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Verbal memory declines more in female patients with Parkinson's disease: the importance of gender-corrected normative data

Published online by Cambridge University Press:  19 May 2016

S. Fengler ,
S. Roeske ,
I. Heber ,
K. Reetz ,
J. B. Schulz ,
O. Riedel ,
H.U. Wittchen ,
A. Storch ,
K. Linse  and
S. Baudrexel
...Show all authors
S. Fengler
Affiliation:
Department of Medical Psychology, University Hospital Cologne, Germany Institute of Gerontology & Center for Neuropsychological Diagnostics and Intervention (CeNDI), University of Vechta, Germany
S. Roeske
Affiliation:
Department of Neurology, University Hospital Bonn, and German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
I. Heber
Affiliation:
Department of Neurology, Medical Faculty, RWTH Aachen University, Germany
K. Reetz
Affiliation:
Department of Neurology, Medical Faculty, RWTH Aachen University, Germany JARA – Translational Brain Medicine, Jülich and Aachen, Germany
J. B. Schulz
Affiliation:
Department of Neurology, Medical Faculty, RWTH Aachen University, Germany JARA – Translational Brain Medicine, Jülich and Aachen, Germany
O. Riedel
Affiliation:
Leibniz-Institute of Prevention Research and Epidemiology, Department of Clinical Epidemiology, Bremen, Germany
H.U. Wittchen
Affiliation:
Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Germany
A. Storch
Affiliation:
Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Germany
K. Linse
Affiliation:
Division of Neurodegenerative Diseases, Department of Neurology, Technische Universität Dresden, Germany
S. Baudrexel
Affiliation:
Department of Neurology, J.W. Goethe University, Frankfurt/Main, Germany
R. Hilker
Affiliation:
Department of Neurology, J.W. Goethe University, Frankfurt/Main, Germany
B. Mollenhauer
Affiliation:
Department of Neuropathology, University Medical Center Goettingen, Germany Paracelsus-Elena Clinic, Centre of Parkinsonism and Movement Disorders, Kassel, Germany
K. Witt
Affiliation:
Department of Neurology, Christian Albrechts University, Kiel, Germany
N. Schmidt
Affiliation:
Department of Neurology, Christian Albrechts University, Kiel, Germany
M. Balzer-Geldsetzer
Affiliation:
Department of Neurology, Philipps University Marburg, Germany
J. Dams
Affiliation:
Department of Neurology, Philipps University Marburg, Germany
R. Dodel
Affiliation:
Department of Neurology, Philipps University Marburg, Germany
S. Gräber
Affiliation:
Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research and German Center for Neurodegenerative Diseases (DZNE), University Tübingen, and German Center for Neurodegenerative Diseases, Tübingen, Germany
A. Pilotto
Affiliation:
Department of Neurodegenerative Diseases, Hertie Institute for Clinical Brain Research and German Center for Neurodegenerative Diseases (DZNE), University Tübingen, and German Center for Neurodegenerative Diseases, Tübingen, Germany
A. Petrelli
Affiliation:
Institute of Gerontology & Center for Neuropsychological Diagnostics and Intervention (CeNDI), University of Vechta, Germany
S. Fünkele
Affiliation:
Department of Neurology, University of Ulm, Germany
J. Kassubek
Affiliation:
Department of Neurology, University of Ulm, Germany
E. Kalbe*
Affiliation:
Department of Medical Psychology, University Hospital Cologne, Germany Institute of Gerontology & Center for Neuropsychological Diagnostics and Intervention (CeNDI), University of Vechta, Germany
*
*Address for correspondence: Prof. Dr. E. Kalbe, Department of Medical Psychology, University Hospital Cologne, Kerpener Str. 68, 50937 Cologne, Germany. (Email: [email protected])
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Abstract

Background

Data on gender-specific profiles of cognitive functions in patients with Parkinson's disease (PD) are rare and inconsistent, and possible disease-confounding factors have been insufficiently considered.

Method

The LANDSCAPE study on cognition in PD enrolled 656 PD patients (267 without cognitive impairment, 66% male; 292 with mild cognitive impairment, 69% male; 97 with PD dementia, 69% male). Raw values and age-, education-, and gender-corrected Z scores of a neuropsychological test battery (CERAD-Plus) were compared between genders. Motor symptoms, disease duration, l-dopa equivalent daily dose, depression - and additionally age and education for the raw value analysis - were taken as covariates.

Results

Raw-score analysis replicated results of previous studies in that female PD patients were superior in verbal memory (word list learning, p = 0.02; recall, p = 0.03), while men outperformed women in visuoconstruction (p = 0.002) and figural memory (p = 0.005). In contrast, gender-corrected Z scores showed that men were superior in verbal memory (word list learning, p = 0.02; recall, p = 0.02; recognition, p = 0.04), while no difference was found for visuospatial tests. This picture could be observed both in the overall analysis of PD patients as well as in a differentiated group analysis.

Conclusions

Normative data corrected for gender and other sociodemographic variables are relevant, since they may elucidate a markedly different cognitive profile compared to raw scores. Our study also suggests that verbal memory decline is stronger in women than in men with PD. Future studies are needed to replicate these findings, examine the progression of gender-specific cognitive decline in PD and define different underlying mechanisms of this dysfunction.

Keywords

CognitiongenderParkinson's disease
Type
Original Articles
Information
Psychological Medicine , Volume 46 , Issue 11 , August 2016 , pp. 2275 - 2286
Copyright
Copyright © Cambridge University Press 2016 

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