Background
Methods
Results
How to assess sarcopenia in clinical practice?
Applicable in research settings | Applicable in specialist clinical settings | Applicable in primary care settings | |
---|---|---|---|
Assessment of muscle mass | |||
DXA | +++ | +++ | + |
Anthropometric measurements | + | ++ | ++ |
CT-scan | +++ | ++ | + |
MRI | +++ | ++ | + |
BIA | ++ | ++ | + |
Assessment of muscle strength | |||
Handgrip strength | +++ | +++ | +++ |
Lower limb muscle strength | +++ | ++ | + |
Repeated chair stands test | + | + | ++ |
Assessment of physical performance | |||
Gait speed | +++ | +++ | +++ |
Timed Up and Go test | ++ | + | + |
Balance test | + | + | + |
6-min walk test | ++ | + | + |
400 m walk test | ++ | + | + |
Stair climb test | ++ | + | + |
SPPB test | +++ | ++ | + |
Assessment of muscle mass
In summary, we would propose assessing primarily muscle mass by DXA, if this tool is available, and if not, anthropometry measurements can easily be used, in primary care settings, as a first screening of patients with low muscle mass. These patients can then be referred for an additional evaluation in specialist clinical settings.
Assessment of muscle strength
In summary, we would recommend to measure muscle strength by handgrip strength in clinical practice (Table 1). For primary care settings where the availability of a handgrip dynamometer is not systematic, the repeated chair stand test could be used as an alternative measure of muscle strength.
Assessment of physical performance
In summary, we would propose that physical performance is primarily assessed in clinical practice by measuring gait speed. The SPPB test may be limited by the time of administration but might also be useful to identify men and women with low physical performance (Table 1).
The role of primary care physicians
The red flag method
Red flags | |
---|---|
Clinician’s observation | General weakness of the subject |
Visual identification of loss of muscle mass | |
Low walking speed | |
Subject’s presenting features | Loss of weight |
Loss of muscle strength, in arms or in legs | |
General weakness | |
Fatigue | |
Falls | |
Mobility impairment | |
Loss of energy | |
Difficulties in physical activities or activities of daily living | |
Clinician’s assessment | Nutrition |
Body weight | |
Physical activity |
The SARC-F questionnaire
Prediction of low muscle mass according to age and BMI
Anthropometric prediction equation in combination with a measure of muscle function
Prediction of sarcopenia using age, handgrip strength and calf circumference
How to manage sarcopenia in daily practice?
Identification of comorbidities
Physical activity
Nutrition
Pharmacological management
Mechanism of action | Drug name | Drug Developer | Indication sought | Study phase |
---|---|---|---|---|
I. Myostatin Antagonists | ||||
Activin receptor trap | ACE-031 | Acceleron | Duchenne muscular dystrophy | Phase 3 (trial terminated early) |
Myostatin antibody | REGN-1033 | Regeneron/Sanofi | Sarcopenia | Phase 2 |
LY-2495655 | Eli Lilly | Hip arthroplasty | Phase 2 | |
Elderly Fallers | ||||
Cancer Cachexia | ||||
PF-06252616 | Pfizer | Inclusion body myositis | Phase 1 | |
Activin receptor inhibitor | Bimagrumab (BMY338) | Novartis | Sarcopenia | Phase 2 and 3 |
Hip fracture | Phase 2 | |||
Cancer and COPD cachexia | ||||
II. Selective Androgen Receptor Modulators | Enobasarm (Ostarine) | GTx | Cancer Cachexia | Phase 3 (did not meet primary endpoint) |
III. Skeletal Troponin Activators | Tirasemtiv | Cytokinetics | ALS | Phase 2,3 |
CK-2017357 | Myasthenia Gravis |
Discussion and general consensus
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Several tools are currently available for the measurement of muscle mass, muscle strength and physical performance, with a potential use for the diagnosis and follow-up of sarcopenia but they are not fully adapted for widespread use in clinical daily practice. The recommended tools for the diagnosis of sarcopenia in specialist clinical practice are DXA for the measurement of appendicular muscle mass, grip strength for the measurement of muscle strength and gait speed for the measurement of physical performance. Thresholds previously recommended in the literature can be applied to distinguish normal from abnormal;
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Healthcare providers, particularly in primary care, should consider an assessment of sarcopenia in individuals at increased risk; suggested tools for assessing risk include the SARC-F questionnaire, the SMI method or different prediction equations based on anthropometric data associated with the measurement of handgrip strength, although all of them require further validation;
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Whereas further studies are required to provide a full evidence-based guidance to clinicians, current management can include physical activity advice, particularly progressive resistance training, treatment and prevention of vitamin D deficiency and adequate energy and dietary protein intake.