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Cognitive reserve lessens the burden of white matter lesions on executive functions in bipolar disorder

Published online by Cambridge University Press:  18 August 2016

S. Rolstad ,
C. Abé ,
E. Olsson ,
C. Eckerström  and
M. Landén
S. Rolstad*
Affiliation:
Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden
C. Abé
Affiliation:
Department of Clinical Neuroscience, Osher Center, Karolinska Institutet, Stockholm, Sweden
E. Olsson
Affiliation:
Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden
C. Eckerström
Affiliation:
Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden
M. Landén
Affiliation:
Institute of Neuroscience and Physiology, Sahlgrenska Academy at Gothenburg University, Gothenburg, Sweden Department of Clinical Neuroscience, Osher Center, Karolinska Institutet, Stockholm, Sweden Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
*
*Address for correspondence: S. Rolstad, Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Blå stråket 15, SE-413 45 Gothenburg, Sweden. (Email: sindre.rolstad@neuro.gu.se)
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Abstract

Background

The concept of cognitive reserve (CR) hypothesizes that intellectually stimulating activities provide resilience against brain pathology/disease. Whereas brain abnormalities and cognitive impairment are frequently reported in bipolar disorder (BD), it is unknown whether the impact of brain alterations can be lessened by higher CR in BD.

Method

We tested if higher CR would reduce the influence of total volumes of deep white matter hypointensities (WMH), ventricular cerebrospinal fluid (CSF), and prefrontal cortex on memory, executive, and attention/speed functions in patients with BD (n = 75). Linear regression models with interaction terms for CR and brain volumes were applied to directly test if CR reduces the influence of brain pathology on cognitive domains.

Results

CR reduced the influence of total volumes of deep WMH (β = −0.38, Q = 0.003) and ventricular CSF (β = −41, Q = 006) on executive functions.

Conclusions

The interactions between CR and total volumes of deep WMH/ventricular CSF appear to account for executive functioning in BD. The results suggest that the concept of CR is applicable in BD. Higher reserve capacity in BD alters the relationship between brain pathology and clinical presentation.

Keywords

Bipolar disordercognitioncognitive reservemagnetic resonance imaging
Type
Original Articles
Information
Psychological Medicine , Volume 46 , Issue 15 , November 2016 , pp. 3095 - 3104
Copyright
Copyright © Cambridge University Press 2016 

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