Quantitative gait dysfunction and risk of cognitive decline and dementia

Department of Neurology, Albert Einstein College of Medicine, 1165 Morris Park Avenue, Room 338, Bronx, New York 10461, USA.
Journal of neurology, neurosurgery, and psychiatry (Impact Factor: 5.58). 10/2007; 78(9):929-35. DOI: 10.1136/jnnp.2006.106914
Source: PubMed

ABSTRACT Identifying quantitative gait markers of preclinical dementia may lead to new insights into early disease stages, improve diagnostic assessments and identify new preventive strategies.
To examine the relationship of quantitative gait parameters to decline in specific cognitive domains as well as the risk of developing dementia in older adults.
We conducted a prospective cohort study nested within a community based ageing study. Of the 427 subjects aged 70 years and older with quantitative gait assessments, 399 were dementia-free at baseline.
Over 5 years of follow-up (median 2 years), 33 subjects developed dementia. Factor analysis was used to reduce eight baseline quantitative gait parameters to three independent factors representing pace, rhythm and variability. In linear models, a 1 point increase on the rhythm factor was associated with further memory decline (by 107%), whereas the pace factor was associated with decline on executive function measured by the digit symbol substitution (by 29%) and letter fluency (by 92%) tests. In Cox models adjusted for age, sex and education, a 1 point increase on baseline rhythm (hazard ratio (HR) 1.48; 95% CI 1.03 to 2.14) and variability factor scores (HR 1.37; 95% CI 1.05 to 1.78) was associated with increased risk of dementia. The pace factor predicted the risk of developing vascular dementia (HR 1.60; 95% CI 1.06 to 2.41).
Our findings indicate that quantitative gait measures predict future risk of cognitive decline and dementia in initially non-demented older adults.

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Available from: Richard Lipton, Jun 26, 2015
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