title: Extrapyramidal features in Parkinson's disease with and without dementia and dementia with Lewy bodies: A cross-sectional comparative study.
abstract: Risk factors predicting an increased risk of dementia in Parkinson's disease (PD) are not fully established. The dementia associated with PD (PDD) closely resembles dementia with Lewy bodies (DLB). Based upon a high frequency of non-dopaminergic mediated clinical features in DLB, we predicted that a motor subtype comprising postural instability and balance problems would be more common in PDD. We examined extrapyramidal, cognitive, and affective features in 38 PD, 43 PDD, and 26 DLB patients in a cross-sectional study design. Motor subtype was subdivided into postural-instability gait difficulty (PIGD) or tremor (TD) dominant. The PIGD-subtype was more common in PDD (88% of cases) and DLB (69% of cases) groups compared with the PD group (38% of cases), in which TD and PIGD sub-types were more equally represented (P < 0.001). Although the mean depression scores overall were modest, PDD patients scored significantly higher than PD, but not DLB patients (Cornell; P = 0.006, and Geriatric Depression scale, GDS-15; P = 0.001), while within the PD group, those patients with a PIGD subtype had greater depression scores than the TD subtype (GDS-15; P < 0.05). We conclude that non-dopaminergic motor features are frequent in PDD. Neurodegeneration within the cholinergic system is likely to mediate many of these motor problems, as well as playing a significant role in determining the neuropsychiatric symptomatology of both PDD and DLB.
authors.affiliation: Department of Neurology, Regional Neurosciences Centre, Newcastle General Hospital, Newcastle upon Tyne, United Kingdom.
authors.forename: David J
authors.initials: DJ
authors.lastname: Burn
authors.forename: Elise N
authors.initials: EN
authors.lastname: Rowan
authors.forename: Thais
authors.initials: T
authors.lastname: Minett
authors.forename: Jonathon
authors.initials: J
authors.lastname: Sanders
authors.forename: Pat
authors.initials: P
authors.lastname: Myint
authors.forename: Jonathon
authors.initials: J
authors.lastname: Richardson
authors.forename: Alan
authors.initials: A
authors.lastname: Thomas
authors.forename: Jane
authors.initials: J
authors.lastname: Newby
authors.forename: Jenny
authors.initials: J
authors.lastname: Reid
authors.forename: John T
authors.initials: JT
authors.lastname: O'Brien
authors.forename: Ian G
authors.initials: IG
authors.lastname: McKeith
mesh_terms: D000368:Aged; D001480:Basal Ganglia Diseases / Q000453:epidemiology*; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003704:Dementia / Q000453:epidemiology; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000453:epidemiology*; D008297:Male; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000453:epidemiology* / Q000503:physiopathology*; D010641:Phenotype; D012307:Risk Factors; D012720:Severity of Illness Index