title: Personality and risk of Alzheimer's disease: new data and meta-analysis.
abstract: BACKGROUND
  We examine whether broad factors and specific facets of personality are associated with increased risk of incident Alzheimer's disease (AD) in a long-run longitudinal study and a meta-analysis of published studies.
  
  
  METHODS
  Participants (n = 1671) were monitored for up to 22 years from a baseline personality assessment. The meta-analysis pooled results from up to five prospective studies (n = 5054).
  
  
  RESULTS
  Individuals with scores in the top quartile of neuroticism (hazard ratio = 3.1; 95% confidence interval = 1.6-6.0) or the lowest quartile of conscientiousness (hazard ratio = 3.3; 95% confidence interval = 1.4-7.4) had a threefold increased risk of incident AD. Among the components of these traits, self-discipline and depression had the strongest associations with incident AD. The meta-analysis confirmed the associations of neuroticism (P = 2 × 10(-9)) and conscientiousness (P = 2 × 10(-6)), along with weaker effects for openness and agreeableness (P < .05).
  
  
  CONCLUSIONS
  The current study and meta-analysis indicate that personality traits are associated with increased risk of AD, with effect sizes similar to those of well-established clinical and lifestyle risk factors.
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA; Florida State University College of Medicine, Tallahassee, FL, USA. Electronic address: antonio.terracciano@med.fsu.edu.
authors.forename: Antonio
authors.initials: A
authors.lastname: Terracciano
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA; Florida State University College of Medicine, Tallahassee, FL, USA.
authors.forename: Angelina R
authors.initials: AR
authors.lastname: Sutin
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: An
authors.affiliation: Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: O'Brien
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Alan B
authors.initials: AB
authors.lastname: Zonderman
authors.affiliation: National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Resnick
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000544:Alzheimer Disease / Q000453:epidemiology / Q000523:psychology; D008137:Longitudinal Studies; D009483:Neuropsychological Tests; D010551:Personality; D010555:Personality Inventory
keywords: APOE; Alzheimer's disease; Anxiety; Conscientiousness; Dementia; Depression; Meta-analysis; Neuroticism; Observational prospective study; Order; Self-discipline