title: Quantitative gait dysfunction and risk of cognitive decline and dementia.
abstract: BACKGROUND
  Identifying quantitative gait markers of preclinical dementia may lead to new insights into early disease stages, improve diagnostic assessments and identify new preventive strategies.
  
  
  OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  Our findings indicate that quantitative gait measures predict future risk of cognitive decline and dementia in initially non-demented older adults.
authors.affiliation: Department of Neurology, Albert Einstein College of Medicine, 1165 Morris Park Avenue, Room 338, Bronx, New York 10461, USA. jverghes@aecom.yu.edu
authors.forename: Joe
authors.initials: J
authors.lastname: Verghese
authors.forename: Cuiling
authors.initials: C
authors.lastname: Wang
authors.forename: Richard B
authors.initials: RB
authors.lastname: Lipton
authors.forename: Roee
authors.initials: R
authors.lastname: Holtzer
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Xue
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000453:epidemiology*; D015331:Cohort Studies; D003704:Dementia / Q000453:epidemiology*; D005260:Female; D020233:Gait Disorders, Neurologic / Q000523:psychology*; D006801:Humans; D015994:Incidence; D008297:Male; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D012720:Severity of Illness Index