title: Mild cognitive impairment in drug-naive patients with PD is associated with cerebral hypometabolism.
abstract: OBJECTIVE
  To characterize brain metabolic changes associated with mild cognitive impairment (MCI) in drug-naive patients with Parkinson disease (PD) using (18)F-fluorodeoxyglucose (FDG) and PET (FDG-PET).
  
  
  METHODS
  This cross-sectional study included newly diagnosed patients with PD with MCI in single or multiple domain (PD-MCI; n =12) and without MCI (PD-nMCI; n =12), and healthy controls (n =12). The groups were matched for age. Moreover, the patient groups were matched for motor disability. All subjects underwent a FDG-PET study. Cerebral regional relative metabolic maps were compared in PD-MCI, PD-nMCI, and controls using regions of interest analysis (ROIs) and voxel-based analysis with statistical parametric mapping.
  
  
  RESULTS
  ROIs and voxel-based analyses revealed significant relative hypometabolism in the prefrontal, superior/inferior parietal, and associative occipital cortices as well as in the striatum in patients with PD-MCI relative to controls (p < 0.05) and to a lesser extent in patients with PD-nMCI. In contrast, patients with PD-nMCI did not show significant metabolic changes as compared to controls.
  
  
  CONCLUSIONS
  MCI in patients with PD is associated with cortical hypometabolism since the earliest stage, independent of therapy or motor disability. The early involvement of posterior cortical region, a pattern shared by advanced stages of PD-MCI and PD with dementia, could represent an early marker of dementia. The relevance of this pattern in predicting prodromal dementia has to be evaluated in longitudinal studies.
authors.affiliation: Institute of Biostructure and Bioimaging, CNR, Naples, Italy. sabina.pappata@cnr.it
authors.forename: Sabina
authors.initials: S
authors.lastname: Pappatà
authors.forename: G
authors.initials: G
authors.lastname: Santangelo
authors.forename: D
authors.initials: D
authors.lastname: Aarsland
authors.forename: C
authors.initials: C
authors.lastname: Vicidomini
authors.forename: K
authors.initials: K
authors.lastname: Longo
authors.forename: K
authors.initials: K
authors.lastname: Bronnick
authors.forename: M
authors.initials: M
authors.lastname: Amboni
authors.forename: R
authors.initials: R
authors.lastname: Erro
authors.forename: C
authors.initials: C
authors.lastname: Vitale
authors.forename: M G
authors.initials: MG
authors.lastname: Caprio
authors.forename: M T
authors.initials: MT
authors.lastname: Pellecchia
authors.forename: A
authors.initials: A
authors.lastname: Brunetti
authors.forename: G
authors.initials: G
authors.lastname: De Michele
authors.forename: M
authors.initials: M
authors.lastname: Salvatore
authors.forename: P
authors.initials: P
authors.lastname: Barone
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001931:Brain Mapping; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000378:metabolism*; D016009:Chi-Square Distribution; D003072:Cognition Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000378:metabolism*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications*; D049268:Positron-Emission Tomography
chemical_list: D019788:Fluorodeoxyglucose F18