title: Association of anxiety disorders with the risk of smoking behaviors: a meta-analysis of prospective observational studies.
abstract: OBJECTIVE
  Published articles reported controversial results about the association of anxiety disorders with the risk of smoking behaviors. A meta-analysis was performed to assess this association between anxiety disorders and smoking behaviors.
  
  
  METHODS
  A comprehensive search was performed to identify prospective observational studies (from January, 1990 to March, 2014) of the aforementioned association. The Q test and I(2) statistic were used to examine between-study heterogeneity. Fixed or random effect model was selected based on heterogeneity test among studies. Meta-regression and the "leave one out" sensitive analysis were used to explore potential sources of between-study heterogeneity. Publication bias was estimated using Egger's regression asymmetry test.
  
  
  RESULTS
  Fifteen articles were included. After excluding studies that were the key contributors to between-study heterogeneity, the meta-analysis showed a significant association of anxiety disorders with increased risk of regular smoking (OR = 1.41, 95% CI: 1.23-1.62) and nicotine dependence (OR = 1.58, 95% CI: 1.45-1.73). No significant influence and publication bias were observed both before and after excluding the key contributors to heterogeneity.
  
  
  CONCLUSIONS
  This meta-analysis suggested that anxiety disorders had significant positive effect on the risk of smoking behaviors. This association needs to be confirmed by further studies.
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, Jinan 250012, Shandong, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, Jinan 250012, Shandong, PR China.
authors.forename: Suyun
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, Jinan 250012, Shandong, PR China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Pan
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, Jinan 250012, Shandong, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, Jinan 250012, Shandong, PR China. Electronic address: jiachongqi@sdu.edu.cn.
authors.forename: Chongqi
authors.initials: C
authors.lastname: Jia
mesh_terms: D001008:Anxiety Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D006801:Humans; D064887:Observational Studies as Topic / Q000379:methods; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology* / Q000523:psychology*
keywords: Anxiety; Meta-analysis; Nicotine dependence; Smoking