Positive perceptions of electronic cigarettes relative to combustible cigarettes are associated with weaker support for endgame policies on combustible cigarettes: A population-based cross-sectional study in Hong Kong.

Introduction: Positive perceptions of electronic cigarettes (e-cigarettes) relative to combustible cigarettes (CCs) may erode support for endgame policies on CCs through smoking renormalization (increasing public acceptance of smoking). We investigated the associations between perceptions of e-cigarettes relative to CCs and support for endgame policies on CCs in Hong Kong.

Methods: Adult respondents (N=2004) were surveyed using landline random digit dialing in 2015. Perceived relative harm and relative addictiveness of e-cigarettes were combined as an overall perception of e-cigarettes relative to CCs with 5 levels and we analyzed individually 'neutral/positive/mixed/unknown' perceptions against the 'negative' perception. Five individual items with dichotomous responses assessed the support for endgame policies on CCs. Support for banning the sale/use of CCs (yes/no) was also assessed. Multivariable regressions yielded adjusted odds ratios (AORs) of supporting endgame policies (individual policy items, all 5 policy items, at least 1 policy item, banning the sale/use of CCs) in relation to perceptions of e-cigarettes relative to CCs, adjusting for age, education attainment, marital status, CC smoking status and ever e-cigarette use.

Results: Support for individual endgame policy items (from 51.8% to 80.0%), banning the sale (63.8%) and use (67.5%) of CCs were generally high. Few respondents perceived e-cigarettes as more harmful (16.6%) or more addictive (9.3%) than CCs. Positive perceptions of e-cigarettes (24.0%) were associated with less support for 'ban CC sales in 10 years if there is a product providing nicotine not made from tobacco' (AOR=0.62, 95% CI: 0.40-0.97), 'ban CC use when it's prevalence falls below 5%' (AOR=0.66, 95% CI: 0.44-0.98) and 'banning the sale of CCs' (AOR=0.63, 95% CI: 0.42-0.94).

Conclusions: Positive perceptions of e-cigarettes relative to CCs were associated with less support for endgame policies on CCs in Hong Kong. Public health actions are needed to disseminate evidence-based knowledge of e-cigarettes.