Cognitive vulnerability in patients with bipolar disorder.

BACKGROUND: No study has simultaneously explored key components of Beck's model of cognitive vulnerability to depression in people with bipolar disorders.
METHODS: We compared 41 euthymic bipolar patients with 20 healthy control subjects. All subjects were assessed on the Hamilton Rating Scale for Depression, the Autobiographical Memory Test and the Mean Ends Problem-Solving procedure and also completed the Beck Depression Inventory, the Dysfunctional Attitude Scale, the Sociotropy Autonomy Scale and the Rosenberg Self-Esteem Questionnaire.
RESULTS: In comparison to control subjects, patients with bipolar disorder demonstrated significantly higher levels of dysfunctional attitudes (particularly perfectionism and need for approval) and sociotropy, significantly greater over-general recall on an autobiographical memory test and significantly less ability to generate solutions to social problem-solving tasks. These between group differences remained significant when age, intelligence, latency to respond to autobiographical memory test cue words, and subjective mood ratings were included as co-variates in the statistical analysis. Within the patient group, cognitive dysfunction was significantly correlated with level of morbidity (as measured by number of previous illness episodes).
CONCLUSIONS: This study suggests that cognitive vulnerability in patients with bipolar disorder is similar to that described in unipolar disorders. It is not clear whether this dysfunction is a cause or an effect of repeated episodes of bipolar disorder. However, the findings may have implications for clinical treatment as well as suggesting a number of important new avenues of research into psychological models of affective disorder.