title: Grip Strength Decline and Its Determinants in the Very Old: Longitudinal Findings from the Newcastle 85+ Study.
abstract: BACKGROUND
  Weak grip strength (GS) is a key component of sarcopenia and frailty and a powerful predictor of mortality, morbidity and disability. Despite increasing interest in understanding GS across the lifespan, little is known about GS decline in the very old (aged ≥85). We examined trajectories of GS in very old adults and identified the determinants.
  
  
  METHODS
  GS (kg) was measured four times over 5 years in 319 men and 526 women participating in the Newcastle 85+ Study. A weak GS sub-cohort was identified as having strength of ≤27 kg (men), and ≤16 kg (women) at baseline and follow-up. Mixed models were used to establish trajectories of GS and associated factors in all participants, men and women, and in those with weak GS.
  
  
  RESULTS
  Men's mean grip strength was 24.42 (SD = 6.77) kg, and women's 13.23 (4.42) kg (p<0.001) at baseline, with mean absolute change of -5.27 (4.90) kg and -3.14 (3.41), respectively (p<0.001) by 5-year follow-up. In the time-only mixed model, men experienced linear annual decline in GS of -1.13 (0.8) kg (β (SE), p<0.001), whilst women's decline although slower, accelerated by -0.06 (0.02) kg (p = 0.01) over time. In the saturated model, higher baseline physical activity, height, fat-free mass, better self-rated health, and not having arthritis in hand(s) were associated with stronger GS initially in both sexes. Annual GS decline in men and participants with weak GS who were highly physically active was slower by 0.95 and 0.52 kg, respectively compared with inactive counterparts.
  
  
  CONCLUSIONS
  Grip strength decline in the very old followed linear (men) and curvilinear (women) trends. High levels of physical activity were protective of GS loss in men (but not in women) and in those with weak GS. Thus maintaining muscle strength in later life is important to reduce the morbidity and mortality in the very old.
authors.affiliation: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.|NIHR Newcastle Biomedical Research Centre in Ageing and Chronic Disease, Newcastle University, and Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne, United Kingdom.|Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.
authors.forename: Antoneta
authors.identifier: http://orcid.org/0000-0001-9247-899X
authors.initials: A
authors.lastname: Granic
authors.affiliation: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.|NIHR Newcastle Biomedical Research Centre in Ageing and Chronic Disease, Newcastle University, and Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne, United Kingdom.|Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.
authors.forename: Karen
authors.initials: K
authors.lastname: Davies
authors.affiliation: Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.|Institute of Health and Society, Newcastle University, Baddiley-Clark, Richardson Road, Newcastle upon Tyne, United Kingdom.
authors.forename: Carol
authors.initials: C
authors.lastname: Jagger
authors.affiliation: Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.|Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Thomas B L
authors.initials: TB
authors.lastname: Kirkwood
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, United Kingdom.
authors.forename: Holly E
authors.initials: HE
authors.lastname: Syddall
authors.affiliation: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom.|NIHR Newcastle Biomedical Research Centre in Ageing and Chronic Disease, Newcastle University, and Newcastle upon Tyne NHS Foundation Trust, Newcastle upon Tyne, United Kingdom.|Newcastle University Institute for Ageing, Campus for Ageing and Vitality, Newcastle upon Tyne, United Kingdom.|MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, United Kingdom.|NIHR Collaboration for Leadership in Applied Health Research and Care, Wessex, University of Southampton, Southampton, United Kingdom.
authors.forename: Avan A
authors.initials: AA
authors.lastname: Sayer
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male