the study were confirmed.

“It’s rarely the case that you’re proven correct for almost everything that you predicted,” he said. “Here, it was one effect after another: No matter how we looked at it, those who got the e-cigarette product demonstrated greater abstinence and reduced harm as compared to those who didn’t get it.”

Carpenter and his colleagues designed the study in a naturalistic way to mimic real-world conditions as much as possible.

Previous studies that have shown a smoking cessation benefit of e-cigarettes have been very structured, Carpenter said, in that they recruited people who wanted to stop smoking and gave them very detailed instructions about how to use the e-cigarettes.

“Some people have said, ‘That’s fine, but the results of those studies don’t apply to the real world because the real world isn’t as structured,’” he explained. “So what we did was take a hands-off approach – we called it a naturalistic approach.”

“First off, we took smokers who did and did not want to quit. So right off the bat, not everybody wanted to quit. Secondly, we gave them very little instruction on how to use it,” he continued.

Instead, people were given e-cigarettes and told they could use them or not, as much or as little as they wanted. A control group didn’t receive anything.

The study showed that people in the e-cigarette group were more likely to report complete abstinence from combustible cigarettes. They were also more likely to report that they’d reduced the number of cigarettes per day that they smoked and their number of ‘quit attempts.’ Quit attempts are an important metric because people usually need multiple tries before they can successfully stop smoking.

The study included people from 11 cities across the US and spanned four years. At the beginning, Carpenter intended to collect biochemical samples from participants in the Charleston area in South Carolina to verify their self-reports of smoking behavior. However, Covid interrupted that plan and made in-person sample collection impossible.

Although that was a disappointing aspect of the study, replying on participants’ self-reports of their smoking behavior is still considered highly reliable, he said.

The study will be another data point for the public health community and policymakers in deciding how to handle e-cigarettes.

“No one wants e-cigarettes in the hands of kids, and we should do all we can to stop that. But we shouldn’t do so by denying this option for adult smokers who can’t otherwise quit,” Carpenter said.