Psychological Medicine

Original Articles

Chronic stressors and trauma: prospective influences on the course of bipolar disorder

A. Gershona1 c1, S. L. Johnsona2 and I. Millera3

a1 Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA

a2 Department of Psychology, University of California, Berkeley, CA, USA

a3 Department of Psychiatry and Human Behavior, Brown University, Providence, RI, USA


Background Exposure to life stress is known to adversely impact the course of bipolar disorder. Few studies have disentangled the effects of multiple types of stressors on the longitudinal course of bipolar I disorder. This study examines whether severity of chronic stressors and exposure to trauma are prospectively associated with course of illness among bipolar patients.

Method One hundred and thirty-one participants diagnosed with bipolar I disorder were recruited through treatment centers, support groups and community advertisements. Severity of chronic stressors and exposure to trauma were assessed at study entry with in-person interviews using the Bedford College Life Event and Difficulty Schedule (LEDS). Course of illness was assessed by monthly interviews conducted over the course of 24 months (over 3000 assessments).

Results Trauma exposure was related to more severe interpersonal chronic stressors. Multiple regression models provided evidence that severity of overall chronic stressors predicted depressive but not manic symptoms, accounting for 7.5% of explained variance.

Conclusions Overall chronic stressors seem to be an important determinant of depressive symptoms within bipolar disorder, highlighting the importance of studying multiple forms of life stress.

(Received February 19 2012)

(Revised December 27 2012)

(Accepted January 11 2013)

(Online publication February 18 2013)

Key words

  • Bipolar disorder;
  • disease progression;
  • prospective studies;
  • social environment;
  • stress


c1 Address for correspondence: A. Gershon, Ph.D., Stanford University School of Medicine, Department of Psychiatry and Behavioral Sciences, 401 Quarry Road, Stanford, CA 94305-5717, USA. (Email: