title: Comparative Study of Personality Traits in Patients with Bipolar I and II Disorder from the Five-Factor Model Perspective.
abstract: OBJECTIVE
  The distinguishing features of Bipolar I Disorder (BD I) from Bipolar II Disorder (BD II) may reflect a separation in enduring trait dimension between the two subtypes. We therefore assessed the similarities and differences in personality traits in patients with BD I and BD II from the perspective of the Five-Factor Model (FFM).
  
  
  METHODS
  The revised NEO Personality Inventory (NEO-PI-R) was administered to 85 BD I (47 females, 38 males) and 43 BD II (23 females, 20 males) patients. All included patients were in remission from their most recent episode and in a euthymic state for at least 8 weeks prior to study entry.
  
  
  RESULTS
  BDII patients scored higher than BD I patients on the Neuroticism dimension and its four corresponding facets (Anxiety, Depression, Self-consciousness, and Vulnerability). In contrast, BD II patients scored lower than BD I patients on the Extraversion dimension and its facet, Positive emotion. Competence and Achievement-striving facets within the Conscientiousness dimension were significantly lower for BD II than for BD I patients. There were no significant between-group differences in the Openness and Agreeableness dimensions.
  
  
  CONCLUSIONS
  Disparities in personality traits were observed between BD I and BD II patients from the FFM perspective. BD II patients had higher Neuroticism and lower Extraversion than BD I patients, which are differentiating natures between the two subtypes based on the FFM.
authors.affiliation: Department of Psychiatry, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Byungsu
authors.initials: B
authors.lastname: Kim
authors.forename: Jong-Han
authors.initials: JH
authors.lastname: Lim
authors.forename: Seong Yoon
authors.initials: SY
authors.lastname: Kim
authors.forename: Yeon Ho
authors.initials: YH
authors.lastname: Joo