title: Heterogeneity of brain glucose metabolism in mild cognitive impairment and clinical progression to Alzheimer disease.
abstract: BACKGROUND
  Subjects with amnesic mild cognitive impairment (aMCI) may include patients at high risk for progression to Alzheimer disease (AD) and a population with different underlying pathologic conditions.
  
  
  OBJECTIVE
  To evaluate the potential roles of positron emission tomography with fluorodeoxyglucose F 18 (18FDG-PET) and memory scores in identifying subjects with aMCI and in predicting progression to dementia.
  
  
  METHODS
  Sixty-seven patients at European centers for neurologic and AD care who were diagnosed as having aMCI each underwent an extensive clinical and neuropsychological examination and an 18FDG-PET study. Forty-eight subjects were followed up periodically for at least 1 year, and progression to dementia was evaluated.
  
  
  METHODS
  Brain glucose metabolism and memory scores.
  
  
  RESULTS
  Fourteen subjects with aMCI who converted to AD within 1 year showed bilateral hypometabolism in the inferior parietal, posterior cingulate, and medial temporal cortex. Subjects with "stable" aMCI presented with hypometabolism in the dorsolateral frontal cortex. The severity of memory impairment, as evaluated by the California Verbal Learning Test-Long Delay Free Recall scores, correlated with the following brain metabolic patterns: scores less than 7 were associated with a typical 18FDG-PET AD pattern, and scores of 7 or higher were associated with hypometabolism in the dorsolateral frontal cortex and no progression to AD.
  
  
  CONCLUSIONS
  These data provide evidence for clinical and functional heterogeneity among subjects with aMCI and suggest that 18FDG-PET findings combined with memory scores may be useful in predicting short-term conversion to AD.
authors.affiliation: Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele, Milan, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Anchisi
authors.forename: Barbara
authors.initials: B
authors.lastname: Borroni
authors.forename: Massimo
authors.initials: M
authors.lastname: Franceschi
authors.forename: Nasser
authors.initials: N
authors.lastname: Kerrouche
authors.forename: Elke
authors.initials: E
authors.lastname: Kalbe
authors.forename: Bettina
authors.initials: B
authors.lastname: Beuthien-Beumann
authors.forename: Stephano
authors.initials: S
authors.lastname: Cappa
authors.forename: Olaf
authors.initials: O
authors.lastname: Lenz
authors.forename: Stephan
authors.initials: S
authors.lastname: Ludecke
authors.forename: Alessandra
authors.initials: A
authors.lastname: Marcone
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Mielke
authors.forename: Paola
authors.initials: P
authors.lastname: Ortelli
authors.forename: Alessandro
authors.initials: A
authors.lastname: Padovani
authors.forename: Oriana
authors.initials: O
authors.lastname: Pelati
authors.forename: Alberto
authors.initials: A
authors.lastname: Pupi
authors.forename: Elio
authors.initials: E
authors.lastname: Scarpini
authors.forename: Simon
authors.initials: S
authors.lastname: Weisenbach
authors.forename: Karl
authors.initials: K
authors.lastname: Herholz
authors.forename: Erik
authors.initials: E
authors.lastname: Salmon
authors.forename: Vjera
authors.initials: V
authors.lastname: Holthoff
authors.forename: Sandro
authors.initials: S
authors.lastname: Sorbi
authors.forename: Ferruccio
authors.initials: F
authors.lastname: Fazio
authors.forename: Daniela
authors.initials: D
authors.lastname: Perani
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000209:etiology* / Q000378:metabolism; D001931:Brain Mapping; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000378:metabolism*; D003710:Demography; D018450:Disease Progression; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D005500:Follow-Up Studies; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods; D011581:Psychological Tests / Q000706:statistics & numerical data; D012372:ROC Curve
chemical_list: D019788:Fluorodeoxyglucose F18; D005947:Glucose