Is exposure to e-cigarette communication associated with perceived harms of e-cigarette secondhand vapour? Results from a national survey of US adults.

Objectives: E-cigarettes are frequently advertised and portrayed in the media as less harmful compared with regular cigarettes. Earlier surveys reported public perceptions of harms to people using e-cigarettes; however, public perceptions of harms from exposure to secondhand vapour (SHV) have not been studied. We examined associations between self-reported exposure to e-cigarette advertising, media coverage, and interpersonal discussion and perceived harms of SHV.

Design: Observational study.

Setting: National online sample of US adults aged ≥18 years.

Participants: 1449 US adults (mean age 49.5 years), 51.3% female, 76.6% non-Hispanic Caucasian, 7.5% African-American, 10.0% Hispanic and 5.9% other races.

Outcomes: Perceived harm measures included (1) harmfulness of SHV to one's health, (2) concern about health impact of breathing SHV and (3) comparative harm of SHV versus secondhand smoke (SHS). Predictors were (1) self-reported frequency of exposure to e-cigarette advertising, media coverage and interpersonal discussion (close friends or family) and (2) perceived valence of exposure from each source. Covariates were demographic characteristics, cigarette smoking status and e-cigarette use, and were weighted to the general US adult population.

Results: More frequent interpersonal discussion was associated with lower perceived harmfulness of SHV to one's health and lower perceived comparative harm of SHV versus SHS. Frequency of e-cigarette ad and other media exposure were not significant predictors. Perceived negative valence of ad exposure and interpersonal discussion (vs no exposure) was associated with higher perceived harm across all three outcomes, while negative valence of media coverage was associated with higher concern about health impact of breathing SHV. Perceived positive valence (vs no exposure) of interpersonal discussion was associated with lower perceived harm across all three outcomes about health impact of breathing SHV.

Conclusions: Exposure to information about e-cigarettes through advertising, media coverage and interpersonal discussion could play a role in shaping public perceptions of the harmfulness of SHV.