Clinical and research interest in sarcopenia has burgeoned internationally, Asia included.
The Asian Working Group for Sarcopenia (AWGS) 2014 consensus defined sarcopenia as
"age-related loss of muscle mass, plus low muscle strength, and/or low physical performance"
and specified cutoffs for each diagnostic component; research in Asia consequently
flourished, prompting this update. AWGS 2019 retains the previous definition of sarcopenia
but revises the diagnostic algorithm, protocols, and some criteria: low muscle strength
is defined as handgrip strength <28 kg for men and <18 kg for women; criteria for
low physical performance are 6-m walk <1.0 m/s, Short Physical Performance Battery
score ≤9, or 5-time chair stand test ≥12 seconds. AWGS 2019 retains the original cutoffs
for height-adjusted muscle mass: dual-energy X-ray absorptiometry, <7.0 kg/m2 in men
and <5.4 kg/m2 in women; and bioimpedance, <7.0 kg/m2 in men and <5.7 kg/m2 in women.
In addition, the AWGS 2019 update proposes separate algorithms for community vs hospital
settings, which both begin by screening either calf circumference (<34 cm in men,
<33 cm in women), SARC-F (≥4), or SARC-CalF (≥11), to facilitate earlier identification
of people at risk for sarcopenia. Although skeletal muscle strength and mass are both
still considered fundamental to a definitive clinical diagnosis, AWGS 2019 also introduces
"possible sarcopenia," defined by either low muscle strength or low physical performance
only, specifically for use in primary health care or community-based health promotion,
to enable earlier lifestyle interventions. Although defining sarcopenia by body mass
index-adjusted muscle mass instead of height-adjusted muscle mass may predict adverse
outcomes better, more evidence is needed before changing current recommendations.
Lifestyle interventions, especially exercise and nutritional supplementation, prevail
as mainstays of treatment. Further research is needed to investigate potential long-term
benefits of lifestyle interventions, nutritional supplements, or pharmacotherapy for
sarcopenia in Asians.