Time-Varying Determinants of Changes in E-Cigarette Relative Harm Perception Among US Young Adults.

BACKGROUND: Current e-cigarette use has increased among young adults in the USA despite a consistent decrease in perceiving e-cigarettes as less harmful than cigarettes over time. This study examined time-varying predictors associated with the changes in e-cigarette relative harm perception over time among US young adults. METHODS: Data were from the 2013-2018 Population Assessment of Tobacco and Health (PATH) Study for young adults (18-24 years). A time-varying effect model (TVEM) was applied to examine the association between the relative harm perception change and the associated time-varying predictors. RESULTS: Of the 8427 young adults, the prevalence of those who perceived e-cigarettes as less harmful than cigarettes decreased from 50.3% in Wave 1 (2013-2014) to 27.7% in Wave 4 (2016-2018). Young adults who were male were more likely to perceive e-cigarettes as less harmful than cigarettes over time (OR = 1.58; 95%CI, 1.53-1.64). In addition, the changes in e-cigarette relative harm perception were less noticeable among those with advanced degrees, who had non-combustible smoke-free home rules, who held negative tobacco-related attitudes, and those who were current e-cigarette users or ever used alcohol (all p values < 0.05). CONCLUSIONS: A decline was observed in US young adults who perceived e-cigarettes as less harmful than cigarettes from the PATH Study across four waves (2013-2018). The study findings underscore the importance of risk communication that focuses on harm perception profiles and the need for appropriate interventions to balance the considerations of e-cigarette use among young adults.

Perception of the relative harm of electronic cigarettes compared to cigarettes amongst US adults from 2013 to 2016: analysis of the Population Assessment of Tobacco and Health (PATH) study data.

BACKGROUND: Electronic cigarettes (e-cigarettes) have been characterised as significantly less harmful than cigarettes by many health agencies and regulators globally. In this study, we examined to what extent perceived relative harms of e-cigarettes compared to cigarettes have changed in the USA. METHODS: We analysed the data from the longitudinal and nationally representative, Population Assessment of Tobacco and Health Study to assess the relative perceived harm of e-cigarettes amongst US adults between 2013 and 2016. RESULTS: The proportion of US adults who correctly perceived e-cigarettes as less harmful than cigarettes decreased each year from 41.1% (CI 40.1-42.1%) in 2013-2014, 31.5% (CI 30.8-32.2%) in 2014-2015 and 25.3% (CI 24.6-26.0%) in 2015-2016. Concurrently, the proportion of US adults who perceived e-cigarettes as equally, or more, harmful than cigarettes increased from 53.7% (CI 52.3-55.1%), 64.9% (CI 63.6-66.2%) to 72.7% (CI 71.5-73.9%) respectively. The proportion of US adults who held negative relative harm perceptions of e-cigarettes increased regardless of current smoking or vaping status by 24.6% and 29.6% respectively within 3 years. In Wave 3, the proportion of current smokers who perceived the relative harm of e-cigarettes as less harmful was lower at 29.3% (CI 28.2-30.4%) compared to current e-cigarette users at 43.5% (CI 40.3-46.7%). Former smokers who used e-cigarettes and believed that they were equally, or more, harmful than cigarettes in 2014-2015 had significantly higher rates of smoking relapse in the following year, 29% and 37% (p < 2.2e-16), respectively, compared to those with positive relative harm perceptions who reported relapse rates of 19%. CONCLUSIONS: In this study, the proportion of US adults who incorrectly perceived e-cigarettes as equal to, or more, harmful than cigarettes increased steadily regardless of smoking or vaping status. Current adult smokers appear to be poorly informed about the relative risks of e-cigarettes yet have potentially the most to gain from transitioning to these products. The findings of this study emphasise the urgent need to accurately communicate the reduced relative risk of e-cigarettes compared to continued cigarette smoking and clearly differentiate absolute and relative harms. Further research is required to elucidate why the relative harm of e-cigarettes is misunderstood and continues to deteriorate.

Associations between absolute and relative electronic cigarette harm perceptions and information-seeking behaviours among US adult current, former and never smokers.

INTRODUCTION: Electronic cigarette (e-cigarette) harm perceptions and information seeking behaviours are both important antecedents of e-cigarette use, yet the relationship between them has been rarely studied. We assessed how absolute (e-cigarettes are harmful to my health) and relative harm perceptions (e-cigarettes are more/less harmful than cigarettes) were associated with specific e-cigarette information seeking behaviours in a sample of current, former and never cigarette smokers. METHODS: We used data from US adults in two cycles of the Health Information National Trends Survey (HINTS-FDA 2015, n = 3738; 2017, n = 1736). Analyses controlled for socio-demographics, ever e-cigarette use and survey cycle. Data were analysed between January and August 2020. RESULTS: Higher relative harm perceptions were associated with lower odds of having sought any information on e-cigarettes [adjusted odds ratio 0.61, 95% confidence interval (0.48, 0.84)] and on how to use e-cigarettes to quit smoking specifically [adjusted odds ratio 0.59, 95% confidence interval (0.38, 0.91)]. Smoking status did not moderate associations between absolute or relative harm perceptions and information seeking behaviours, nor was it associated with specific information seeking behaviours after adjusting for covariates. DISCUSSION AND CONCLUSIONS: The risks of e-cigarettes relative to combusted cigarettes (as opposed to the absolute risks of e-cigarettes) appear to be more important in individuals' information seeking behaviours about e-cigarettes. Public health messages could ensure that all individuals understand how one's health risk would change if they exclusively used e-cigarettes, switched to e-cigarettes completely or used both products.