title: Objective measurement of gait parameters in healthy and cognitively impaired elderly using the dual-task paradigm.
abstract: OBJECTIVE
  The present study explores the differences in gait parameters in elderly subjects with or without cognitive impairment measured by means of ambulatory actigraphy while performing a single and a dual task.
  
  
  METHODS
  Sixty-nine participants of which 23 individuals were diagnosed with Alzheimer's disease (AD), 24 individuals with mild cognitive impairment (MCI), and 22 healthy controls performed a single and dual walking task while wearing a wrist-worn accelerometer. Objective measures of gait features such as walking speed, cadence (i.e., number of steps per minute), and step variance (i.e., variance in time between two consecutive steps) were derived and analyzed.
  
  
  RESULTS
  While differences in several gait parameters, namely walking speed, were found between MCI and AD patients, no differences between healthy elderly and MCI patients were found.
  
  
  CONCLUSIONS
  Walking speed seems to be a gait-related feature that differs significantly between MCI and AD patients and thus could be used as an additional measurement in clinical assessment. However, differences in gait may not be salient enough in the early stages of dementia to be detected by actigraphy. More research comparing different methods to measure gait in early stages of dementia under different dual task conditions is neccessary.
authors.affiliation: CoBTeK Research Unit, University of Nice, Sophia Antipolis, France. a.konig@maastrichtuniversity.nl.|Centre Mémoire de Ressources et de Recherche, CHU de Nice, Nice, France. a.konig@maastrichtuniversity.nl.
authors.forename: Alexandra
authors.initials: A
authors.lastname: König
authors.affiliation: Philips Research, Eindhoven, The Netherlands.
authors.forename: Laura
authors.initials: L
authors.lastname: Klaming
authors.affiliation: Philips Research, Eindhoven, The Netherlands.
authors.forename: Marten
authors.initials: M
authors.lastname: Pijl
authors.affiliation: Centre Mémoire de Ressources et de Recherche, CHU de Nice, Nice, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Demeurraux
authors.affiliation: Centre Mémoire de Ressources et de Recherche, CHU de Nice, Nice, France.
authors.forename: Renaud
authors.initials: R
authors.lastname: David
authors.affiliation: CoBTeK Research Unit, University of Nice, Sophia Antipolis, France.|Centre Mémoire de Ressources et de Recherche, CHU de Nice, Nice, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Robert
mesh_terms: D061725:Accelerometry / Q000379:methods*; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology* / Q000523:psychology; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000503:physiopathology* / Q000523:psychology; D018450:Disease Progression; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D000073216:Mental Status and Dementia Tests; D000072797:Walking Speed / Q000502:physiology*
keywords: Accelerometer; Actigraphy; Alzheimer; Attention; Dementia; Dual-task; Gait; Mild cognitive impairment; Motor function