Gender influences the detection of spatial working memory deficits in bipolar disorder.
OBJECTIVE
Despite evidence that gender may influence neurocognitive functioning, few studies have examined its effects in bipolar disorder (BD) a priori. The aim of this study was to examine how gender influences executive-type functions, which are potentially useful as endophenotypes for BD.


METHODS
The performance of 26 euthymic patients (12 males, 14 females) with DSM-IV BD (20 BD type I and six BD type II) was compared to that of 26 controls (12 males, 14 females) on tests of executive function. Controls were matched to patients on an individual basis for sex, age and premorbid IQ. Tests assessed spatial working memory (SWM), planning, attentional set-shifting and verbal fluency.


RESULTS
Overall, patients showed deficits in SWM strategy (p < 0.001) and made more SWM errors relative to controls (p < 0.001). These deficits were more apparent in male-only comparisons (both p < 0.001) than in female-only comparisons (both p < 0.05). When examined in isolation, male controls were significantly better at performing the SWM task than female controls (both p < 0.05). This pattern was not observed in the patient cohort: male patients had poorer strategy scores than female patients (p < 0.05), but made a similar number of SWM errors.


CONCLUSIONS
These findings provide evidence that gender can influence the detection of SWM deficits in the euthymic phase of BD, as the sex-related disequilibrium in SWM identified in healthy controls was disrupted in BD.
Barrett
Suzanne Lucia
SL
Division of Psychiatry and Neuroscience, Queens University Belfast, Belfast, Northern Ireland, UK. s.l.barrett@qub.ac.uk
Kelly
Christopher
C
Bell
Robert
R
King
David John
DJ
D000328:Adult; D000339:Affect; D000368:Aged; D001288:Attention; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D005717:Games, Experimental; D006801:Humans; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D009949:Orientation; D010364:Pattern Recognition, Visual; D011340:Problem Solving; D011594:Psychometrics / Q000706:statistics & numerical data; D011597:Psychomotor Performance; D012737:Sex Factors