title: Monitoring 6-month trajectory of grip strength improves the prediction of long-term change in grip strength in disabled older women.
abstract: BACKGROUND
  This study aims to assess the degree and heterogeneity of decline in grip strength in the short term (6 months) and the clinical relevance of short-term decline to long-term decline (2.5 years) in grip strength in disabled older women.
  
  
  METHODS
  Eighty-four community-dwelling disabled women aged 65 years or older were evaluated on a weekly basis over 6 months, followed by an additional five semi-annual visits for a total follow-up of 3 years. The study outcome is maximum isometric handgrip strength in the nondominant hand. Linear random effects models were used to characterize population- as well as individual-level change in grip strength over time.
  
  
  RESULTS
  In the weekly assessments over the initial 6 months, individual-level short-term change in grip strength was detectable (mean = -0.12 kg/month; p = .06), heterogeneous (range: -2.03 ± 0.95 kg/month), and independent of absolute grip strength at baseline (mean = 18.4 kg). Additionally, among women with grip strength greater than 16.7 kg at baseline, the long-term rate of decline in grip strength was accelerated by 0.15 kg/year (p = .014) for every 0.5 standard deviation (0.25 kg/month) increase in the short-term rate of decline. The baseline absolute grip strength, however, was not significantly associated with the long-term rate of decline (correlation = -0.36, p = .105).
  
  
  CONCLUSIONS
  Our findings suggest that short-term change in grip strength is detectable and meaningful for disabled older women and it is the individual's past trajectory of grip strength relative to her current strength level, not her current absolute strength per se, that is important for predicting future strength decline.
authors.affiliation: Division of Geriatric Medicine and Gerontology, Department of Medicine, School of Medicine, Johns Hopkins University, Baltimore, Maryland. Center on Aging and Health, Johns Hopkins Medical Institutions, Baltimore, Maryland. qxue@jhsph.edu.
authors.forename: Qian-Li
authors.initials: QL
authors.lastname: Xue
authors.affiliation: Division of Gerontology, Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Guralnik
authors.affiliation: Baltimore VA medical Center Geriatric Research Education and Clinical Centers and the Division of Geriatric Medicine and Gerontology, Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland.
authors.forename: Brock A
authors.initials: BA
authors.lastname: Beamer
authors.affiliation: Mailman School of Public Health, Columbia University, New York, New York.
authors.forename: Linda P
authors.initials: LP
authors.lastname: Fried
authors.affiliation: Benjamin Leon Family Center for Geriatric Research and Education, Department of Medicine, Herbert Wertheim College of Medicine, Florida International University, Miami, Florida.
authors.forename: Paulo H M
authors.initials: PH
authors.lastname: Chaves
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015331:Cohort Studies; D006233:Persons with Disabilities; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D012737:Sex Factors; D013997:Time Factors
keywords: Aging; Muscle weakness; Sarcopenia.