title: Cortical cholinergic function is more severely affected in parkinsonian dementia than in Alzheimer disease: an in vivo positron emission tomographic study.
abstract: BACKGROUND
  Pathology reports have shown that cholinergic forebrain neuronal losses in parkinsonian dementia (PDem) are equal to or greater than those in Alzheimer disease (AD). We hypothesized that patients with PDem would have cholinergic deficits that were similar to or greater than those of patients with AD.
  
  
  OBJECTIVE
  To determine in vivo cortical acetylcholinesterase (AChE) activity in healthy control subjects and in patients with mild AD, PDem, and Parkinson disease without dementia using AChE positron emission tomography.
  
  
  METHODS
  University and Veterans' Administration medical center. Design and Patients Group comparison design of patients with AD (n = 12), PDem (n = 14), and Parkinson disease without dementia (n = 11), and controls (n = 10) who underwent AChE imaging between July 1, 2000, and January 31, 2003. Patients with AD and PDem had approximately equal dementia severity.
  
  
  METHODS
  Cerebral AChE activity.
  
  
  RESULTS
  Compared with controls, mean cortical AChE activity was lowest in patients with PDem (-20.0%), followed by patients with Parkinson disease without dementia (-12.9%; P<.001). Mean cortical AChE activity was relatively preserved in patients with AD (-9.1%), except for regionally selective involvement of the lateral temporal cortex (-15%; P<.001).
  
  
  CONCLUSIONS
  Reduced cortical AChE activity is more characteristic of patients with PDem than of patients with mild AD.
authors.affiliation: Departments of Neurology and Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
authors.forename: Nicolaas I
authors.initials: NI
authors.lastname: Bohnen
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Kaufer
authors.forename: Larry S
authors.initials: LS
authors.lastname: Ivanco
authors.forename: Brian
authors.initials: B
authors.lastname: Lopresti
authors.forename: Robert A
authors.initials: RA
authors.lastname: Koeppe
authors.forename: James G
authors.initials: JG
authors.lastname: Davis
authors.forename: Chester A
authors.initials: CA
authors.lastname: Mathis
authors.forename: Robert Y
authors.initials: RY
authors.lastname: Moore
authors.forename: Steven T
authors.initials: ST
authors.lastname: DeKosky
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000368:Aged; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000201:enzymology*; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000201:enzymology*; D003704:Dementia / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D010300:Parkinson Disease / Q000150:complications* / Q000000981:diagnostic imaging / Q000201:enzymology*; D014055:Tomography, Emission-Computed
chemical_list: D000110:Acetylcholinesterase