Another big well-done study shows e-cigarette use associated with more progression to smoking and less quitting

On January 11, 2016 Gerhard Gmel and colleagues published a very well done longitudinal study of the relationship between e-cigarette and cigarette use in 5128 Swiss male 20 year olds.
They recruited subjects when they were registering for military service (required of all 20 year old males in Switzerland) and followed them up a year later.
The authors measured smoking behavior at the beginning and the end and e-cig use at the end. 
(Yes, I know our friends in England will criticize only measuring e-cigarette use at the end.  The authors of the paper discuss this issue and we showed that when e-cig use is measured does not affect the results.)
They found:

  • Nonsmokers at baseline who used ecigs were more likely to be smokers one year later than nonsmokers who did not use e-cigs
  • Smokers at baseline who used e-cigs were less likely to have quit smoking a year later

Consistent with other studies, smokers who used e-cigs were making more quit attempts.  So the marketing claim that e-cigs help people quit is being heard but the effect of using e-cigs is less, not more, quitting.
The authors analyzed daily and occasional smokers separately and found similar effects.  They also controlled for level of nicotine dependence at baseline as well as several demographic variables.  One of the interesting results is that including these covariates did not substantially affect the overall estimates of the effects of e-cig use, which is more evidence that all the details that e-cig advocates use to dismiss the accumulating evidence are not important.
The full paper, “E-cigarette use in young Swiss men: is vaping an effective way of reducing or quitting smoking?,” is available for free here.
Here is the abstract:

QUESTION UNDER STUDY: To test longitudinally differences in conventional cigarette use (cigarettes smoked, cessation, quit attempts) between vapers and nonvapers.
METHODS: Fifteen months follow-up of a sample of 5 128 20-year-old Swiss men. The onset of conventional cigarette (CC) use among nonsmokers, and smoking cessation, quit attempts, changes in the number of CCs smoked among smokers at baseline were compared between vapers and nonvapers at follow-up, adjusted for nicotine dependence.
RESULTS: Among baseline nonsmokers, vapers were more likely to start smoking at follow-up than nonvapers (odds ratio [OR] 6.02, 95% confidence interval [CI] 2.81, 12.88 for becoming occasional smokers, and OR = 12.69, 95% CI 4.00, 40.28 for becoming daily smokers). Vapers reported lower smoking cessation rates among occasional smokers at baseline (OR = 0.43 (0.19, 0.96); daily smokers: OR = 0.42 [0.15, 1.18]). Vapers compared with nonvapers were heavier CC users (62.53 vs 18.10 cigarettes per week, p <0.001) and had higher nicotine dependence levels (2.16 vs 0.75, p <0.001) at baseline. The number of CCs smoked increased between baseline and follow-up among occasional smokers (b = 6.06, 95% CI 4.44, 7.68) and decreased among daily smokers (b = –5.03, 95% CI –8.69, –1.38), but there were no differential changes between vapers and nonvapers. Vapers showed more quit attempts at follow-up compared with nonvapers for baseline occasional smokers (incidence rate ratio [IRR] 1.81, 95% CI 1.24, 2.64; daily smokers IRR 1.28, 95% CI 0.95, 1.73).
CONCLUSIONS: We found no beneficial effects of vaping at follow-up for either smoking cessation or smoking reduction.

My one quibble with the paper is that it does not just find “no beneficial effects.”  It finds harm.
The full citation is:  Gmel G, Baggio S, Mohler-Kuo M, Daeppen JB, Studer J. E-cigarette use in young Swiss men: is vaping an effective way of reducing or quitting smoking? Swiss Med Wkly. 2016 Jan 11;146:w14271. doi: 10.4414/smw.2016.14271. eCollection 2016.


E-cig advocate's critique & Gmel et al's response worth reading

The Swiss Medical Weekly published a detailed critique of Gmel et al's well-done longitudinal study of Swiss 20 year-old men that showed that (1) smokers who used e-cigarettes were less likely to quit cigarettes than smokers who didn't use e-cigarettes, and (2) nonsmokers who started with e-cigarettes were much more likely to be smoking a year later than those who did not use e-cigarettes.
It is worth reading both the critique (available here) and the response (available here).
The critique, by Philippe Poirson, a blogger on and member of the Helvetic Vape association, makes all the same arguments that vaping enthusiasts, including the "experts" that they like to cite; Gmel et al nicely summarize these criticisms:

a) that a study among young people has to support the same conclusions as studies among older people or in the general population at all ages;
b) that an epidemiological study on general use of e-cigarettes must reach the same conclusions as smoking cessation trials among heavy smokers;
c) that data need to be broken down (heavy smokers that at some point in time become daily vapers using 3rd generation vaping tanks) until the desired effect is found;
d) and that we should overload an article by plugging in all the many analyses that he would like to see.

Gmel and colleagues, in simple language, explain why these criticisms are, at the very least, not all that important.  They also do a nice job of pointing out the extensive self-citation that e-cigarette enthusiasts engage in (while ignoring or dismissing anything that does not agree with their positions) and, importantly, the kid of non-substantive nit picking that they use to attack work they don't like.
The contribution to this back-and-forth is valuiable well beyond the specifics of the one paper under discussion.  Again, the critique is here and the response is here.

Profound Concerns Regarding Statements/Quotes Made By Louise Ro

Dear Professor Glantz,
Louise Ross is a very well-known NHS Smoking Cessation Service Manager, and soon to be a Principle Investigator of the Queen Mary University London and Barts and the London Scholl of Medicine Randomised Controlled Trial on E-cigarettes and Smoking Cessation i.e. a “scientist” and “expert” . Interestingly, also, she is now regularly a “Guest Blogger” on Clive Bates’ Counterfactual E-Cigarette advocacy site.
 I recently picked up on a quote from her, which was subsequently confirmed as being accurate from the Editor involved. One of the statements she made, that I subsequently questioned, was that she believes that e-cigarettes are: infinitely safer than a smoked cigarette”(my emphasis). Infinitely safer clearly means she believes they are safe.
 It deeply troubled me that, with no long-term data on the safety of e-cigarettes, that a front-line Smoking Cessation Professional and Investigator should make a claim such as this. I therefore wrote a response letter to the Editor of the Nursing Journal involved, questioning the scientific validity of this statement, and others that Louise Ross made in the article. I attach it for your Review.
 I am very happy for this letter to be put out on your Blog, if you think that it appropriately and usefully highlights any issues.
Yours sincerely
 David Bareham
 David W Bareham BSc Hons (Physiotherapy) MSc (Pain Management).
Specialist Respiratory Physiotherapist
Lincolnshire Community Health Services NHS Trust
Locality Office
Louth County Hospital
LN11 0EU
Dear Nursing in Practice,
I note, with great interest, this very recent Nursing in Practice (NIP) article regarding the proposed Government changes to Electronic Cigarette advertising, subsequent to new E.U. law, here:
Please may I comment on the statements made by Louise Ross (Stop Smoking Service Manager, Leicester City), which are both careless and reckless.
Louise states, according to NIP:

  1. “Advertising (e-cigarette) products widely and in a way that makes adults want to buy them is a step towards reducing smoking rates."

  2. “The more confidence the public have, and the more knowledge they have, about switching to something that is infinitely safer than a smoked cigarette, the bigger the public health gain.”

 The first point is related to a) the paramount importance that “advertising” E-Cigarettes should only target adult smokers, and b) the efficacy of electronic cigarettes in reducing smoking cessation rates.
Regarding a), in November last year, the U.K. broadcast it’s first T.V. advert for an electronic cigarette (1) which in no way targeted adult smokers, and was subsequently banned (2). So, despite clear regulations , the company concerned (which interestingly was an “Independent” e-cigarette manufacturer, as opposed to a Tobacco Manufacturer which makes e-cigarettes, such as Imperial Tobacco or British American Tobacco) made no attempt not to glamourise or overtly sexualise the devices. Criticism of the advert even came from ASH, who ardently advocate for the potential of the devices: "The VIP adverts sexualise e-cigarette use and encourage their use by everyone, not just smokers (3). Moreover, as McKee pointed out: "Experts are also particularly concerned the adverts may lead to the renormalisation of images of smoking again.” (3). If Industry in the United Kingdom, and elsewhere (4) cannot be trusted to responsibly target adult smokers with their adverts, then the much stricter rules and law, as the new European Law advocates, appears to be most appropriate. Other key data in Europe indicates that, in the real world, youth use of both electronic cigarettes AND tobacco cigarettes is increasing concurrently (5): this does not indicate that the devices are at all always displacing tobacco use, as Louise appears to suggest.
 Regarding b), as the Cochrane Review of Electronic Cigarettes (6) pointed out, even though on face value the devices appear as effective as NRT in smoking cessation, it also stated:
“There is evidence from two trials that ECs help smokers to stop smoking long-term compared with placebo ECs. However, the small number of trials, low event rates and wide confidence intervals around the estimates mean that our confidence in the result is rated 'low' by GRADE standards. The lack of difference between the effect of ECs compared with nicotine patches found in one trial is uncertain for similar reasons. ECs appear to help smokers unable to stop smoking altogether to reduce their cigarette consumption when compared with placebo ECs and nicotine patches, but the above limitations also affect certainty in this finding.”
The cessation data related to electronic cigarettes is, therefore, still in its infancy, and to therefore claim that using the devices “is a step closer to reducing smoking rates”, as Louise apparently does, is scientifically unsubstantiated. Subsequent data, published after the Cochrane Review, also provides mixed results (7):
“Daily use of e-cigarettes while smoking appears to be associated with subsequent increases in rates of attempting to quit smoking and reducing smoking, but not with smoking cessation. Non-daily use of e-cigarettes does not appear to be associated with cessation attempts, cessation or reduced smoking.”
Commentary on this data appropriately points out that:
“Taken together, this new study and the extant literature provide little empirical support for the contention that e-cig use leads reliably to smoking cessation for the majority of users.  (8)
Louise Ross, according to NIP, then makes the claim (in 2, above) that electronic cigarettes are “infinitely safer than a smoked cigarette”. This is, indeed, reckless language, as it indicates to all, including youth, that a senior NHS clinician believes that the devices ARE safe. Even “expert” opinion, drawn as it was from e-cigarette advocates, does not make this claim (9). It is reckless, as one of the factors in the spike of adolescent use of electronic cigarettes is their perception of harmlessness (10). As Wasowicz, Feleszko and Goniewicz state:
 “Young people are the most vulnerable group to initiate use of e-cigarettes. The novelty of the e-cigarette, perceptions about the harmlessness of the product, a wide variety of flavours (fruit, chocolate, peanut butter, bubble gum, gummy bear, amongst others), and peer-influence are just a few examples of factors contributing to the e-cigarette popularity among youth. The comprehensive e-cigarette regulations need to include rules on marketing, safety of newly introduced products (nicotine dosage, packaging, and labelling), marketing limitations, and banning the sale of e-cigarettes to minors.”
Goniewicz is, furthermore, a scientist central in demonstrating that electronic cigarettes do, indeed, emit significantly fewer carcinogens and toxicants than tobacco cigarettes (11). However, he and colleagues have also demonstrated that, under certain circumstances, e-cigarettes can produce specific carcinogens and toxins: in the same levels as are seen in tobacco cigarettes (12). One such toxicant, Acrolein, is produced from the heating of the E-Cigarette solvent, Glycerol. Acrolein has been identified in the urine of electronic cigarette users (13), and Acrolein is significant to our susceptible, smoking patients with Chronic Obstructive Pulmonary Disease as:
“. . . repeated exposure to lower doses represents a risk factor for development of chronic pulmonary inflammation, reduction of host defense, neutrophil inflammation,mucus hypersecretion, and protease mediated lung tissue damage. A better comprehension of the effects of acrolein in pulmonary cells may shed light on the mechanisms underlying COPD pathogenesis and pave the way for novel therapeutic approaches.” (14).
As there is no long term data on safety, we do not currently know whether electronic cigarettes merely perpetuate COPD. One small cohort study, for example, identifies no significant change in key disease indicators in patients who switch to electronic cigarettes, and no reduction in tobacco consumption (15). Other data that inform us that electronic cigarettes are not “infinitely safer” than tobacco cigarettes include those on emittance of pro-inflammatory, highly reactive free radicals (e.g. 16); increased susceptibility to infection (e.g. 17), flavourants that are associated with causing incurable lung disease (18), and potentially harmful emittance of tin and other metals (19). Indeed, the real and potential effects of these type of data were very recently highlighted by Professor John Britton (20). His slide stated that:
“Likely real and potential harms of e-cigarettes to users”
Expected modest increases in risk of:

  • Lung Cancer

  • Emphysema/COPD

  • Pulmonary Infection

  • Cardiovascular events

  • Pulmonary Fibrosis

  • (Hypersensitivity Pnuemonias)

  • Other cancers”

Preliminary data that links electronic cigarette use to both lung cancer and cancer does, indeed, exist (21;22), and furthermore, the International Agency for Research on Cancer (23) have recently noted, in regard to Electronic Cigarettes and Nicotine, that they had NOT previously evaluated electronic cigarettes and nicotine (p21). They discuss/describe current evidence, and claim that “more recent evidence has indicated the potential for nicotine to cause DNA damage”. Moreover, they continue: “In addition, exposure to nicotine has been shown to inhibit apoptosis, and stimulate cell proliferation and angiogenesis . . .”. (p22). Subsequently, they declare that an evaluation of electronic cigarettes and nicotine is a “High Priority”.
These data and opinion do not support Louise’s claim that e-cigarettes are “infinitely safer” than tobacco cigarettes. 
Yours sincerely,
David Bareham.
























David W Bareham BSc Hons (Physiotherapy) MSc (Pain Management).
Specialist Respiratory Physiotherapist
Lincolnshire Community Health Services NHS Trust
Locality Office
Louth County Hospital
LN11 0EU