Impulsivity and phase of illness in bipolar disorder

Impulsivity is prominent in bipolar disorder, but there is little quantitative information relating it to phase of illness.

We measured impulsivity in patients with bipolar disorder who had not met episode criteria for at least 6 months, patients who were manic, and healthy control subjects. Impulsivity was measured using the Barratt Impulsiveness Scale (BIS) and performance on the computerized Immediate Memory-Remote Memory Task (IMT-DMT), based on the Continuous Performance Test, which has been shown to reflect risk of impulsivity in other populations.

BIS scores in euthymic and manic bipolar subjects were identical, and were significantly elevated compared to controls. Commission errors (impulsive responses) on the IMT-DMT were elevated in manic subjects but were identical to controls in euthymic subjects. Measures of impulsivity did not appear related to depressive symptoms.

The number of subjects was too small for detailed investigation of the role of comorbidities; subjects were receiving pharmacological treatments.

Impulsivity has state- and trait-related aspects in bipolar disorder.