July 31, 2018, 08:39 am News Staff – Users of electronic nicotine delivery systems (ENDS) who also smoke cigarettes are not more likely to quit smoking than smokers who don't use ENDS devices.
That's among findings of a study by researchers at Georgia State University's (GSU's) School of Public Health that was published July 9 in the PLOS ONE journal.
The researchers found no evidence to indicate that ENDS marketed and used in the United States are effective at helping cigarette smokers quit at a population level, even though anecdotally, some smokers have said they found ENDS useful in their cessation efforts.
The researchers conducted a population-based, prospective cohort study of a random probability sample of 1,284 U.S. adult smokers initially recruited in 2015 and recontacted a year later. The patient panel was drawn from GfK's KnowledgePanel, a probability-based web panel designed to represent noninstitutionalized U.S. adults.
This specific sample of established smokers was made up of respondents to the 2015 (August-September) Tobacco Products and Risk Perceptions Survey on their smoking and ENDS use.
Of the 1,081 baseline smokers who remained in KnowledgePanel at the one-year mark, 858 completed the follow-up survey.
The primary outcome of interest from the study was smoking abstinence for at least 30 days before follow-up. Secondary outcome variables were making a quit attempt during the 12-month study period and, for those who continued to smoke at follow-up, number of cigarettes smoked per day.
At the end of the study, researchers found that the odds of quitting smoking were lower for those who used ENDS at baseline (9.4 percent) compared with smokers who did not use ENDS (18.9 percent). The researchers also found that smokers who used ENDS daily at any point during the study were less likely to quit smoking than nonusers.
Moreover, 90 percent of "dual users" (participants who used both ENDS and traditional cigarettes at the beginning of the study) were still smoking at follow-up, according to the study's authors. Among those baseline dual users, nearly 54 percent were smoking cigarettes as well as using ENDS after a year, and more than 37 percent were still smoking cigarettes but had stopped using ENDS.
Among smokers who didn't use ENDS at baseline, 73.5 percent smoked daily compared with 70.5 percent among smokers who did use ENDS at baseline. Similarly, no statistically significant difference was seen between daily smokers who used ENDS at any point during the study and those who did not (74.7 percent and 71.4 percent, respectively).
Compared to smokers who did not use ENDS, those who used ENDS during the study period were younger (age 41.5 versus 45.1) and were more likely to recognize their addiction to smoking cigarettes (87.7 percent versus 78 percent) and report a history of psychiatric/psychological therapy (50.1 percent versus 38.2 percent).
Also of note, less than one-third of both ENDS users and nonusers (32.8 percent and 25.9 percent, respectively) said they had ever used an approved nicotine replacement therapy or pharmaceutical drug to quit smoking.
Although the researchers found that users of ENDS were more likely to try to quit smoking, this didn't translate into greater success.
For example, study participants who specifically said they were using ENDS to help stop smoking -- which was most ENDS-using respondents -- were actually less likely to quit than those who didn't use the devices.
"Many smokers are using ENDS in their smoking quit attempts, but these devices may not be providing a sufficiently satisfying nicotine delivery and overall user experience to completely supplant their smoking," said lead author Scott Weaver, Ph.D., assistant professor of epidemiology and biostatistics at GSU, in a news release.
"Coordinated regulation aimed at improving the appeal and satisfaction of ENDS available to smokers, while reducing the nicotine levels in combustible tobacco products to nonaddictive levels, may be necessary for ENDS to have a meaningful role in reducing the staggering public health burden of smoking."
The authors noted that limitations of the study included having a limited ability to draw causal inferences from the observational design and a lack of biochemical verification of quitting smoking or ENDS use. They recommended that additional research be conducted to monitor rapidly changing ENDS market and usage patterns.
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