Neuropsychological functioning across different states of bipolar disorder: Mania, hypomania and depression

Abstract

Aim: The aim of the study was to compare neuropsychological functioning across different states of bipolar disorder: mania/hypomania and depression. Method: Cognitive functions were examined in 30 patients with bipolar disorder aged 18-68 who fulfilled DSMIV criteria for a depressive episode (Hamilton Depression Rating Scale score ≥11) and 30 patients aged 23- 68 who fulfilled DSM-IV criteria for a manic or hypomanic episode (Young Mania Rating Scale ≥11). The comparison group consisted of 30 healthy individuals aged 23-71 with no history of psychiatric or neurological disorders. A neuropsychological battery assessed executive functions and fluency, working memory and attention, psychomotor speed and reaction time. Results: Patients with bipolar disorder showed cognitive dysfunctions in working memory, fluency, attention, psychomotor speed and reaction time in relation to the comparison group. The manic/hypomanic group showed impairment on the Wisconsin Card Sorting Test (WCST), a measure of executive functions, which was not observed in depressive patients. Manic/hypomanic patients had a significantly greater impairment of executive functions than the depressed patients. Discussion: The results of this study are partly consistent with the results of previous studies in this area. Conclusions: A poorer neuropsychological performance was observed in different states of bipolar disorder but in the manic/hypomanic state the cognitive deficits associated with executive functions were more serious.