Adding vaping restrictions to smoke-free air laws: associations with conventional and electronic cigarette use.

Background And Aims: In the United States, some states and localities have added vaping restrictions to established smoke-free indoor air laws in order to reduce electronic cigarette use. Yet, if smokers use e-cigarettes to quit, such restrictions could have the unintended effect of attenuating the original smoke-free air policy's effects on smoking. This study estimated changes in current smoking, past-year smoking cessation, and recent vaping following the introduction of smoke- and vape-free air laws.

Design: Observational study of nationally representative data from the 2014-2018 National Health Interview Survey.

Setting: United States.

Participants/cases: 87 334 participants, 18-54 years of age.

Measurements: Multivariable linear regressions estimated the association between increased exposure to smoke- and vape-free worksite and restaurant laws and self-reported current smoking and recent vaping among emerging adults (ages 18-25), as well as past-12-month smoking cessation among prime age adults (ages 26-54). All regressions adjusted for respondent sociodemographic and other tobacco control policies, along with state and year fixed effects.

Findings: Smoke-free worksite laws were associated with significant reductions in the likelihood of current smoking (  = - 0.050, 95% CI: -0.098, -0.002, P = 0.038) and recent vaping (  = - 0.040, 95% CI: -0.072, -0.007, P = 0.013), as well as increases in the likelihood of smoking cessation (  = 0.026, 95% CI: 0.000, 0.052, P = 0.046). Adding vaping restrictions to smoke-free worksite laws did not yield further reductions in recent vaping (  = 0.008, 95% CI: -0.021, 0.036, P = 0.568) and counteracted over half of the estimated association with current smoking relative to smoke-free policies alone (  = 0.030, 95% CI: -0.028, 0.088, P = 0.301).

Conclusions: From 2014 to 2018, increased adoption of smoke-free worksite laws in the United States was associated with reductions in both current smoking and recent vaping, as well as increases in smoking cessation. Adding vaping restrictions to smoke-free worksite laws, however, was not associated with a reduction in recent vaping among emerging adults and may have attenuated the smoke-free policy's impact on current smoking in this age group.