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High educational performance is a distinctive feature of bipolar disorder: a study on cognition in bipolar disorder, schizophrenia patients, relatives and controls

Published online by Cambridge University Press:  01 December 2015

A. Vreeker
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
M. P. M. Boks
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
L. Abramovic
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
S. Verkooijen
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
A. H. van Bergen
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
M. H. J. Hillegers
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
A. T. Spijker
Affiliation:
Department of Mood Disorders, PsyQ, The Hague, The Netherlands Department of Mood Disorder, PsyQ Rijnmond, Rotterdam, The Netherlands
E. Hoencamp
Affiliation:
Parnassia BAVO Group, The Hague, The Netherlands Leiden University, Institute of Psychology, Leiden, The Netherlands
E. J. Regeer
Affiliation:
Altrecht Institute for Mental Health Care, Utrecht, The Netherlands
R. F. Riemersma-Van der Lek
Affiliation:
Department of Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
A. W. M. M. Stevens
Affiliation:
Dimence Centre for Bipolar Disorders, Almelo, The Netherlands
P. F. J. Schulte
Affiliation:
Mental Health Services, Noord Holland Noord, Alkmaar, The Netherlands
R. Vonk
Affiliation:
Reinier van Arkel Group, ‘s-Hertogenbosch, The Netherlands
R. Hoekstra
Affiliation:
Delta Center for Mental Health Care, Rotterdam, The Netherlands
N. J. M. van Beveren
Affiliation:
Delta Center for Mental Health Care, Rotterdam, The Netherlands Department of Psychiatry, Erasmus University Medical Center, Rotterdam, The Netherlands Department of Neuroscience, Erasmus University Medical Center, Rotterdam, The Netherlands
R. W. Kupka
Affiliation:
Altrecht Institute for Mental Health Care, Utrecht, The Netherlands Department of Psychiatry, VU University Medical Center, Amsterdam, The Netherlands
R. M. Brouwer
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands
C. E. Bearden
Affiliation:
Semel Institute For Neuroscience and Human Behavior, University of California-Los Angeles, Los Angeles, California, USA Department of Psychology, University of California-Los Angeles, Los Angeles, California, USA
J. H. MacCabe
Affiliation:
Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
R. A. Ophoff
Affiliation:
Department of Psychiatry, University Medical Center Utrecht, Brain Center Rudolf Magnus, Utrecht, The Netherlands Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, University of California Los Angeles, Los Angeles, California, USA

Abstract

Background

Schizophrenia is associated with lower intelligence and poor educational performance relative to the general population. This is, to a lesser degree, also found in first-degree relatives of schizophrenia patients. It is unclear whether bipolar disorder I (BD-I) patients and their relatives have similar lower intellectual and educational performance as that observed in schizophrenia.

Method

This cross-sectional study investigated intelligence and educational performance in two outpatient samples [494 BD-I patients, 952 schizophrenia spectrum (SCZ) patients], 2231 relatives of BD-I and SCZ patients, 1104 healthy controls and 100 control siblings. Mixed-effects and regression models were used to compare groups on intelligence and educational performance.

Results

BD-I patients were more likely to have completed the highest level of education (odds ratio 1.88, 95% confidence interval 1.66–2.70) despite having a lower IQ compared to controls (β = −9.09, s.e. = 1.27, p < 0.001). In contrast, SCZ patients showed both a lower IQ (β = −15.31, s.e. = 0.86, p < 0.001) and lower educational levels compared to controls. Siblings of both patient groups had significantly lower IQ than control siblings, but did not differ on educational performance. IQ scores did not differ between BD-I parents and SCZ parents, but BD-I parents had completed higher educational levels.

Conclusions

Although BD-I patients had a lower IQ than controls, they were more likely to have completed the highest level of education. This contrasts with SCZ patients, who showed both intellectual and educational deficits compared to healthy controls. Since relatives of BD-I patients did not demonstrate superior educational performance, our data suggest that high educational performance may be a distinctive feature of bipolar disorder patients.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 2015 

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