title: Low physical function predicts either 2-year weight loss or weight gain in healthy community-dwelling older adults. the NuAge Longitudinal Study.
abstract: OBJECTIVE
  Weight change in older adults affects physical function (PF). However, data suggest that, conversely, PF may be a determinant of weight change. Our objective was to assess the role of baseline PF as a predictor of 2-year weight loss (WL) and weight gain (WG) ≥ 5% among healthy well-functioning community-dwelling older adults.
  
  
  METHODS
  The NuAge cohort (67-84 years) was classified into three groups according to the percent weight change over a 2-year follow-up: weight stable (weight change ≤ 2%; n = 629), WL ≥ 5% (n = 189), and WG ≥ 5% (n = 111). A summary measure of baseline PF was computed (sum of biceps, quadriceps, and grip strength, timed up and go, chair stand, normal and maximal gait speed, and balance performance scores [individual test score range = 0-4]; PF score range = 0-32). Multivariable logistic regression models separately assessed the relationships between baseline PF and 2-year WL and WG ≥ 5%.
  
  
  RESULTS
  Baseline PF was worse in both the WL (p < .001) and the WG (p = .001) groups compared with the weight stable group. In models adjusting for sex, age, body mass index, energy intake, depressive symptoms, and other significantly associated covariates, each 1-unit increase in standard deviation of PF was associated with decreased risk of either 2-year WL (odds ratio = 0.79, 95% CI = 0.63-0.99, p = .043) or WG (odds ratio = 0.74, 95% CI = 0.55-0.99, p = .041).
  
  
  CONCLUSIONS
  Low baseline PF was an independent common predictor of 2-year WL and WG ≥ 5% in the healthy well-functioning community-dwelling elderly population. Whether PF is an early cause or marker of weight change in this population remains to be determined.
authors.affiliation: Faculty of Medicine and Health Sciences, University of Sherbrooke and Research Centre on Aging, Health and Social Services Centre, University Institute of Geriatrics of Sherbrooke, 1036 rue Belvédère Sud, Sherbrooke, Québec, Canada.
authors.forename: Danielle
authors.initials: D
authors.lastname: St-Arnaud-McKenzie
authors.forename: Hélène
authors.initials: H
authors.lastname: Payette
authors.forename: Katherine
authors.initials: K
authors.lastname: Gray-Donald
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001132:Arm; D015331:Cohort Studies; D005260:Female; D005684:Gait; D006801:Humans; D057187:Independent Living; D007866:Leg; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D053580:Muscle Strength; D018482:Muscle, Skeletal; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012016:Reference Values; D013997:Time Factors; D015430:Weight Gain; D015431:Weight Loss