The use of, results from a large longitudinal cohort study demonstrated.
“For the many clinicians treating former smokers who have successfully quit all nicotine products, the implications are that use of [electronic nicotine delivery systems] should be discouraged, just as use of all other tobacco products is discouraged,” researchers led by, reported in a study published in JAMA Network Open (2020 Jun 5. ).
Dr. Everard, of the National Institute on Drug Abuse, and colleagues based their comments on results from a survey of adult former smokers who participated in Waves 1-4 of the Population Assessment of Tobacco and Health () Study (2013-2018). They limited the analysis to 2,273 former cigarette smokers who self-reported reported no tobacco product use at Wave 1, and categorized them as recent former smokers (defined as having last smoked within the past 12 previous months) or as long-term former smokers (defined as having last smoked for longer ago than in the previous 12 months). The main outcome of interest was the self-reported current use of cigarettes at follow-up interviews, which was defined as every day or some days. Electronic nicotine delivery systems (ENDS) comprised e-cigarettes, e-cigars, e-pipes, and e-hookahs. Other tobacco products included cigars, pipe tobacco, hookahs, snus tobacco, other smokeless tobacco, and dissolvable tobacco.
Of the 2,273 adult former smokers, 52% were women, 60% were older than age 50, and 80% were non-Hispanic white. Adjusted hazard ratio (AHR) analysis revealed that the use of ENDS was associated with significant risk of cigarette smoking relapse among recent former smokers (AHR 1.63) and among long-term former smokers (AHR 3.79). The use of other tobacco products was associated with significant risk for cigarette smoking relapse among recent former smokers (AHR 1.97) and among long-term former smokers (AHR 3.82).
The authors acknowledged certain limitations of the study, including the fact that it did not assess different ENDS devices, different e-liquid nicotine levels, or frequency of ENDS use and their associations with cigarette smoking relapse. It also did not explore the mechanism by which ENDS use may lead to reestablishing or reinforcing nicotine-seeking behavior among former cigarette users. “Determining pharmacologic, behavioral, or some other explanation for these findings may require laboratory-based research,” they wrote.
The PATH Study is supported with federal funds from the National Institute on Drug Abuse, the National Institutes of Health, and the Food and Drug Administration and Department of Health and Human Services under a contract to Westat. One of the study authors, Wilson M. Compton, MD, reported having long-term stock holdings in General Electric, 3M, and Pfizer. The other authors reported having no financial disclosures.