Tuesday, April 08, 2014

Americans for Nonsmokers' Rights Spreading False Information About Health Effects of Electronic Cigarettes

According to a "fact sheet" on the Americans for Nonsmokers Rights (ANR) web site, short-term use of electronic cigarettes impairs lung function and can cause difficulty breathing:

"Short term use of e-cigarettes has been shown to increase respiratory resistance and impair lung function, which may result in difficulty breathing."

The citation provided to back up this assertion is a study by Vardavas et al. (Vardavas, C.I.; Anagnostopoulos, N.; Kougias, M.; Evangelopoulou, V.; Connolly, G.N.; Behrakis, P.K., "Short-term pulmonary effects of using an electronic cigarette: impact on respiratory flow resistance, impedance, and exhaled nitric oxide," Chest 141(6): 1400-1406, June 2012.).

The Rest of the Story

The rest of the story is this study actually found no effect of electronic cigarette use on pulmonary function tests, indicating that there was no clinically significant observable effect of vaping on lung function. Specifically, the study found "no differences between basic pulmonary measurements" between the two groups, demonstrating that acute exposure to electronic cigarette vapor did not affect FEV1, FVC, PEF or MEF50 and MEF75."

In contrast to what ANR is stating, the study found no effect of e-cigarettes on lung function, as measured by spirometry. This is in contrast to tobacco smoking, which does have effects on lung function that can be measured using spirometric testing. While previous research indicates that active smoking and even secondhand smoke exposure can affect acute lung function as measured by spirometry, the study demonstrated that electronic cigarette use led to no impairment of lung function detectable via spirometric testing.

What the study did show was subclinical evidence of impaired lung function, meaning that the observed (measurable) lung function was unchanged, but that there was evidence of physiologic effects consistent with some bronchial inflammation. What is not known is whether this acute bronchial inflammation has any significance in the long-term. The presence of bronchial inflammation may be a result of propylene glycol having a respiratory irritant effect. But this does not necessarily mean that long-term exposure would lead to any adverse effect on lung function. More research is necessary to clarify that point.

The authors acknowledge this: "We must state though that while the differences within our study are of statistical significance, the clinical changes may be too small to be of major clinical importance."

Despite this, ANR tells the public not only that vaping impairs acute lung function, but that it can cause difficulty breathing. This is an outright lie. There is absolutely no evidence that vaping causes clinical respiratory impairment to an extent that leads to difficulty breathing. In fact, the available evidence overwhelmingly demonstrates that smokers who switch to electronic cigarettes experience a marked improvement in their respiratory symptoms.

Unfortunately, ANR is so determined to attack electronic cigarette use that it has abandoned scientific integrity and is spreading misinformation to the public. While ANR has every right to advocate against the use of electronic cigarettes, it should not do so based on false and misleading information.

The reason I resigned from the ANR Executive Board was that the organization told me that it placed a higher value on its political objectives than on scientific integrity. This story illustrates that ANR continues to operate on this unethical strategy.

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