Secondhand Smoke Exposure Policy and the Risk of Depression in the United States

Background: The United States Surgeon General has concluded that secondhand smoke (SHS) causes premature death and disease in persons who do not smoke, and that no scientific evidence establishes a risk-free level of exposure. Studies have shown that banning smoking in work and public settings leads to immediate reductions in disease burden. However, no previous studies have looked specifically at the impact smoking bans may have on depression.

Methods: The 2006 Behavioral Risk Factor Surveillance System (BRFSS) uses ed a cross-sectional design representative of the non-institutionalized civilian US population. Never smoker survey participants 18 years of age or older were selected from the BRFSS (n=187,594) with their Self-report of depressive symptoms in the last 2 weeks as assessed by the Patient Health Questionnaire. Depression symptom scores of 10 or higher have been established to characterize major depression with 88% sensitivity and 88% specificity. Adjustment for survey design, sociodemographic status, and alcohol consumption, as well as work and home smoking policy, were considered.

Results: After adjustment, never smokers had a significantly increased risk of reporting depressive symptoms with SHS exposure at home (Odds Ratio = 2.97 [95% confidence interval = 1.68-5.25]); in public areas at work (2.39 [1.02-5.59]); and where smoking was allowed anywhere (2.65 [1.36-5.18]).

Conclusions: Findings from the present analysis strongly support policies that ban smoking in all workplace settings. Interventions designed to eliminate smoking in the home are also needed.