Diagnostic models excluding appendicular lean soft tissue mass demonstrated equivalent discrimination ability to those including ALSTM, raising questions about the necessity of ALSTM assessment for sarcopenia diagnosis.
Key Findings
Results
The diagnostic model excluding ALSTM was equivalent to the model including ALSTM in discriminating falls.
AUC [95% CI] for Model 1 (including ALSTM) was 0.61 [0.59, 0.64] for falls
AUC [95% CI] for Model 2 (excluding ALSTM) was 0.61 [0.58, 0.64] for falls
The difference in AUCs (Model 2 minus Model 1) was -0.004 [95% CI: -0.015, 0.006]
The confidence interval fell within the pre-specified equivalence margin of ±0.05
Falls were reported by 17.8% of the 2432 participants
Results
The diagnostic model excluding ALSTM was equivalent to the model including ALSTM in discriminating hospitalization.
AUC [95% CI] for Model 1 (including ALSTM) was 0.65 [0.62, 0.68] for hospitalization
AUC [95% CI] for Model 2 (excluding ALSTM) was 0.64 [0.61, 0.67] for hospitalization
The difference in AUCs (Model 2 minus Model 1) was -0.004 [95% CI: -0.014, 0.004]
The confidence interval fell within the pre-specified equivalence margin of ±0.05
Hospitalization was reported by 15.3% of participants
Methods
The study analyzed a large community-dwelling older adult cohort from the Itabashi Longitudinal Study on Aging in Tokyo, Japan.
A total of 2432 participants without missing data were analyzed
Median age was 76 years
53.2% of participants were men
Diagnostic models were based on the AWGS2019 criteria
ALSTM was assessed by bioelectrical impedance analysis
Methods
Model 1 included low handgrip strength/gait speed and low ALSTM, while Model 2 excluded low ALSTM, with equivalence assessed using 1000 bootstrap samples.
Two diagnostic models were developed based on AWGS2019 criteria
Differences in AUC and 95% confidence intervals between models were estimated using 1000 bootstrap samples
The pre-specified equivalence margin was ±0.05
Health-related outcomes were self-reported falls and hospitalization in the past year
Conclusions
The study raises questions about the clinical necessity of measuring appendicular lean soft tissue mass for sarcopenia diagnosis.
Both models showed similar and modest discriminative ability with AUCs around 0.61–0.65
The equivalence of the models was confirmed for both falls and hospitalization outcomes
Authors concluded that ALSTM assessment may not be necessary for sarcopenia diagnosis
The findings contribute to the long-standing geriatric debate about inclusion of ALSTM in diagnostic criteria for sarcopenia
Osuka Y, Hatanaka S, Kojima N, Shida T, Ohta T, Motokawa K, et al.. (2025). Is Appendicular Lean Soft Tissue Mass a Clinically Valid Diagnostic Marker for Sarcopenia?. Geriatrics & gerontology international. https://doi.org/10.1111/ggi.70252