E-cigarette use 1 year later in a population-based prospective cohort.
Population prevalence estimates of electronic nicotine delivery system (ENDS) use range considerably based on the operational definition of 'use'. Recently, we investigated the utility of 'use frequency' for restricting prevalence estimates to non-experimenters in adult populations. Results suggested that individuals reporting use on ≤5 days in the past 30 were likely to discontinue use, and should be excluded from estimates of population prevalence.



This study investigated the predictive validity of ENDS use frequency as a measure for likelihood of continued use, and cigarette smoking abstinence.



We recontacted smokers and recent quitters who participated in the random digit dial 2014 Minnesota Adult Tobacco Survey. At ∼1 year follow-up, we reassessed ENDS use and cigarette smoking among N=601 respondents.



Fewer than half of respondents who reported using ENDSs on 1-5 days in the past 30 at baseline reported any ENDS use 1 year later (27%, 95% CI (18% to 40%)). Conversely, more than half of respondents who reported daily use at baseline also reported subsequent use at follow-up (89%, 95% CI (78% to 100%)). The likelihood of subsequent ENDS use by respondents using ENDSs on more than 5 days but less than daily did not significantly differ from chance (37%, 95% CI (22% to 61%)).



For adult population surveillance surveys, defining current use prevalence as 'any use in the past 30 days' includes many individuals who can be expected to discontinue use within 1 year. Until measures of ENDS use become standardised, researchers should choose definitions carefully because different definitions are likely to yield different results.
The Schroeder Institute for Tobacco Research and Policy Studies at Truth Initiative, Washington DC, USA.|ClearWay Minnesota, Minneapolis, Minnesota, USA.
Michael S
MS
Amato
ClearWay Minnesota, Minneapolis, Minnesota, USA.
Raymond G
RG
Boyle
Georgetown Lombardi Comprehensive Cancer Center, Washington DC, USA.
David
D
Levy
D000293:Adolescent; D000328:Adult; D000368:Aged; D000073865:Cigarette Smoking / Q000453:epidemiology*; D015331:Cohort Studies; D066300:Electronic Nicotine Delivery Systems; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D016540:Smoking Cessation / Q000706:statistics & numerical data*; D000072137:Vaping / Q000706:statistics & numerical data*; D055815:Young Adult
Electronic nicotine delivery devices; Non-cigarette tobacco products; Public policy; Surveillance and monitoring