Wednesday, September 27, 2017

2016 CDC Data Shows E-Cigarette Use Declines Again

Some 7.8 million American adults used e-cigarettes in 2016, according to data from the 2016 National Health Interview Survey, the source for CDC national smoking estimates.  That is about half a million fewer than a year earlier, and 1.1 million fewer than in 2014, the first year NHIS surveyed for vaping.  As the CDC reported a month ago (here), the 2016 data indicates 3.2% adult prevalence – 3.8% (about 4.5 million) for men, and 2.6%, (about 3.2 million) for women.  

The 2.63 million former smokers who are current vapers comprised an increasing percentage of all vapers, from 22% in 2014 to 34% in 2016.  This is more evidence that smokers are using e-cigarettes to quit their habit.  As the following chart shows, 88% of former smokers currently using e-cigarettes quit in the last 5 years, suggesting that e-cigarettes played a significant role.  Meanwhile, 12% of former-smoker current-vapers quit 6+ years ago.  The CDC admits that relapse among former smokers is common (here), so health advocates should applaud these former-smokers’ choice of e-cigarettes over far more dangerous cigarettes.



As noted previously (here), the 2.6 million former smokers represent more than mere anecdotal evidence; their documented experience ought to carry substantial weight with government policymakers. 

In view of the important positive health implications of switching to smoke-free products, the number of former smokers ought to be growing faster.  Unfortunately, the sustained war on all smoke-free products is likely suppressing broader transition away from cigarettes.





Addendum, September 29:  Bill Godshall asked me to take a closer look at every-day and some-day e-cigarette use in the NHIS surveys.  Here are the results:



Number (in millions) and Prevalence (%) of Every-Day and Some-Day E-Cigarette Use in the U.S., 2014 to 2016





Every-DaySome-DayAll




20142.71 (1.1%)6.20 (2.6%)8.91 (3.7%)
20152.94 (1.2%)5.40 (2.2%)8.34 (3.4%)
20163.06 (1.3%)4.69 (1.9%)7.75 (3.2%)
 
The number of every-day e-cig users increased by 13% between 2014 and 2016.  In 2014, the proportions of current, former and never smokers were 50% / 46% / 4%.  By 2016 the proportions were 31% / 58% / 11%, indicating that more every-day e-cig users were former smokers.  
The number of some-day e-cigarette users dropped 24% from 2014 to 2016.  The proportions of current, former and never smokers in 2014 were 80% / 12% / 8%.  By 2016 the proportions were 66% / 19% / 15%.

Addendum, October 27:  The CDC reported on October 16 that the original NHIS 2016 file contained inaccurate sampling weights.  The agency released corrected weights, which have been used to update all of the numbers in this post.   




Monday, September 18, 2017

Antidote to NEJM Formaldehype Arrives at Last



In January 2015, R. Paul Jensen and colleagues created global headlines with a defective e-cigarette experiment (here).  They claimed in the New England Journal of Medicine that vapor contains “hidden” formaldehyde at far higher levels than cigarettes (here).  Their measurements required overheating or “dry-puffing” e-cigarette liquid, a process that produces such harsh (not hidden) oral sensations that the vapor is intolerable to normal consumers. 

As Churchill said, “A lie gets halfway around the world before the truth has a chance to get its pants on.”  The Jensen mischaracterization caused considerable damage, as it encouraged smokers to believe that vaping is more dangerous than smoking. 

Last week, the formaldehyde fallacy was laid bare.  Dr. Konstantinos Farsalinos and colleagues reproduced the Jensen experiment and found that “The high levels of formaldehyde emissions that were reported in [the Jensen] study were caused by unrealistic use conditions that create the unpleasant taste of dry puffs to e-cigarette users and are thus avoided.” Their work appears in Food and Chemical Toxicology (abstract here). 

Farsalinos’ group painstakingly reproduced the earlier experiment, using the same now-outdated vaping equipment that was prone to dry puffs.  First, they had experienced vapers identify at what settings the “burning” taste of a dry puff was detected: 4.2 volts, 8.0 watts.  They then used Jensen’s methods to measure formaldehyde at various voltage-power settings, seen in the chart (above) adapted from their publication.

Vapers detected dry puffs when the formaldehyde level was 100 micrograms (per 10 puffs).  Given that a microgram is one-millionth of a gram, Jensen’s formaldehyde level wasn’t hidden at all; at 380 micrograms, it was much higher than vapers could tolerate.  At lower, normal vaping power, formaldehyde was only 20 micrograms, or two-thirds that of cigarettes.

Farsalinos cautions the scientific community: “blindly testing e-cigarettes in the laboratory setting without evaluating realistic use is a serious omission that can result in misleading conclusions about the risk to consumers compared to smoking;” and such conclusions can wrongly imply “that there is little to be gained by switching to e-cigarettes.”

In response to the Jensen article in 2015, Clive Bates and Konstantinos Farsalinos published a letter in Addiction calling for its retraction (here); the demand was ignored.  The current publication is a much-needed antidote to Jensen’s seriously flawed and misleading findings.


Wednesday, September 6, 2017

Do Smokers Quit After Hospital Cessation Trials? Don’t Count on It, or Them



Do smokers lie about quitting?  A new study analyzes smokers’ self-reports of their smoking habits six months after their participation in quit-smoking clinical trials.

Several years ago, researchers recruited sick smokers at a group of hospitals – the Consortium of Hospitals Advancing Research on Tobacco, or CHART – and conducted federally-supported smoking cessation trials.  Now Taneisha Scheuermann et al. in the journal Addiction (abstract here) examine the post-trial results, focusing on levels of cotinine, a nicotine breakdown product, in trial participants’ saliva.

Hospitals in six cities provided 5,827 smoking patients with a variety of quit-smoking interventions.  Six months later, 4,206 of those subjects completed a survey, with 1,708 reporting that they had not smoked in the past seven days.  Nearly 10% of them reported using pharmaceutical nicotine, e-cigarettes or other tobacco harm reduction products in the past seven days; those subjects were among the 530 excluded from the Scheuermann analysis.  Self-described non-smokers were offered $50 to $100 in exchange for saliva samples, but only 923 participants responded; of those, 822 supplied usable samples.

Scheuermann used a standard saliva cotinine cutoff of 10 nanograms per milliliter: participants below this level were considered to be not smoking, while those at or above were still smoking.

Of the 822 participants who reported 7-day abstinence, 347 (42.2%) were dissembling, as their saliva cotinine levels indicated they were smoking. 

That so many individuals failed to quit evidences a fact that tobacco prohibitionists often ignore: The vast majority of smokers are unable or unwilling to quit.  The 475 verified quitters constituted roughly 8% of the 5,827 patients who started the trials – a percentage that is consistent with the quit rate among the general population.  Also note that these smokers were recruited during a hospitalization, when their focus on health issues might have increased their motivation to quit.

Treating smokers as social outcasts may influence their decision to lie about the results of their quit attempts.

The CHART study was supported from 2009 to 2014 by five NIH grants costing taxpayers $15.5 million.