Longitudinal course of bipolar I disorder: duration of mood episodes

Arch Gen Psychiatry. 2010 Apr;67(4):339-47. doi: 10.1001/archgenpsychiatry.2010.15.


Context: The phenomenology of bipolar I disorder affects treatment and prognosis.

Objective: To describe the duration of bipolar I mood episodes and factors associated with recovery from these episodes.

Design: Subjects with Research Diagnostic Criteria bipolar I disorder were prospectively followed up for as long as 25 years. The probability of recovery over time from multiple successive mood episodes was examined with survival analytic techniques, including a mixed-effects grouped-time survival model.

Setting: Five US academic medical centers.

Participants: Two hundred nineteen subjects with bipolar I disorder.

Main outcome measures: Level of psychopathology was assessed with the Longitudinal Interval Follow-up Evaluation every 6 months for the first 5 years of follow-up and annually thereafter.

Results: The median duration of bipolar I mood episodes was 13 weeks. More than 75% of the subjects recovered from their mood episodes within 1 year of onset. The probability of recovery was significantly less for an episode with severe onset (psychosis or severe psychosocial impairment in week 1 of the episode) (hazard ratio [HR] = 0.746; 95% confidence interval [CI], 0.578-0.963; P = .02) and for subjects with greater cumulative morbidity (total number of years spent ill with any mood episode) (HR = 0.917; 95% CI, 0.886-0.948; P < .001). Compared with the probability of recovery from a major depressive episode, there was a significantly greater probability of recovery from an episode of mania (HR = 1.713; 95% CI, 1.373-2.137; P < .001), hypomania (HR = 4.502; 95% CI, 3.466-5.849; P < .001), or minor depression (HR = 2.027; 95% CI, 1.622-2.534; P < .001) and, conversely, a significantly reduced probability of recovery from a cycling episode (switching from one pole to the other without an intervening period of recovery) (HR = 0.438; 95% CI, 0.351-0.548; P < .001).

Conclusions: The median duration of bipolar I mood episodes was 13 weeks, and the probability of recovery was significantly decreased for cycling episodes, mood episodes with severe onset, and subjects with greater cumulative morbidity.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Affect
  • Bipolar Disorder / psychology*
  • Depression / psychology
  • Disease Progression
  • Female
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Prospective Studies
  • Psychiatric Status Rating Scales
  • Recurrence
  • Remission, Spontaneous
  • Time Factors
  • United States