title: Personality and smoking: individual-participant meta-analysis of nine cohort studies.
abstract: OBJECTIVE
  To investigate cross-sectional and longitudinal associations between personality and smoking, and test whether socio-demographic factors modify these associations.
  
  
  METHODS
  Cross-sectional and longitudinal individual-participant meta-analysis.
  
  
  METHODS
  Nine cohort studies from Australia, Germany, the United Kingdom and the United States.
  
  
  METHODS
  A total of 79 757 men and women (mean age = 50.8 years).
  
  
  METHODS
  Personality traits of the five-factor model (extraversion, neuroticism, agreeableness, conscientiousness and openness to experience) were used as exposures. Outcomes were current smoking status (current smoker, ex-smoker and never smoker), smoking initiation, smoking relapse and smoking cessation. Associations between personality and smoking were modelled using logistic and multinomial logistic regression, and study-specific findings were combined using random-effect meta-analysis.
  
  
  RESULTS
  Current smoking was associated with higher extraversion [odds ratio per 1 standard deviation increase in the score: 1.16; 95% confidence interval (CI) = 1.08-1.24], higher neuroticism (1.19; 95% CI = 1.13-1.26) and lower conscientiousness (95% CI = 0.88; 0.83-0.94). Among non-smokers, smoking initiation during the follow-up period was predicted prospectively by higher extraversion (1.22; 95% CI = 1.04-1.43) and lower conscientiousness (0.80; 95% CI = 0.68-0.93), whereas higher neuroticism (1.16; 95% CI = 1.04-1.30) predicted smoking relapse among ex-smokers. Among smokers, smoking cessation was negatively associated with neuroticism (0.91; 95% CI = 0.87-0.96). Socio-demographic variables did not appear to modify the associations between personality and smoking.
  
  
  CONCLUSIONS
  Adult smokers have higher extraversion, higher neuroticism and lower conscientiousness personality scores than non-smokers. Initiation into smoking is associated positively with higher extraversion and lower conscientiousness, while relapse to smoking among ex-smokers is associated with higher neuroticism.
authors.affiliation: Institute of Behavioural Sciences, University of Helsinki, Finland.
authors.forename: Christian
authors.initials: C
authors.lastname: Hakulinen
authors.affiliation: Institute of Behavioural Sciences, University of Helsinki, Finland.|Unit of Psychology, Faculty of Education, University of Oulu, Finland.
authors.forename: Mirka
authors.initials: M
authors.lastname: Hintsanen
authors.affiliation: MRC Integrative Epidemiology Unit, UK Centre for Tobacco and Alcohol Studies, and School of Experimental Psychology, University of Bristol, UK.
authors.forename: Marcus R
authors.initials: MR
authors.lastname: Munafò
authors.affiliation: Finnish Institute of Occupational Health, Helsinki, Finland.
authors.forename: Marianna
authors.initials: M
authors.lastname: Virtanen
authors.affiliation: Department of Epidemiology and Public Health, University College London, UK.|Department of Public Health, Faculty of Medicine, University of Helsinki, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Kivimäki
authors.affiliation: Department of Epidemiology and Public Health, University College London, UK.|Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, UK.|Alzheimer Scotland Dementia Research Centre, University of Edinburgh, UK.
authors.forename: George David
authors.initials: GD
authors.lastname: Batty
authors.affiliation: Institute of Behavioural Sciences, University of Helsinki, Finland.
authors.forename: Markus
authors.initials: M
authors.lastname: Jokela
mesh_terms: D000328:Adult; D000368:Aged; D001008:Anxiety Disorders / Q000523:psychology*; D001315:Australia; D003430:Cross-Sectional Studies; D005120:Extraversion, Psychological; D005260:Female; D005858:Germany; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D000075384:Neuroticism; D016017:Odds Ratio; D010551:Personality; D012907:Smoking / Q000523:psychology*; D016540:Smoking Cessation / Q000523:psychology*; D006113:United Kingdom; D014481:United States
keywords: Cohort study; five-factor model; meta-analysis; personality; smoking