a1 Psychiatric and Neurodevelopmental Genetics Unit, Center for Human Genetic Research, and Psychiatric Genetics Program in Mood and Anxiety Disorders, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
a2 Department of Psychiatry, University of Cambridge, Cambridge, UK
a3 Cambridge Cognition Limited, Cambridge, UK
a4 Bipolar Clinical and Research Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
a5 Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA
a6 Department of Psychiatry, University of Pittsburgh School of Medicine and Graduate School of Public Health, WPIC, Pittsburgh, PA, USA
a7 Department of Psychiatry, UCLA Semel Institute, UCLA School of Medicine, Los Angeles, CA, USA
Background Some personality characteristics have previously been associated with an increased risk for psychiatric disorder. Longitudinal studies are required in order to tease apart temporary (state) and enduring (trait) differences in personality among individuals with bipolar disorder (BD). This study aimed to determine whether there is a characteristic personality profile in BD, and whether associations between BD and personality are best explained by state or trait effects.
Method A total of 2247 participants in the Systematic Treatment Enhancement Program for Bipolar Disorder study completed the NEO Five-Factor Inventory administered at study entry, and at 1 and 2 years.
Results Personality in BD was characterized by high neuroticism (N) and openness (O), and low agreeableness (A), conscientiousness (C) and extraversion (E). This profile was replicated in two independent samples, and openness was found to distinguish BD from major depressive disorder. Latent growth modeling demonstrated that manic symptoms were associated with increased E and decreased A, and depressed symptoms with higher N and lower E, A, C and O. During euthymic phases, high N and low E scores predicted a future depression-prone course.
Conclusions While there are clear state effects of mood on self-reported personality, personality variables during euthymia predict future course of illness. Personality disturbances in extraversion, neuroticism and openness may be enduring characteristics of patients with BD.
(Received July 28 2010)
(Revised October 28 2010)
(Accepted October 29 2010)
(Online publication December 07 2010)