title: Secondhand smoke exposure and mental health in adults: a meta-analysis of cross-sectional studies.
abstract: OBJECTIVE
  Previous studies assessing secondhand smoke (SHS) and risk of mental health problems have yielded inconsistent results. We performed a meta-analysis to statistically assess the association between SHS exposure, depressive symptoms and psychological distress among adults.
  
  
  METHODS
  A systematically search of Pubmed (1946-2015) and EMBASE (1976-2015) was conducted and supplemented by bibliographies of all retrieved articles to find additional relevant citations. Odds ratios (OR) and associated 95 % confidence interval (CI) of each eligible study were extracted and pooled in our meta-analysis.
  
  
  RESULTS
  A total of 11 studies comprising 86,739 participants met the inclusion criteria. A random-effect model was used in meta-analysis since considerable heterogeneity was expected. Our results indicate that SHS exposure was significantly associated with depressive symptoms (OR 1.60, 95 % CI 1.35-1.90) and psychological distress (OR 1.32, 95 % CI 1.11-1.56).
  
  
  CONCLUSIONS
  Exposure to SHS among non-smoker is associated with depressive symptoms and psychological distress, emphasizing the significance of reducing SHS exposure at a population level.
authors.affiliation: Department of Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China.
authors.forename: Yan-Ni
authors.initials: YN
authors.lastname: Zeng
authors.affiliation: Department of Nursing, The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China. li_yamin3@163.com.
authors.forename: Ya-Min
authors.initials: YM
authors.lastname: Li
mesh_terms: D003430:Cross-Sectional Studies; D003863:Depression / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D008603:Mental Health; D016017:Odds Ratio; D012306:Risk; D013315:Stress, Psychological / Q000453:epidemiology*; D014028:Tobacco Smoke Pollution / Q000706:statistics & numerical data*
chemical_list: D014028:Tobacco Smoke Pollution
keywords: Depressive symptoms; Meta-analysis; Psychological disorder; Secondhand smoke