Thursday, July 21, 2022

JAMA Research Letter Over-Reported Teen E-Cigarette Quit Attempts & Over-Prescribed a Remedy

 

The Journal of the American Medical Association in March published a research letter summarizing “Failed Attempts to Quit Combustible Cigarettes and e-Cigarettes Among US Adolescents.”  The two-page missive included a call for FDA action: “The contribution of e-cigarettes to unsuccessful nicotine quit attempts among adolescents is substantial and warrants consideration as the US formulates policies to regulate e-cigarettes.”

The authors studied nationally representative samples of 8th, 10th and 12th graders in the annual Monitoring the Future study (MTF) from 1997 to 2020.  For all years, students were asked if they had ever smoked a cigarette; those who did were then asked, “Have you ever tried to stop smoking cigarettes and found that you could not?”  In recent years, the MTF asked students if they had ever vaped nicotine; only in 2020 were they asked, “Have you ever tried to stop vaping nicotine and found that you could not?” 

I examined the 2020 data, since that was the focus of the research letter and a related University of Michigan press release.  The letter provided only a brief description of methods and analytic strategy.  So I requested additional information from the authors, and I used it to analyze the data underlying the letter’s findings.

The letter’s lead author was Richard Miech of the University of Michigan, a recognized expert on the Monitoring the Future (MTF) survey. 

The authors focused on unsuccessful attempts to quit cigarettes and e-cigarettes, but the group whose data they analyze is peculiar: all students who had ever used those products in their lifetime.  That includes a wide spectrum of students, from those who took a single puff at a party, to those who were using the products daily. 

I wanted to find out more about ever-users of these products.  Using the standard definition of past-30-day for current use among teens, I studied other survey questions to classify survey participants in the following table.  Note that more than a quarter (n=837) of e-cigarette ever users were not asked about current use.

Table 1. Cigarette and E-Cigarette Users in the 2020 MTF
UseCigarettes (n)E-Cigarettes (n)



Ever1,1913,050
Current2561,134
Non-current9321,079
Never7,8746,015
Missing/not asked3837



All9,0659,065



  

The table raises an important question about the research: Why ask the 1,079 non-current ever users if they tried to quit vaping but couldn’t?  It doesn’t matter if they answered yes or no.  The fact that they had not used the products in the last month makes the question and the answers irrelevant.

Now let’s look at the 1,134 current e-cigarette users in greater detail.  First, how frequently did they use e-cigarettes:

Table 2. Trys/Fails Among Past Month Users of E-Cigarettes in the 2020 MTF
Past Month Use (days)% Never Tried (n)% Tried/Failed (n)



1-237% (334)13% (30)
3-517% (152)11% (25)
6-912% (107)11% (24)
10-1915% (142)16% (35)
20-2910% (91)27% (60)
309% (86)22% (48)



All100% (912)100% (222)



It makes sense that nearly half of the users who tried and failed to quit had used them 20+ days in the past month.  In contrast, more than half (54%) of users who never tried to quit had used e-cigarettes five times or fewer.

The numbers in red represent the 285 frequent e-cigarette users (20+ days) who are most at risk of being or becoming addicted to nicotine.  The following table contains some additional characteristics of these students:

 

Table 3. Characteristics of Frequent (20+ Day) Current E-Cigarette Users (n=285), 2020 MTF


CharacteristicPercentage


Ever smoked55%
Ever drank alcohol90%
Current alcohol69%
Ever used marijuana86%
Current marijuana60%


 

This demonstrates that frequent e-cigarette users in the 2020 MTF were also risk-takers, half of whom smoked, and most of whom drank alcohol and used marijuana.

Miech and colleagues found that “at least 1 unsuccessful quit attempt was reported by…365 respondents for e-cigarettes in 2020,” which they opined is “substantial and warrants consideration as the US formulates policies to regulate e-cigarettes.”  However, they did not report that 39% (n=143) of the failed attempts were among teens who were not current e-cigarette users.  Of the 222 current users who had made an attempt but failed, 108 used the products 20+ days in the past month (Table 2).  This number, which is only 30% of that reported by Miech et al., represents a more valid estimate of truly unsuccessful quit attempters.

Of the 1,134 current vapers in the survey, only one-quarter (n=285) were frequent and at risk for nicotine addiction.  However, over half of them had smoked cigarettes, the vast majority were ever users of alcohol and marijuana, and strong majorities were current users of those drugs (Table 3).

Although research letters can provide valuable preliminary results, they are not a substitute for a full analysis, and they should not form the basis of government policy prescriptions.

 

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