Parkinson disease with dementia: comparing patients with and without Alzheimer pathology.
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.
Sabbagh
Marwan N
MN
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
Adler
Charles H
CH
Lahti
Tyson J
TJ
Connor
Donald J
DJ
Vedders
Linda
L
Peterson
Lars K
LK
Caviness
John N
JN
Shill
Holly A
HA
Sue
Lucia I
LI
Ziabreva
Iryna
I
Perry
Elaine
E
Ballard
Clive G
CG
Aarsland
Dag
D
Walker
Douglas G
DG
Beach
Thomas G
TG
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*