Moreover, despite the finding that electronic cigarettes contain only traces of tobacco-specific nitrosamines and that the level of these carcinogens is two orders of magnitude lower than in Marlboros, these "experts" are telling the public that they may be just as healthy smoking Marlboros as quitting smoking completely and using electronic cigarettes instead.
In a press release issued earlier this week entitled "Experts warn that e-cigarettes can damage the lungs," a group of researchers from the University of Athens report the results of a study of the acute effects of vaping on airways resistance in smokers with and without existing lung disease. They studied 24 smokers, 11 with normal lung function and 13 with COPD or asthma. Subjects used an electronic cigarette for 10 minutes. Airway resistance was measured before and after e-cigarette use.
The main finding was that: "In smokers with normal spirometry there was a statistically significant increase from a mean average of 176% to 220%. In COPD and asthma patients the use of one e-cigarette seemed to have no immediate effect to airway resistance."
Based on these findings the researchers concluded: "We do not yet know whether unapproved nicotine delivery products, such as e-cigarettes, are safer than normal cigarettes, despite marketing claims that they are less harmful."
The results and conclusions of the study were released to the media and the public via press release, apparently prior to peer review and publication of the study. In fact, there is no actual written study available, merely the abstract as this was an abstract presented at a scientific conference: the 2012 meeting of the European Respiratory Society.
The conclusions of the study, as disseminated by the media, were more drastic than presented in the actual abstract. Many of these headlines warned that electronic cigarette use was found to "harm the lungs," "damage the lungs," or to "cause less oxygen to be absorbed by the blood."
The Rest of the Story
Before going any further, let's correct the misrepresentation of the study findings by the media and then the misrepresentation of the study findings by the study authors.
The media claimed that the results indicate that electronic cigarettes cause "damage" to the lungs and/or cause "less oxygen to be absorbed by the blood." This is incorrect. The study found that use of an electronic cigarette for 10 minutes increased airway resistance in smokers without existing lung disease (although there was no effect on airway resistance in those with existing obstructive lung disease). A temporary increase in airway resistance does not equate to "lung damage."
For example, breathing hot, humid air has been found to increase airway resistance in some healthy subjects, but one would not claim that breathing humid air damages the lung. Obviously, a behavior such as smoking, with prolonged exposure to chemicals that cause airway inflammation can ultimately lead to lung damage and a condition of chronic obstructive lung disease with permanent increases in airway resistance that cause clinical symptoms. But a transient increase in airway resistance due to an exposure does not necessarily translate into a clinically meaningful effect, or to "harm" or "damage" to the lungs.
Even more fallacious is the claim that the study found that electronic cigarettes cause hypoxemia (lowered oxygen in the blood). The study did not even measure oxygen levels in the blood, and a small increase in airway resistance is not going to cause hypoxemia (otherwise, millions of people in Tampa would be walking around constantly with hypoxemia due to the constant heat and humidity). Tampa has other issues, but chronic hypoxemia among the majority of the population is not one of them.
Importantly, the misrepresentation of the study results regarding oxygen levels in the blood appears to be the fault of the media, as nowhere in the press release does it suggest anything about hypoxemia. However, that the media got the impression that this study demonstrates lung damage is directly attributable to the misrepresentation of the study by the authors, who titled their press release: "Experts warn that e-cigarettes can damage the lungs," rather than "Researchers warn that e-cigarettes increase airway resistance."
Readers should be aware of the fact that this finding is not new. A previous study - which was actually peer-reviewed and published - reported that electronic cigarette use can cause a mild increase in airway resistance. As I commented on that article: "The rest of the story is that a propylene-based electronic cigarette system has been shown to produce airways inflammation in users, resulting in subclinical evidence of increased airway resistance. Whether long-term use of electronic cigarettes would lead to clinical manifestations due to actual airway obstruction is unclear, and more research is necessary to make such a determination. What we do know, however, is that long-term continuation of cigarette smoking will almost certainly lead to clinically significant airway obstruction. The bottom line: if a smoker is choosing between active smoking and electronic cigarette use, the use of the electronic cigarette is clearly the wiser choice."
The same comment is relevant to the present study. Readers should be aware that in the previous study, the authors were careful to point out that their research only detected subclinical evidence of increased airway resistance and that it remained unclear whether electronic cigarettes cause any clinically significant manifestations: "We must state, however, that although the differences within our study are of statistical significance, the clinical changes may be too small to be of major clinical importance."
No such caveat is given by the authors of the present study. But the bottom line is the same. If a smoker is choosing between active smoking and electronic cigarette use, the use of the electronic cigarette is clearly the wiser choice. And in fact, this is the choice that most electronic users are facing. The idea that any substantial proportion of electronic cigarette users will quit smoking if they take the article's advice and stick to approved NRT or pharmacotherapy products is unsupported by the scientific evidence.
Although the claim that they found lung damage as a result of electronic cigarette smoking is a misrepresentation of the study findings by the authors, there is a far worse and more damaging misrepresentation. The authors, based on their finding of a possible small increase in airways resistance in some smokers, have concluded that cigarette smoking may be no more harmful than vaping. This is a sweeping conclusion that even the tobacco companies would not dare make. You would never hear a tobacco company claim that their products may be no more dangerous than inhaling nicotine and propylene glycol from a tube that contains no tobacco and involves no combustion process. However, anti-smoking researchers are making precisely that assertion.
The claim is ridiculous, damaging, and ignores all of the existing evidence. While electronic cigarettes have been shown to cause mild increases in airway resistance with uncertain clinical implications, we know that cigarette smoking causes chronic obstructive lung disease. So even if you look only at respiratory effects, there is strong evidence that smoking is more dangerous than vaping. Moreover, many vapers have experienced dramatic improvement in respiratory symptoms, which is not consistent with the argument that smoking may be no more hazardous than vaping in terms of respiratory effects.
There are no known effects of electronic cigarette use on heart disease. And the levels of tobacco-specific nitrosamines and formaldehyde (the only two carcinogens detected in electronic cigarettes) are much lower than in tobacco cigarettes. How these researchers could claim that the carcinogenic risk associated with vaping could be equivalent to that associated with cigarettes, which contain an additional 58 known carcinogens, is beyond me.
That this study was released using the "science by press release" method is also problematic. As I have argued before, scientific results should not be released to the media and the public unless either: (1) the study has been peer-reviewed and published; or (2) the entire study is made available publicly so that the work can be properly evaluated. In this case, there is no actual study I am aware of, merely an abstract. Thus, we have no way of evaluating the validity of the findings. But the results have already been widely disseminated. If the paper is subsequently peer-reviewed and the authors are told to tone down their conclusions (as I would if I were reviewing the paper), it is too late. The conclusion of these experts that vaping causes lung damage has already been disseminated. If the authors later come back and tell the media: "Sorry, we misspoke. Actually, the study only shows subclinical evidence of airway resistance and it is not clear whether this translates into any clinically meaningful effect," it will not matter. The word is already out there on the street.
In searching for a reason why the press release misrepresented the findings of the paper, the first thought that came to my mind is that perhaps there is a financial conflict of interest with Big Pharma. And indeed, it turns out that one of the study authors - Dr. Gratziou - was lead author of a study that was funded by, and conducted in part by Pfizer, maker of Chantix, a drug which stands to lose considerable sales if electronic cigarettes become popular.
Thus, this co-author of the study has a significant financial conflict of interest with Big Pharma that has the appearance of having biased the interpretation and presentation of the study findings. However, that conflict was not disclosed, either in the abstract or in the press release.
The failure to disclose this conflict of interest is inappropriate, because it essentially is hiding this important financial relationship from the public. Not only has the author been funded by Pfizer, but she has worked directly with Pfizer on the research. Thus, she has a substantial financial interest in a company whose products are a direct competitor of the product this study examines. This is a great example of why conflict of interest disclosure rules exist in the first place. It is breaches like this which led the Department of Health and Human Services to adopt a financial disclosure policy for all academic research.
The rest of the story is that the media has misrepresented the study findings, due in part to misrepresentation of the study findings by the authors themselves. Even worse, the press release disseminates a completely unsupported conclusion that runs contrary to all existing scientific evidence and which - if made by a tobacco company - would be considered fraudulent. Finally, all of this misrepresentation and deception occurs in the existence of a severe financial conflict of interest which was hidden from the media and the public.
(Thanks to Bill Godshall, Farrell Delman, Riccardo Polosa, and Dave Ryder for insights and information that have been incorporated into this commentary.)
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