title: Parkinson disease with dementia: comparing patients with and without Alzheimer pathology.
abstract: Subjects with Parkinson disease (PD) frequently develop dementia with greater than one-third meeting neuropathologic diagnostic criteria for Alzheimer disease (AD). The objective is to identify clinical and neuropathologic differences between Parkinson disease with dementia (PDD) subjects, with and without coexistent AD pathology. Neuropathologic examination was available on subjects diagnosed by clinicopathologic criteria with PDD-AD (N=23) and PDD+AD (N=28). A small subset of subjects with PDD-AD and PDD+AD had received at least 1 standardized neuropsychologic assessment. PDD+AD subjects were significantly older at age of PD onset and death, progressed to onset of dementia in less time, and had a shorter duration of PD symptoms before the onset of dementia. Education, responsiveness of L-dopa and dopaminergic medications, presence of cognitive fluctuations and hallucinations, and mean Mini-Mental State Examination, Global Deterioration Scale, Functional Assessment Staging, and Unified Parkinson Disease Rating Scale scores did not differ significantly between the 2 groups. The PDD+AD group had significantly greater total plaques, neuritic plaques, total tangles, and Braak stages compared with PDD-AD. This study suggests that it is difficult to distinguish PDD+AD and PDD-AD on the basis of movement, clinical, and neuropsychologic assessment. PDD-AD and PDD+AD have similar degrees of dementia and approximately half of PDD subjects have enough AD pathology to attain a neuropathologic diagnosis of AD. PDD can develop in the absence of significant Alzheimer pathology.
authors.affiliation: The Cleo Roberts Center for Clinical Research, Harold Civin Laboratory of Neuropathology, Sun Health Research Institute, 10515 West Santa Fe Drive, Sun City, AZ 85351, USA. marwan.sabbagh@sunhealth.org
authors.forename: Marwan N
authors.initials: MN
authors.lastname: Sabbagh
authors.forename: Charles H
authors.initials: CH
authors.lastname: Adler
authors.forename: Tyson J
authors.initials: TJ
authors.lastname: Lahti
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Connor
authors.forename: Linda
authors.initials: L
authors.lastname: Vedders
authors.forename: Lars K
authors.initials: LK
authors.lastname: Peterson
authors.forename: John N
authors.initials: JN
authors.lastname: Caviness
authors.forename: Holly A
authors.initials: HA
authors.lastname: Shill
authors.forename: Lucia I
authors.initials: LI
authors.lastname: Sue
authors.forename: Iryna
authors.initials: I
authors.lastname: Ziabreva
authors.forename: Elaine
authors.initials: E
authors.lastname: Perry
authors.forename: Clive G
authors.initials: CG
authors.lastname: Ballard
authors.forename: Dag
authors.initials: D
authors.lastname: Aarsland
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Walker
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Beach
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications / Q000473:pathology*; D003704:Dementia / Q000150:complications / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000150:complications / Q000473:pathology*