title: Agreement and Predictive Validity Using Less-Conservative Foundation for the National Institutes of Health Sarcopenia Project Weakness Cutpoints.
abstract: OBJECTIVE
  To derive lean mass cutpoints based on a less-conservative Foundation for the National Institutes of Health (FNIH) Sarcopenia Project Weakness cutpoint for grip strength (WeakI) and to assess their agreement with European Working Group on Sarcopenia in Older People (EWGSOP) and prediction of incident slow walking and mortality.
  
  
  METHODS
  Longitudinal analysis.
  
  
  METHODS
  Baltimore Longitudinal Study of Aging.
  
  
  METHODS
  Individuals aged 65 and older (287 men, 258 women) with 2 to 10 years of follow-up.
  
  
  METHODS
  Weakness was determined according to handgrip strength using a hand dynamometer, appendicular lean mass (ALM) using dual-energy X-ray absorptiometry, and walking speed according to 6-m usual pace walk speed. Analyses were performed using classification and regression tree analysis, Cohen's kappa, and Cox models.
  
  
  RESULTS
  Cutpoints derived from WeakIfor ALM (ALMI) were less than 21.4 kg in men and less than 14.1 kg in women and for ALM adjusted for body mass index (ALM/BMII) were less than 0.725 in men and less than 0.591 in women. Kappas with EWGSOP were 0.65 for men and 0.75 for women for ALMIand 0.34 for men and 0.47 for women for ALM/BMII. Men with WeakI+ ALMIwere twice as likely to develop slow walking as those not weak with normal ALMI(Hazard ratio (HR) = 2.44, 95% confidence interval (CI) = 1.02-5.82). Under EWGSOP, men with weakness and low RALM were almost 3 times as likely to develop slow walking as those not weak with normal RALM (HR = 2.91, 95% CI = 1.11-7.62). Neither approach predicted incident slow walking in women.
  
  
  CONCLUSIONS
  The ALMIcutpoints agree with EWGSOP and predict slow walking in men. Future studies should explore sex differences in the relationship between body composition and physical function and the effect of change in muscle mass on muscle strength and physical function.
authors.affiliation: Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
authors.forename: Nancy
authors.initials: N
authors.lastname: Chiles Shaffer
authors.affiliation: Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
authors.forename: Luigi
authors.initials: L
authors.lastname: Ferrucci
authors.affiliation: Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
authors.forename: Michelle
authors.initials: M
authors.lastname: Shardell
authors.affiliation: Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Simonsick
authors.affiliation: Longitudinal Studies Section, Translational Gerontology Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Studenski
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D001823:Body Composition / Q000502:physiology*; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D018908:Muscle Weakness / Q000503:physiopathology; D009316:National Institutes of Health (U.S.); D015203:Reproducibility of Results; D055948:Sarcopenia / Q000175:diagnosis* / Q000503:physiopathology; D014481:United States; D000072797:Walking Speed / Q000502:physiology*
keywords: aging; muscle; sarcopenia; weakness