title: Initial cognitive decline is associated with cortical thinning in early Parkinson disease.
abstract: OBJECTIVE
  Our aim was to assess cortical thickness in a large multicenter cohort of drug-naive patients with early Parkinson disease (PD), with and without mild cognitive impairment (MCI), and explore the cognitive correlates of regional cortical thinning.
  
  
  METHODS
  One hundred twenty-three newly diagnosed patients with PD and 56 healthy controls with 3-tesla structural MRI scans and complete neuropsychological assessment from the Parkinson's Progression Markers Initiative were included. Modified Movement Disorders Society Task Force level II criteria were applied to diagnose MCI in PD. FreeSurfer image processing and analysis software was used to measure cortical thickness across groups and the association with cognitive domains and tests.
  
  
  RESULTS
  In patients with MCI, atrophy was found in temporal, parietal, frontal, and occipital areas compared with controls. Specific regional thinning in the right inferior temporal cortex was also found in cognitively normal patients. Memory, executive, and visuospatial performance was associated with temporoparietal and superior frontal thinning, suggesting a relationship between cognitive impairment and both anterior and posterior cortical atrophy in the whole patient sample.
  
  
  CONCLUSIONS
  These findings confirm that MCI is associated with widespread cortical atrophy. In addition, they suggest that regional cortical thinning is already present at the time of diagnosis in patients with early, untreated PD who do not meet the criteria for MCI. Together, the results indicate that cortical thinning can serve as a marker for initial cognitive decline in early PD.
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway. joana.pereira@ki.se.
authors.forename: Joana B
authors.initials: JB
authors.lastname: Pereira
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Per
authors.initials: P
authors.lastname: Svenningsson
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Daniel
authors.initials: D
authors.lastname: Weintraub
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Kolbjørn
authors.initials: K
authors.lastname: Brønnick
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Alexander
authors.initials: A
authors.lastname: Lebedev
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Eric
authors.initials: E
authors.lastname: Westman
authors.affiliation: From the Department of Neurobiology, Care Sciences and Society (J.B.P., E.W.), and Centre for Alzheimer's Disease Research, Department of Neurobiology, Care Sciences and Society (D.A.), Karolinska Institutet, Stockholm; Centre for Molecular Medicine (P.S.), Department of Neurology and Clinical Neuroscience, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden; Department of Psychiatry and Neurology (D.W.), Perelman School of Medicine at the University of Pennsylvania, Philadelphia VA Medical Center; and The Norwegian Center for Movement Disorders (K.B.), and Centre for Age-Related Medicine, Department of Psychiatry (A.L., D.A.), Stavanger University Hospital, Stavanger, Norway.
authors.forename: Dag
authors.initials: D
authors.lastname: Aarsland
mesh_terms: D000368:Aged; D001284:Atrophy; D015415:Biomarkers; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D015577:Geriatric Assessment; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000145:classification / Q000473:pathology* / Q000503:physiopathology
chemical_list: D015415:Biomarkers