Impact of vaping restrictions in public places on smoking and vaping in the United States—evidence using a difference-in-differences approach

Abstract

Aims: To estimate whether and to what extent extending indoor smoking restrictions to include electronic cigarettes (ECs) impact the use of ECs and cigarette smoking among adults in the United States. Design: Observational study using a linear probability model and applying a difference-in-differences analysis. Setting: United States. Participants: People aged 18–54 who lived in US counties where comprehensive indoor smoking laws in bars, restaurants and private work-places have been in place prior to 2010 (n = 45 111 for EC use analysis, n = 75 959 for cigarette use analysis). Measurements: Data on cigarette smoking, use of ECs and place of residence from the Tobacco Use Supplement of the Current Population Survey (TUS-CPS 2010–11, 2014–15 and 2018–19) were combined with the American Nonsmokers’ Rights Foundation (ANRF) database of state and local indoor smoking and vaping restriction laws. Findings: Indoor vaping restriction (IVR) coverage was not significantly associated with the likelihood of adult EC use [coefficient estimate = 0.001; 95% confidence interval (CI) = −0.009, 0.013, P-value = 0.783]. In addition, IVR coverage was not significantly associated with adult cigarette smoking (coefficient estimate = −0.00; 95% CI = −0.016, 0.015, P-value = 0.954). The non-significant results appeared in different socio-demographic subgroups. Conclusions: IVRs do not appear to decrease electronic cigarette use among US adults. There is no evidence that IVRs increase or decrease cigarette smoking among US adults.