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Meta-analyses of cognitive functioning in euthymic bipolar patients and their first-degree relatives

Published online by Cambridge University Press:  09 October 2007

B. Arts ,
N. Jabben ,
L. Krabbendam  and
J. van Os
B. Arts*
Affiliation:
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, PO Box 616 (KAP2), 6200 MDMaastricht, The Netherlands
N. Jabben
Affiliation:
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, PO Box 616 (KAP2), 6200 MDMaastricht, The Netherlands
L. Krabbendam
Affiliation:
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, PO Box 616 (KAP2), 6200 MDMaastricht, The Netherlands
J. van Os
Affiliation:
Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, PO Box 616 (KAP2), 6200 MDMaastricht, The Netherlands Division of Psychological Medicine, Institute of Psychiatry, London, UK
*
*Address for correspondence: B. M. G. Arts, Department of Psychiatry and Neuropsychology, South Limburg Mental Health Research and Teaching Network, EURON, Maastricht University, PO Box 616 (KAP2), 6200 MDMaastricht, The Netherlands. (Email: b.arts@np.unimaas.nl)
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Abstract

Background

Previous work suggests that impairments in executive function and verbal memory in particular may persist in euthymic bipolar patients and serve as an indicator of genetic risk (endophenotype).

Method

A systematic review of the literature was undertaken. Effects sizes were extracted from selected papers and pooled using meta-analytical techniques.

Results

In bipolar patients, large effect sizes (d>0.8) were noted for executive functions (working memory, executive control, fluency) and verbal memory. Medium effect sizes (0.5<d<0.8) were reported for aspects of executive function (concept shifting, executive control), mental speed, visual memory, and sustained attention. Small effect sizes (d<0.5) were found for visuoperception. In first-degree relatives, effect sizes were small (d<0.5), but significantly different from healthy controls for executive function and verbal memory in particular.

Conclusions

Executive function and verbal memory are candidate bipolar endophenotypes given large deficits in these domains in bipolar patients and small, but intermediate, cognitive impairments in first-degree relatives.

Keywords

Bipolar patientscognitionmeta-analysisrelatives
Type
Review Article
Information
Psychological Medicine , Volume 38 , Issue 6 , June 2008 , pp. 771 - 785
Copyright
Copyright © Cambridge University Press 2007

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