Associations of Smoke-Free Policies in Restaurants, Bars, and Workplaces With Blood Pressure Changes in the CARDIA Study.

Background Smoke-free legislation has been associated with reductions in secondhand smoke exposure and cardiovascular disease. However, it remains unknown whether smoke-free policies are associated with reductions in blood pressure ( BP ). Methods and Results Longitudinal data from 2606 nonsmoking adult participants of the CARDIA (Coronary Artery Risk Development in Young Adults) Study (1995-2011) were linked to state, county, and local-level 100% smoke-free policies in bars, restaurants, and/or nonhospitality workplaces based on participants' census tract of residence. Mixed-effects models estimated associations of policies with BP and hypertension trajectories over 15 years of follow-up. Fixed-effects regression estimated associations of smoke-free policies with within-person changes in systolic and diastolic BP and hypertension. Models were adjusted for sociodemographic, health-related, and policy/geographic covariates. Smoke-free policies were associated with between-person differences and within-person changes in systolic BP . Participants living in areas with smoke-free policies had lower systolic BP on average at the end of follow-up compared with those in areas without policies (adjusted predicted mean differences [in mm Hg]: restaurant: -1.14 [95% confidence interval: -2.15, -0.12]; bar: -1.52 [-2.48, -0.57]; workplace: -1.41 [-2.32, -0.50]). Smoke-free policies in restaurants and bars were associated with mean within-person reductions in systolic BP of -0.85 (-1.61, -0.09) and -1.08 (-1.82, -0.34), respectively. Only restaurant policies were associated with a significant within-person reduction in diastolic BP , of -0.58 (-1.15, -0.01). Conclusions While the magnitude of associations was small at the individual level, results suggest a potential mechanism through which reductions in secondhand smoke because of smoke-free policies may improve population-level cardiovascular health.