Dysfunctional assumptions in bipolar disorder.

BACKGROUND

Despite the initial encouraging outcome in developing CBT for bipolar affective disorder [Arch. Gen. Psychiatry 2002 (in press); Psychol. Med. 31 (2001) 459-467], very little is known about whether there are any differences in dysfunctional attitudes between unipolar and bipolar patients. Both the behavioural activation system theory [J. Pers. Soc. Psychol. 67 (1994) 488-498; Major Theories of Personality Disorder, Guilford Press, New York, 1996; Psychol. Bull. 117 (1995) 434-449] and the cognitive model for bipolar affective disorder [Cognitive Therapy for Bipolar Disorder: A Therapist's Guide to Concepts, Methods and Practise, Wiley, New York, 1999] postulate high goal striving as a risk factor for bipolar disorder. However, the existing subscales in the dysfunctional attitude scale (DAS) were derived from patients and relatives of patients suffering from unipolar depression, patients with a mixed psychiatric diagnosis or normal controls. None of the existing subscales reflects high goal striving beliefs. Using a sample of bipolar patients may yield different factors.

METHODS

A total of 143 bipolar 1 patients filled in the short version of DAS 24. Principal component analysis was carried out to derive factors. The scores of these factors were compared with those of 109 unipolar patients to investigate if these factors distinguish bipolar patients from unipolar patients.

RESULTS

Three factors were derived: factor 1 'Goal-attainment' accounted for 25.0% of the total variance. Factor 2 'Dependency' accounted for 11.0% of the total variance. Factor 3 'Achievement' accounted for 8.2% of the total variance. However, factor 1 appeared to consist of items that made a coherent theoretical construct. No significant differences were found when the validation sample was compared with 109 patients suffering from unipolar depression in any of the three factors. When subjects who were likely to be in a major depressive episode were excluded, the scores of bipolar patients (n=49) were significantly higher than euthymic unipolar patients (n=25) in factor 1 'Goal attainment'. Goal-attainment also correlated with the number of past hospitalisations due to manic episodes and to bipolar episodes as a whole.

CONCLUSIONS

The Goal-attainment subscale captures the risky attitudes described by the behavioural activation system theory and the cognitive model for bipolar affective disorder. It is postulated that these beliefs may interact with the illness and predispose bipolar patients to have a more severe course of the illness.