title: Baseline balance and functional decline in older adults with knee pain: the Observational Arthritis Study in Seniors.
abstract: OBJECTIVE
  To examine the cross-sectional and longitudinal effect of baseline balance, independent of multiple covariates (sociodemographic variables, comorbidities), on self-reported disability and several measures of functional performance.
  
  
  METHODS
  Observational Arthritis Study in Seniors was a community-based longitudinal study.
  
  
  METHODS
  Data collection was conducted at an exercise science research laboratory.
  
  
  METHODS
  A cohort of 245 women and 235 men, aged 65 and older, with self-reported knee pain.
  
  
  METHODS
  Measurements of balance, self-reported disability, functional performance, strength, sociodemographic characteristics, disease burden (including radiographic knee osteoarthritis (OA)), and functional limitations were obtained on participants at baseline and 30 months. The four outcome measures (self-reported disability, stair climb time, car time, preferred walking speed) were also collected at 15 months.
  
  
  RESULTS
  In cross-sectional analyses, baseline balance was significantly associated with each of the four outcome measures before adjusting for baseline knee strength. After adjusting for knee strength, baseline balance remained significantly associated with all functional performance outcomes and self-reported disability. In longitudinal analyses, baseline balance had a significant effect on car-time performance, whereby individuals in the lowest quartile of baseline balance scores declined in a quadratic manner from baseline to Month 30.
  
  
  CONCLUSIONS
  Baseline balance, independent of strength and various other covariates, is an important component of performance for transfer and ambulatory tasks and for self-reported disability. Balance was predictive of change in performance over time only in a task that presented a significant challenge to the lateral mobility/stability of participants. Balance was not predictive of decline in ambulatory performance-based tasks or in self-reported disability.
authors.affiliation: Department of Health and Exercise Science, Gymnasium Building Room 313, Wake Forest University, Winston-Salem, NC 27109, USA. marshap@wfu.edu
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Marsh
authors.forename: W Jack
authors.initials: WJ
authors.lastname: Rejeski
authors.forename: Wei
authors.initials: W
authors.lastname: Lang
authors.forename: Michael E
authors.initials: ME
authors.lastname: Miller
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Messier
mesh_terms: D000367:Age Factors; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D020370:Osteoarthritis, Knee / Q000503:physiopathology*; D010146:Pain / Q000503:physiopathology*; D004856:Postural Balance / Q000502:physiology*