The prevalence and effect of life events in 222 bipolar I and II patients: a prospective, naturalistic 4 year follow-up study.

BACKGROUND

Life events may very well increase the likelihood of affective episodes in bipolar disorder, but prospective data on survival are inconsistent.

METHODS

The authors examined the prevalence of negative and goal-attainment life events within 6 months prior to the index episode and after the index episode and their impact on the risk of relapse. Two hundred twenty-two consecutively admitted ICD-10 bipolar I (n=126) and II (n=96) patients were followed-up naturalistically over a period of 4 years.

RESULTS

One-hundred thirty-eight (62.2%) of the patients had at least one life event 6 month before the index episode. Seventy patients (31.5%) experienced one, 48 (21.6%) two, and 20 (9.0%) three (or more) life events. Regarding life events after the index episode, 110 (49.5%) patients had at least one life event. Fifty-four patients (24.3%) experienced one, 31 (14.0%) two, and 25 (11.3%) three (or more) life events. The number of life events was larger in patients with bipolar II disorder than in patients with bipolar I disorder (p=0.004). Using a Cox regression analysis, the risk of a depressive relapse in bipolar I patients was associated with the number of life events after the index episode (p=0.002). This was independent of the quality of the life event.

LIMITATIONS

Standardized life event scales, defined dosages of drugs or blood sampling during all visits were not performed.

CONCLUSIONS

Our data suggest a high and continuous number of life events prior to affective episodes. Life events after the index episode worsened the course of bipolar I patients with more depressive episodes. This underlines the importance of detection and treatment of emerging life events.