This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on ISI (15)  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Dementias  • Movement Disorders  • Parkinson Disease/ Parkinsonian Disorders  • Aging/ Geriatrics  • Alert me on articles by topic

Risk of Incident Dementia

Elan D. Louis, MD, MS; Ming X. Tang, PhD; Richard Mayeux, MD, MSc

Arch Neurol. 2004;61:1273-1276.

Background  Mild parkinsonian signs occur in 30% to 40% of community-dwelling older people. In a cross-sectional study, the severity of these signs was greater in people with dementia than in people without dementia.

Objective  To determine whether baseline mild parkinsonian signs are a predictor of incident dementia.

Design  A prospective, longitudinal study of community-dwelling older people who did not have dementia or Parkinson disease at baseline.

Methods  A neurological examination was performed on 1028 residents aged 65 years or older in the Washington Height–Inwood community in northern Manhattan, NY. Parkinsonian signs were rated with an abbreviated Unified Parkinson’s Disease Rating Scale, resulting in a parkinsonian sign score (range, 0-40). The risk of incident dementia was assessed using Cox proportional hazards models. In some analyses, data from the modified Unified Parkinson’s Disease Rating Scale were divided into 3 domains: rigidity, axial function, and tremor at rest.

Results  The mean duration of follow-up was 5.6 years, and 224 participants (21.8%) developed dementia. In a Cox model, the risk of incident dementia was 57% higher in participants with a baseline parkinsonian sign score of 2 vs 0 (relative risk, 1.56; 95% confidence interval, 1.04-2.33; P = .03). In a second Cox model, the baseline parkinsonian sign score was associated with incident dementia (relative risk, 1.08; 95% confidence interval, 1.01-1.16; P = .02) independent of associations with baseline age, education, ethnicity, diabetes mellitus, and stroke.

Conclusions  Baseline mild parkinsonian signs are a predictor of incident dementia. Although these signs are mild, they are not prognostically benign. Brain imaging and postmortem examinations might further our insight into the anatomical and pathological basis for mild parkinsonian signs.

Author Affiliations: The Gertrude H. Sergievsky Center (Drs Louis, Tang, and Mayeux), Department of Neurology (Drs Louis and Mayeux), Taub Institute for Research on Alzheimer’s Disease and the Aging Brain (Drs Louis and Mayeux), Department of Biostatistics (Drs Tang and Mayeux), Department of Psychiatry (Dr Mayeux), College of Physicians and Surgeons, Columbia University, New York, NY.

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Mild Parkinsonian Signs and Plasma Homocysteine Concentration in Community-Dwelling Elderly Individuals
Louis et al.
Arch Neurol 2007;64:1646-1651.
ABSTRACT | FULL TEXT  

History of vascular disease and mild parkinsonian signs in community-dwelling elderly individuals.
Louis and Luchsinger
Arch Neurol 2006;63:717-722.
ABSTRACT | FULL TEXT  

Parkinsonian signs in subjects with mild cognitive impairment
Boyle et al.
Neurology 2005;65:1901-1906.
ABSTRACT | FULL TEXT  

Association between mild parkinsonian signs and mild cognitive impairment in a community
Louis et al.
Neurology 2005;64:1157-1161.
ABSTRACT | FULL TEXT