Background: While clean indoor air (CIA) policies are intended to reduce exposure to secondhand smoke in the workplace, restrictions in public workplaces have the potential to discourage youth smoking. There is growing evidence from cross-sectional and ecologic studies, but limited evidence from longitudinal studies that this is so. Objective – To evaluate the association between local clean indoor air (CIA) policies and smoking behaviours among Minnesota youth over time.
Design, setting, and subjects: A cohort of 4,233 Minnesota youths, ages 11 to 16 at baseline, was interviewed via telephone for six years (2000 – 2006). Individual, family, and community level variables were collected from participants every six months. A generalized estimating equation (GEE) logistic regression was used to assess the relationship between CIA policies and past-month smoking in youth over time. The analysis was controlled for potential confounders at the individual- and community-level.
Results: There was not significant association between CIA policies and youth smoking behaviours in the multivariate analyses. At the individual level, parental smoking significantly increased the odds of smoking nearly 40%, and close friend smoking increased the odds of past-month smoking by nearly 100% for each close friend. Banning smoking in the home was significantly associated with a 12% reduction in the odds of past-month smoking.
Conclusion: After accounting for other community and individual level factors known to be associated with youth smoking, there was no significant association between CIA policies and past-month smoking for youth over time.