title: One walk a year to 1000 within a year: continuous in-home unobtrusive gait assessment of older adults.
abstract: Physical performance measures predict health and function in older populations. Walking speed in particular has consistently predicted morbidity and mortality. However, single brief walking measures may not reflect a person's typical ability. Using a system that unobtrusively and continuously measures walking activity in a person's home we examined walking speed metrics and their relation to function. In 76 persons living independently (mean age, 86) we measured every instance of walking past a line of passive infra-red motion sensors placed strategically in their home during a four-week period surrounding their annual clinical evaluation. Walking speeds and the variance in these measures were calculated and compared to conventional measures of gait, motor function and cognition. Median number of walks per day was 18±15. Overall mean walking speed was 61±17 cm/s. Characteristic fast walking speed was 96 cm/s. Men walked as frequently and fast as women. Those using a walking aid walked significantly slower and with greater variability. Morning speeds were significantly faster than afternoon/evening speeds. In-home walking speeds were significantly associated with several neuropsychological tests as well as tests of motor performance. Unobtrusive home walking assessments are ecologically valid measures of walking function. They provide previously unattainable metrics (periodicity, variability, range of minimum and maximum speeds) of everyday motor function.
authors: Oregon Center for Aging & Technology, Oregon Health & Science University, Portland, OR 97239-3098, USA. kaye@ohsu.edu
authors: Jeffrey
authors: J
authors: Kaye
authors: Nora
authors: N
authors: Mattek
authors: Hiroko
authors: H
authors: Dodge
authors: Teresa
authors: T
authors: Buracchio
authors: Daniel
authors: D
authors: Austin
authors: Stuart
authors: S
authors: Hagler
authors: Michael
authors: M
authors: Pavel
authors: Tamara
authors: T
authors: Hayes
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002940:Circadian Rhythm; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005684:Gait / Q000502:physiology*; D015577:Geriatric Assessment; D006801:Humans; D057187:Independent Living; D016014:Linear Models; D008297:Male; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods*; D010807:Physical Endurance / Q000502:physiology*; D004856:Postural Balance / Q000502:physiology; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012737:Sex Factors; D012815:Signal Processing, Computer-Assisted; D016138:Walking / Q000502:physiology*