title: Motor Performance and Physical Activity as Predictors of Prospective Falls in Community-Dwelling Older Adults by Frailty Level: Application of Wearable Technology.
abstract: Few studies of the association between prospective falls and sensor-based measures of motor performance and physical activity (PA) have evaluated subgroups of frailty status separately.
  
  
  
  To evaluate wearable sensor-based measures of gait, balance, and PA that are predictive of future falls in community-dwelling older adults.
  
  
  
  The Arizona Frailty Cohort Study in Tucson, Arizona, followed community-dwelling adults aged 65 years and over (without baseline cognitive deficit, severe movement disorders, or recent stroke) for falls over 6 months. Baseline measures included Fried frailty criteria: in-home and sensor-based gait (normal and fast walk), balance (bipedal eyes open and eyes closed), and spontaneous daily PA over 48 h, measured using validated wearable technologies.
  
  
  
  Of the 119 participants (36% non-frail, 48% pre-frail, and 16% frail), 48 reported one or more fall (47% of non-frail, 33% of pre-frail, and 47% of frail). Although balance deficit and PA were independent fall predictors in pre-frail and frail groups, they were not sensitive to predict prospective falls in the non-frail group. Even though gait performance deteriorated as frailty increased, gait was not a predictor of prospective falls when participants were stratified based on frailty status. In pre-frail and frail participants combined, center of mass sway [odds ratio (OR) = 5.9, 95% confidence interval (CI) 2.6-13.7], PA mean walking bout duration (OR = 1.1, 95% CI 1.0-1.2), PA mean standing bout duration (OR = 0.94, 95% CI 0.91-0.99), and a fall in previous 6 months (OR = 7.3, 95% CI 1.5-36.4) were independent predictors of prospective falls (area under the curve: 0.882).
  
  
  
  This study suggests that independent predictors of falls are dependent on frailty status. Among sensor-derived parameters, balance deficit, longer typical walking episodes, and shorter typical standing episodes were the most sensitive predictors of prospective falls in the combined pre-frail and frail sample. Gait deficit was not a sensitive fall predictor in the context of frailty status.
authors.affiliation: Arizona Center on Aging, College of Medicine, University of Arizona, Tucson, Ariz., USA.
authors.forename: M Jane
authors.initials: MJ
authors.lastname: Mohler
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Wendel
authors.forename: Ruth E
authors.initials: RE
authors.lastname: Taylor-Piliae
authors.forename: Nima
authors.initials: N
authors.lastname: Toosizadeh
authors.forename: Bijan
authors.initials: B
authors.lastname: Najafi
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control*; D000368:Aged; D000369:Aged, 80 and over; D003020:Clothing; D015444:Exercise; D016330:Frail Elderly; D015577:Geriatric Assessment; D006801:Humans; D009048:Motor Skills; D012111:Residence Characteristics; D012656:Self-Help Devices; D013647:Task Performance and Analysis; D016138:Walking