Association between mild parkinsonian signs and mild cognitive impairment in a community.
BACKGROUND
Mild parkinsonian signs (MPS) are associated with prevalent and incident dementia but it is not known whether they are associated with mild cognitive impairment (MCI).


OBJECTIVE
To determine whether MPS and specific MPS (changes in axial function, rigidity, tremor) are associated with MCI in nondemented community-dwelling older people in northern Manhattan, NY.


METHODS
Participants underwent neurologic assessment, including a modified motor portion of the Unified Parkinson Disease Rating Scale. MCI was diagnosed in nondemented participants who had cognitive impairment based on neuropsychological testing and no functional impairment. Participants with MCI were classified as having MCI with memory impairment (MCI+M) vs MCI without memory impairment (MCI-M).


RESULTS
MCI was present in 608 (27.3%) of 2,230 participants, including 255 participants with MCI+M and 353 with MCI-M; 1,622 participants did not have MCI. MPS were present in 369 (16.5%) of 2,230 participants. In a univariate logistic regression model, odds of MCI+M (vs no MCI) were 51% higher in participants with MPS compared to those with no MPS (OR = 1.51, 95% CI = 1.09 to 2.09, p = 0.01). Multivariate models yielded similar results (OR = 1.45, 95% CI = 1.03 to 2.05, p = 0.03). Rigidity was present in a higher proportion of participants with MCI+M compared to participants without MCI.


CONCLUSIONS
Mild parkinsonian signs, especially rigidity, are associated with amnestic mild cognitive impairment. Mild parkinsonian signs and mild cognitive impairment may share similar pathogeneses. Whether this involves Alzheimer-type pathology, Lewy bodies, or vascular changes in the basal ganglia or basal ganglia circuitry deserves further investigation in postmortem studies.
Louis
E D
ED
The Gertrude H. Sergievsky Center, Taub Institute for Research on Alzheimer's Disease, New York, NY, USA. EDL2@columbia.edu
Schupf
N
N
Manly
J
J
Marder
K
K
Tang
M X
MX
Mayeux
R
R
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001479:Basal Ganglia / Q000473:pathology / Q000503:physiopathology; D001921:Brain / Q000503:physiopathology*; D015984:Causality; D002561:Cerebrovascular Disorders / Q000453:epidemiology / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D009127:Muscle Rigidity / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D009460:Neurologic Examination; D009483:Neuropsychological Tests; D020734:Parkinsonian Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology*; D011237:Predictive Value of Tests