Objective
To address a significant gap in research and clinical practice by developing the global conceptual definition of Sarcopenia.
Methodology
Study design
Two-phase Delphi study with participants from leading international musculoskeletal organisations and sarcopenia societies [1]. A steering committee was formed of representatives from each continent/region (Asia, Europe, North America, South America, New Zealand/Australia). The steering committee then developed a glossary of research terms on sarcopenia [2]. Following this, a list of statements on critical aspects of sarcopenia was developed and finalised.
Participants
Invitations to complete an online survey were sent to international experts from academic, industry, and healthcare professions. All participants including steering committee members completed a declaration of interest form prior to participation.
Statistical analysis
Prespecified criteria were set by the steering committee including a two-phase study design and an acceptable threshold of > 80% for accepted statements [1].
Findings
Participants
107 participants (64% men) from 29 countries and across 7 continents/regions completed the Delphi. The majority were residing in Europe (40%), Asia (22%) and North America (19%). Participants reported their primary role as academic professionals (76 [71%]), health professional (23 [22%), industry professionals (3 [2%]), or other-mixed (5 [5%]).
Accepted and rejected statements
Across the three facets of sarcopenia; ‘general aspects’, ‘components’ and outcomes’, 20 statements were accepted with strong agreement and 4 rejected with low agreement.
Figure 1 shows the list of accepted and rejected statements
Fig. 1.
The list of accepted and rejected statements from the Delphi study (n = 107 participants). Sourced from Kirk et al. [1]
Key points
General aspects
Sarcopenia is a disease of skeletal muscle; the definition will be the same for research and clinical practice; the definition will not depend on age, setting of care or clinical condition.
Components
The definition will comprise of both reduced muscle mass and strength, as well as muscle-specific strength. Physical performance will not be considered as a component of sarcopenia but instead as an outcome.
Outcomes
Sarcopenia increases a host of adverse health outcomes (e.g. fragility fractures, disability, poor quality of life), nursing home admissions and premature mortality. Impaired physical performance will be considered a measurable outcome of sarcopenia.
Figure 2 shows the global conceptual definition of sarcopenia that will be used to develop an operationalized definition
Fig. 2.
The global conceptual definition of Sarcopenia. Sourced from Kirk et al. [1]
Summary
The global conceptual definition of sarcopenia has been developed using an International Delphi Study including academic, industry and healthcare professionals from leading musculoskeletal organisations and sarcopenia societies. This inclusive approach will serve as a strong backbone to develop an operational definition of sarcopenia for research and clinical settings.
Future directions
Three working groups are currently underway to develop an operational definition of sarcopenia. These working groups, comprising of experts on specific sarcopenia topics including components and outcomes of the disease, are expected to finalise the operational definition in the coming year(s).
The Global Leadership Initiative in Sarcopenia (GLIS) represents a significant advancement in the field to improve the prevention, diagnosis and treatment of this muscle disease.
Acknowledgements
The list of societies and organisations taking part in the GLIS initiative
Aging in Motion (AIM) coalition/Alliance for Aging Research (AAR). American Geriatrics Society (AGS). American Society for Bone and Mineral Research (ASBMR). Asian Association for Frailty and Sarcopenia (AAFS). Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR). European Association for the Study of Obesity (EASO). European Geriatric Medicine Society (EuGMS). European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO). European Society for Clinical Nutrition and Metabolism (ESPEN)/ Global Leadership Initiative on Malnutrition (GLIM). Gerontological Society of America (GSA). International Association of Gerontology and Geriatrics (IAGG). International Conference on Frailty and Sarcopenia Research (ICFSR). International Osteoporosis Foundation (IOF). Society on Sarcopenia, Cachexia and Wasting Disorders (SCWD).
Author contributions
All authors contributed to the original manuscript
Data Availability
No datasets were generated or analysed during the current study.
Declarations
Conflict of interest
All authors declarations of conflicts of interests and declarations of sources of funding can be read here: https://www.eugms.org/fileadmin/images/news/2022/GLIS_Steering_Committee_Rev3.pdf
Footnotes
The list of societies and organisations taking part in the GLIS initiative are mentioned in Acknowledgements.
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Contributor Information
Alfonso J. Cruz-Jentoft, Email: alfonsojose.cruz@salud.madrid.org
The Global Leadership Initiative in Sarcopenia (GLIS) Group:
References
- 1.Kirk B, Cawthon PM, Arai H et al (2024) The conceptual definition of sarcopenia: Delphi consensus from the global leadership initiative in sarcopenia (GLIS). Age Ageing. 10.1093/ageing/afae052 10.1093/ageing/afae052 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Cawthon PM, Visser M, Arai H et al (2022) Defining terms commonly used in sarcopenia research: a glossary proposed by the global leadership in sarcopenia (GLIS) steering committee. Eur Geriatr Med 13:1239–1244. 10.1007/S41999-022-00706-5 10.1007/S41999-022-00706-5 [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
No datasets were generated or analysed during the current study.


