Association between home smoking and e-cigarette use restrictions and concurrent use behaviors among dual users of cigarettes and e-cigarettes.

Introduction: Limited data exist on how home smoking and e-cigarette use restrictions influence patterns of cigarette and e-cigarette use among individuals who use both products. This study examined the association between home restrictions and the use of cigarettes and e-cigarettes among dual users of these two products.

Methods: We conducted a secondary analysis of data from the Adult Consumers of Tobacco Study (ACTS), an online, nationwide survey administered during 2020-2021. A sub-sample of 250 dual users of cigarettes and e-cigarettes was included in this analysis. Outcome variables were concurrent use behaviors, categorized as predominant smokers (daily smoking, e-cigarette use some days), equivalent users (either daily or some days use of both products), and predominant e-cigarette users (daily e-cigarette use, smoking some days), as well as e-cigarette use frequency (daily vs some days). Primary explanatory variables were home smoking and e-cigarette use restrictions (both categorized as complete, partial, or no restrictions). Multivariable logistic regression was used to examine associations between restrictions and concurrent use behaviors.

Results: Nearly half (46.8%) of dual users reported having complete smoking restrictions in their homes, complete e-cigarette use restrictions (12.8%), and complete restrictions on both (11.2%). Dual users reported having complete home smoking restrictions (vs no restrictions) were more than two times more likely to be predominant e-cigarette users versus equivalent users or predominant smokers (AOR=2.60; 95% CI: 1.30-5.30), after controlling for home e-cigarette use restrictions and other covariates. Neither partial smoking restrictions nor partial e-cigarette use restrictions were associated with concurrent use behaviors.

Conclusions: Small proportions of dual users reported having complete smoking and e-cigarette use restrictions adopted in their homes, suggesting a need for promoting the adoption of such restrictions. Moreover, how and why home smoking and e-cigarette use restrictions differentially impact use behaviors warrant additional investigation.