The effect of previous psychotic mood episodes on cognitive impairment in euthymic bipolar patients.
OBJECTIVE
Cognitive dysfunctions in several domains were proposed to be trait markers of bipolar patients. The aim of this study was to evaluate the effect of previous psychotic features on neuropsychological measures, including sustained attention, in remitted bipolar patients.


METHODS
The study participants were 40 euthymic psychotic, 25 non-psychotic bipolar I patients and 30 healthy control subjects. Participants were assessed with a battery of neuropsychological tests targeting attention, executive functions, psychomotor speed, verbal learning and memory.


RESULTS
Euthymic psychotic bipolar patients performed worse than controls on most of the measures, after controlling for the confounding effects of education, age and residual symptoms. Non-psychotic patients were also impaired on tasks of attention, fluency and psychomotor speed. 'Number of Wisconsin Card Sorting Test (WCST) categories' achieved was the only measure on which psychotic patients performed significantly worse compared to non-psychotic patients. Differences among patient groups were not explained by illness severity measures. The duration of illness was related to slowness in psychomotor speed tasks. Verbal memory deficits may be related to serum lithium levels and age of onset of disease.


CONCLUSIONS
Deficits in cognitive flexibility may be a candidate for being a trait marker of psychotic features among bipolar patients. However, verbal fluency, psychomotor speed and sustained attention deficits may be candidates for vulnerability indicators of bipolar disorder in general.
Affective Disorders Unit, Department of Psychiatry, Ege University School of Medicine, Izmir, Turkey. emrebora@hotmail.com
Emre
E
Bora
Simavi
S
Vahip
Fisun
F
Akdeniz
Ali Saffet
AS
Gonul
Ayse
A
Eryavuz
Melise
M
Ogut
Muge
M
Alkan
D000328:Adult; D000339:Affect; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D011618:Psychotic Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires