title: Association between a history of falls and the ability to multi-task in community-dwelling older people.
abstract: OBJECTIVE
  Many older people fall when they perform tasks which require increased attention. The aim of this study was to determine differences in reaction times, during simple-, dual- and triple-task conditions requiring differing levels of motor coordination, balance control and cognitive attention, between groups of fallers and non-fallers in community-dwelling older individuals.
  
  
  METHODS
  The study involved the recruitment of 87 older individuals living at home, 57 women and 30 men aged 75 to 91 years. Reaction times, measured by pushing a handheld button as quickly as possible in response to a visual stimulus, were measured in four conditions: 1) quiet standing (simple-task); 2) counting backward during quiet standing (dual-task with cognitive demand); 3) stepping in place (dual-task with balance demand); and 4) counting backward while stepping in place (triple-task with cognitive and balance demands).
  
  
  RESULTS
  Twenty-nine (33.3%) participants had fallen at least once during the past year. There were no statistically significant differences in reaction times between non-fallers and fallers during any of the tasks. Reaction times were significantly longer during the dual- and triple-tasks compared with the simple-task conditions in both groups. The ratio between reaction times during dual-tasks with balance demands (stepping in place) and those in the simple-task condition were significantly related to a history of falls and showed the highest odds ratio (OR 3.16, 95% CI 1.06- 9.45, p=0.04).
  
  
  CONCLUSIONS
  Relative changes in reaction times during a dual-task with balance demands were related to a history of falls in community-dwelling older individuals. Reaction times in dual-task conditions with a balance demand were more sensitive to past falls than those during a dual-task with cognitive demands.
authors.affiliation: Section for Health Promotion, Department of Health and Medical Care, Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka-machi, Obu, Aichi, 474-8511, Japan. makizako@ncgg.go.jp
authors.forename: Hyuma
authors.initials: H
authors.lastname: Makizako
authors.forename: Taketo
authors.initials: T
authors.lastname: Furuna
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Shimada
authors.forename: Hikaru
authors.initials: H
authors.lastname: Ihira
authors.forename: Mika
authors.initials: M
authors.lastname: Kimura
authors.forename: Eiichi
authors.initials: E
authors.lastname: Uchiyama
authors.forename: Lars I E
authors.initials: LI
authors.lastname: Oddsson
mesh_terms: D000058:Accidental Falls; D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D004856:Postural Balance; D011930:Reaction Time; D013647:Task Performance and Analysis