Monday, September 22, 2014

New Study Claims to Have Found that E-Cigarettes are Unhelpful in Smoking Cessation among Cancer Patients

A new study published online ahead of print in the journal Cancer reports that e-cigarettes are not helpful for smoking cessation among patients with cancer.

(See: Borderud SP, Li Y, Burkhalter JE, Sheffer CE, Ostroff JS. Electronic cigarette use among cancer patients: Characteristics of e-cigarette users and their smoking cessation outcomes. Cancer. Published online ahead of print on September 22, 2014. doi: 10.1002/cncr.28810.)

The study enrolled 1,074 patients with cancer who were smokers and were therefore referred to a tobacco treatment program at a comprehensive cancer center during the years 2012 and 2013. Smoking status, nicotine dependence, and e-cigarette use was assessed at baseline and the patients were followed for six-month. The primary outcome was smoking cessation, measured as seven-day abstinence at follow-up.

The researchers reported that patients who used e-cigarettes were no more likely to have quit smoking at follow-up than patients who did not use e-cigarettes.

The study concludes that e-cigarettes are not helpful for smoking cessation among cancer patients.

The press release announcing the study results is titled "E-Cigarettes Unhelpful in Smoking Cessation among Cancer Patients."

These results were widely publicized in the media, with negative headlines such as: "E-Cigarettes Don't Help Cancer Patients Quit Smoking."

The Rest of the Story

It is easy to see why this methodology is inappropriate to assess smoking cessation rates among smokers who use e-cigarettes in an attempt to quit smoking.

Suppose that there are 1000 e-cigarette users who enter the cancer center with a diagnosis of cancer. Of these, an amazing 900 were able to quit smoking. However, 100 were very resistant smokers and could not quit smoking, even with e-cigarettes. Note that it would be these 100 resistant smokers who would be enrolled in the study. The 900 ex-smokers who quit using e-cigarettes would not be eligible for the study, because they no longer smoke.

Now, if those 100 resistant smokers were then followed for six months, we would expect that very few of them would quit smoking because all of them had already tried e-cigarettes and failed.

In other words, the blatant flaw in this study is that it enrolled smokers who had already made quit attempts using e-cigarettes in the past. By definition, this resulted in a sample of smokers who were more resistant to quitting. One would expect to find lower quitting rates among this population of e-cigarette users.

To be valid, the study needs to examine e-cigarette smokers who have not tried these products before and are trying them for the first time in an attempt to quit smoking. Otherwise, the study cannot truly claim to draw conclusions about how helpful e-cigarettes are for smoking cessation among cancer patients.

These flaws are also noted by Dr. Robert West, director of tobacco research at University College London, who pointed out that: "the study was not able to assess whether or not for cancer patients who smoke using an e-cigarette to try and quit is beneficial "because the sample could consist of e-cigarette users who had already failed in a quit attempt, so all those who would have succeeded already would be ruled out"."

Peter Hajek, director of the Tobacco Dependence Research Unit at Queen Mary, University of London, also noted this critical flaw in the study: ""The authors followed up smokers who tried e-cigarettes but did not stop smoking, and excluded smokers who tried e-cigarettes and stopped smoking," he said. "Like smokers who fail with any method, these were highly dependent smokers who found quitting difficult. The authors concluded that e-cigarette (use) was not helpful, but that would be true for any treatment however effective if only treatment failures were evaluated."

Once again, shoddy research by opponents of electronic cigarettes has led to a situation where false conclusions are being disseminated widely to the media and the public. Most unfortunately, damage is being done to the public's health because news headlines like this are likely to dissuade many smokers from trying to quit using e-cigarettes. Of course, this means they will continue smoking the toxic real ones.

It's not clear to me why researchers who oppose electronic cigarettes are so anxious to condemn these products that they are willing to use inappropriate research designs to fulfill such an aim.

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