Putative Cut-Points in Sarcopenia Components and Incident Adverse Health Outcomes: An SDOC Analysis

J Am Geriatr Soc. 2020 Jul;68(7):1429-1437. doi: 10.1111/jgs.16517. Epub 2020 Jul 7.

Abstract

Objectives: Analyses performed by the Sarcopenia Definitions and Outcomes Consortium (SDOC) identified cut-points in several metrics of grip strength for consideration in a definition of sarcopenia. We describe the associations between the SDOC-identified metrics of low grip strength (absolute or standardized to body size/composition); low dual-energy x-ray absorptiometry (DXA) lean mass as previously defined in the literature (appendicular lean mass [ALM]/ht2 ); and slowness (walking speed <.8 m/s) with subsequent adverse outcomes (falls, hip fractures, mobility limitation, and mortality).

Design: Individual-level, sex-stratified pooled analysis. We calculated odds ratios (ORs) or hazard ratios (HRs) for incident falls, mobility limitation, hip fractures, and mortality. Follow-up time ranged from 1 year for falls to 8.8 ± 2.3 years for mortality.

Setting: Eight prospective observational cohort studies.

Participants: A total of 13,421 community-dwelling men and 4,828 community-dwelling women. MEASUREMENTS Grip strength by hand dynamometry, gait speed, and lean mass by DXA.

Results: Low grip strength (absolute or standardized to body size/composition) was associated with incident outcomes, usually independently of slowness, in both men and women. ORs and HRs generally ranged from 1.2 to 3.0 for those below vs above the cut-point. DXA lean mass was not consistently associated with these outcomes. When considered together, those who had both muscle weakness by absolute grip strength (<35.5 kg in men and <20 kg in women) and slowness were consistently more likely to have a fall, hip fracture, mobility limitation, or die than those without either slowness or muscle weakness.

Conclusion: Older men and women with both muscle weakness and slowness have a higher likelihood of adverse health outcomes. These results support the inclusion of grip strength and walking speed as components in a summary definition of sarcopenia. J Am Geriatr Soc 68:1429-1437, 2020.

Keywords: gait speed; grip strength; hip fracture; mobility limitation; sarcopenia.

Publication types

  • Observational Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorptiometry, Photon
  • Accidental Falls
  • Aged
  • Body Composition / physiology
  • Body Mass Index
  • Consensus
  • Female
  • Hand Strength / physiology*
  • Hip Fractures
  • Humans
  • Independent Living
  • Male
  • Mobility Limitation
  • Muscle Strength / physiology*
  • Muscle Weakness / physiopathology*
  • Prospective Studies
  • Sarcopenia / diagnosis*
  • Sarcopenia / physiopathology
  • Walking Speed / physiology*

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