title: Diurnal variations in the outcomes of instrumented gait and quiet standing balance assessments and their association with falls history.
abstract: One in three adults aged over 65 falls every year, resulting in enormous costs to society. Incidents of falling vary with time of day, peaking in the early morning. The aim of this study was to determine if the ability of instrumented gait and balance assessments to discriminate between participants based on their falls history varies diurnally. Body-worn sensors were used during a 3 m gait assessment and a series of quiet standing balance tests. Each assessment was performed four times during a single day under supervised conditions in the participant's homes. 40 adults aged over 60 years (19 fallers) participated in this study. A range of parameters were derived for each assessment, and the ability of each parameter to discriminate between fallers and non-fallers at each recording time was examined. The effect of falls history on single support time varied significantly with recording time, with a significantly reduced single support time observed at the first and last recording session of the day. Differences were observed between fallers and non-fallers for a range of other gait parameters; however, these effects did not vary with assessment time. The quiet standing assessments examined in this study revealed significant variations with falls history; however, the sensitivity of the examined quiet standing assessments to falls risk does not appear to be time dependent. These results indicate that, with the exception of single support time, the association of gait and quiet standing balance parameters with falls risk does not vary diurnally.
authors.affiliation: Technology Research for Independent Living Centre, St. James's Hospital, Dublin, Ireland. emer.doheny@intel.com
authors.forename: Emer P
authors.initials: EP
authors.lastname: Doheny
authors.forename: Barry R
authors.initials: BR
authors.lastname: Greene
authors.forename: Timothy
authors.initials: T
authors.lastname: Foran
authors.forename: Clodagh
authors.initials: C
authors.lastname: Cunningham
authors.forename: Chie Wei
authors.initials: CW
authors.lastname: Fan
authors.forename: Rose Anne
authors.initials: RA
authors.lastname: Kenny
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data*; D000368:Aged; D000369:Aged, 80 and over; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D005684:Gait / Q000502:physiology*; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D004856:Postural Balance / Q000502:physiology*; D012307:Risk Factors