title: Verbal memory declines more in female patients with Parkinson's disease: the importance of gender-corrected normative data.
abstract: 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.
  
  
  
  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.
  
  
  
  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.
  
  
  
  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.
authors.affiliation: Department of Medical Psychology,University Hospital Cologne,Germany.
authors.forename: S
authors.initials: S
authors.lastname: Fengler
authors.affiliation: Department of Neurology,University Hospital Bonn, and German Center for Neurodegenerative Diseases (DZNE),Bonn,Germany.
authors.forename: S
authors.initials: S
authors.lastname: Roeske
authors.affiliation: Department of Neurology,Medical Faculty,RWTH Aachen University,Germany.
authors.forename: I
authors.initials: I
authors.lastname: Heber
authors.affiliation: Department of Neurology,Medical Faculty,RWTH Aachen University,Germany.
authors.forename: K
authors.initials: K
authors.lastname: Reetz
authors.affiliation: Department of Neurology,Medical Faculty,RWTH Aachen University,Germany.
authors.forename: J B
authors.initials: JB
authors.lastname: Schulz
authors.affiliation: Leibniz-Institute of Prevention Research and Epidemiology,Department of Clinical Epidemiology,Bremen,Germany.
authors.forename: O
authors.initials: O
authors.lastname: Riedel
authors.affiliation: Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden,Germany.
authors.forename: H U
authors.initials: HU
authors.lastname: Wittchen
authors.affiliation: Division of Neurodegenerative Diseases,Department of Neurology,Technische Universität Dresden,Germany.
authors.forename: A
authors.initials: A
authors.lastname: Storch
authors.affiliation: Division of Neurodegenerative Diseases,Department of Neurology,Technische Universität Dresden,Germany.
authors.forename: K
authors.initials: K
authors.lastname: Linse
authors.affiliation: Department of Neurology,J.W. Goethe University,Frankfurt/Main,Germany.
authors.forename: S
authors.initials: S
authors.lastname: Baudrexel
authors.affiliation: Department of Neurology,J.W. Goethe University,Frankfurt/Main,Germany.
authors.forename: R
authors.initials: R
authors.lastname: Hilker
authors.affiliation: Department of Neuropathology,University Medical Center Goettingen,Germany.
authors.forename: B
authors.initials: B
authors.lastname: Mollenhauer
authors.affiliation: Department of Neurology,Christian Albrechts University,Kiel,Germany.
authors.forename: K
authors.initials: K
authors.lastname: Witt
authors.affiliation: Department of Neurology,Christian Albrechts University,Kiel,Germany.
authors.forename: N
authors.initials: N
authors.lastname: Schmidt
authors.affiliation: Department of Neurology,Philipps University Marburg,Germany.
authors.forename: M
authors.initials: M
authors.lastname: Balzer-Geldsetzer
authors.affiliation: Department of Neurology,Philipps University Marburg,Germany.
authors.forename: J
authors.initials: J
authors.lastname: Dams
authors.affiliation: Department of Neurology,Philipps University Marburg,Germany.
authors.forename: R
authors.initials: R
authors.lastname: Dodel
authors.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.
authors.forename: S
authors.initials: S
authors.lastname: Gräber
authors.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.
authors.forename: A
authors.initials: A
authors.lastname: Pilotto
authors.affiliation: Institute of Gerontology & Center for Neuropsychological Diagnostics and Intervention (CeNDI), University of Vechta,Germany.
authors.forename: A
authors.initials: A
authors.lastname: Petrelli
authors.affiliation: Department of Neurology,University of Ulm,Germany.
authors.forename: S
authors.initials: S
authors.lastname: Fünkele
authors.affiliation: Department of Neurology,University of Ulm,Germany.
authors.forename: J
authors.initials: J
authors.lastname: Kassubek
authors.affiliation: Department of Medical Psychology,University Hospital Cologne,Germany.
authors.forename: E
authors.initials: E
authors.lastname: Kalbe
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D060825:Cognitive Dysfunction / Q000209:etiology / Q000503:physiopathology*; D003704:Dementia / Q000209:etiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000503:physiopathology*; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications / Q000503:physiopathology*; D012737:Sex Factors; D014706:Verbal Learning / Q000502:physiology*
keywords: Cognition; Parkinson's disease; gender