title: Changes in prevalence of depression and anxiety following smoking cessation: results from an international cohort study (ATTEMPT).
abstract: BACKGROUND
  Smoking cessation improves physical health but it has been suggested that in vulnerable individuals it may worsen mental health. This study aimed to identify the short- and longer-term effects of stopping smoking on depression and anxiety in the general population and in those with a history of these disorders.
  
  
  METHODS
  Sociodemographic and smoking characteristics, and mental and physical health were assessed using established measures in the ATTEMPT cohort, an international longitudinal study of smokers (n = 3645). Smokers who had stopped for at least 3 months or less than 3 months at the 12-month follow-up were compared with current smokers (n = 1640).
  
  
  RESULTS
  At follow-up, 9.7% [95% confidence interval (CI) 8.3-11.2] of smokers had stopped for less than 3 months and 7.5% (95% CI 6.3-8.9) for at least 3 months. Compared with current smokers, prevalence of depression prescriptions obtained in the last 2 weeks was lower for those who had stopped for less than 3 months [odds ratio (OR) 0.37, 95% CI 0.14-0.96] or at least 3 months (OR 0.25, 95% CI 0.06-0.94) after adjusting for baseline prescription levels and confounding variables. Adjusted prevalence of recent depression symptoms was also lower for ex-smokers who had stopped for less than 3 months (OR 0.34, 95% CI 0.15-0.78) or at least 3 months (OR 0.24, 95% CI 0.09-0.67) than among continuing smokers. There was no change in anxiety measures in the general population or any increase in anxiety or depression symptoms in ex-smokers with a past history of these conditions.
  
  
  CONCLUSIONS
  Smoking cessation does not appear to be associated with an increase in anxiety or depression and may lead to a reduced incidence of depression.
authors.affiliation: Department of Epidemiology and Public Health, University College London, London, UK.
authors.forename: L
authors.initials: L
authors.lastname: Shahab
authors.forename: S
authors.initials: S
authors.lastname: Andrew
authors.forename: R
authors.initials: R
authors.lastname: West
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000453:epidemiology* / Q000523:psychology; D002170:Canada / Q000453:epidemiology; D016022:Case-Control Studies; D015331:Cohort Studies; D003866:Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012907:Smoking / Q000523:psychology; D016540:Smoking Cessation / Q000523:psychology / Q000706:statistics & numerical data*; D013030:Spain / Q000453:epidemiology; D006113:United Kingdom / Q000453:epidemiology; D014481:United States / Q000453:epidemiology