Extreme attributions predict the course of bipolar depression: results from the STEP-BD randomized controlled trial of psychosocial treatment.

OBJECTIVE

Little is known about predictors of recovery from bipolar depression or moderators of treatment response. In the present study, we investigated attributional style (a cognitive pattern of explaining the causes of life events) as a predictor of recovery from episodes of bipolar depression and as a moderator of response to psychotherapy for bipolar depression.

METHOD

106 depressed outpatients with DSM-IV bipolar I or II disorder who were enrolled in the Systematic Treatment Enhancement Program for Bipolar Disorder were randomly assigned to intensive psychotherapy for depression (n = 62) or to collaborative care (n = 44), a minimal psychoeducational intervention. The primary outcome was recovery status at each study visit as measured by the Clinical Monitoring Form. Attributional style was measured at baseline using the Attributional Style Questionnaire. Data were collected between 1998 and 2005.

RESULTS

All analyses were by intention to treat. Extreme attributions predicted a lower likelihood of recovery (P < .01; OR = 0.93; 95% CI, 0.88-0.98) and longer time until recovery (P < .01; OR = 0.96; 95% CI, 0.93-0.99), independent of the effects of initial depression severity. Among individuals with more pessimistic attributional styles, higher initial depression severity predicted a lower likelihood of recovery (P = .01; OR = 0.64; 95% CI, 0.45-0.91) and longer time until recovery (P < .001; OR = 0.76; 95% CI, 0.66-0.88). There was no difference in recovery rates between intensive psychotherapy and collaborative care (OR = 0.90; 95% CI, 0.40-2.01) in the full sample.

CONCLUSIONS

These results suggest that extreme, rigid attributions may be associated with a more severe course of depression and that evaluating attributional style may help clinicians to identify patients who are at risk for experiencing a more severe course of depression.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00012558.