Junk e-cigarette study debunked

Stanton Glantz is up to his old tricks

A study published in the Journal of Adolescent Health last year ended with a striking recommendation.

Physicians, regulators, and educators should discourage youth from attempting to use e-cigarettes as a way to stop smoking cigarettes.

Did a cigarette company write that?

No, it was California’s junk science veteran Stanton Glantz who had trawled through the US National Youth Tobacco Survey looking for something that would support his weird theory that vaping makes people smoke.

Ever-smoking youth who used e-cigarettes “to try to quit using other tobacco products, such as cigarettes” had lower odds of having stopped smoking cigarettes than those who did not use e-cigarettes as to try to quit.

On the face of it, this seems unlikely. Vaping has helped millions of adults around the world quit smoking, so why wouldn’t it work for American teenagers?

Like many counter-intuitive findings, this one turns out to be untrue. In a thorough critique, Floe Foxon and Saul Shiffman show that Glantz classified people as smokers if they had ever smoked. Quite obviously, somebody is not going to use e-cigarettes to quit smoking if they haven’t had a cigarette in years and never smoked them much to begin with.

Glantz’s analysis included all adolescents who report having ever smoked, regardless of the extent of their smoking history (i.e., including adolescents who had not even smoked a single whole cigarette). However, many adolescents have only smoked a few puffs or one or two cigarettes. It seems likely that these adolescents who had barely smoked would be both unlikely to be smoking at the time of the survey, and unlikely to report using e-cigarettes to quit smoking, as it seems unlikely that they would consider themselves as needing an aid to stop smoking, and indeed, might not think of themselves as a person who smokes at all.

Of the ‘smokers’ in Glantz’s sample, only 18.7% had smoked 100 cigarettes or more in their lives (which is the usual definition of a smoker in epidemiology). The majority (54.3%) had never smoked more than five cigarettes and 29.4% had never even smoked a whole cigarette. Unsurprisingly, it was “extraordinarily rare” for someone who had only had a few puffs of a cigarette to use an e-cigarette to quit smoking whereas 37% of the people who had smoked more than 100 cigarettes in their life had used an e-cigarette for this purpose.

When Foxon and Shiffman confined their analysis to people who could be reasonably described as smokers, they found the opposite of what Glantz claimed.

… when the analysis is focused on adolescents with established smoking (100+ cigarettes), those who reported using e-cigarettes to stop using tobacco had significantly greater odds of reporting no smoking for the 30-days before the survey. In other words, for adolescents who already have established smoking, using e-cigarettes to help stop smoking is associated with abstinence from smoking.

Whadya know?!

Foxon and Shiffman are barely able to hide their contempt for Glantz’s contemptible quackery in their conclusion…

Not surprisingly, adolescents who have done very little smoking in the past are more likely to report that they have not smoked recently. Also not surprisingly, they are less likely to report that they used e-cigarettes to help them stop smoking, as many had barely started smoking. These associations bias and confound the relationship between recent abstinence and use of e-cigarettes to stop smoking. When these associations are fully taken into account, removing this confounding, the finding reported by Glantz disappears. Glantz interpreted the association as causal, making policy recommendations based on this. In fact, the cross-sectional observational associations were due to confounding, and do not support the policy recommendations Glantz proposed.

A similarly awful study by Glantz was retracted in 2020, but it doesn’t look like that will happen this time because the journal decided not to publish Foxon and Shiffman’s critique, presumably because they are consultants for the e-cigarette company Juul. True to form, Glantz has refused to discuss the substantive criticisms of his study and has instead responded by wittering on about Juul.

UPDATE: 8 November

Glantz’s response, such as it was, has been removed by the moderator.