Abstract
Purpose
This study aimed to establish equations for estimating muscle mass through anthropometric parameters or together with physical function parameters in the community-dwelling older adults, providing a simple way of muscle mass assessment.
Methods
In this cross-sectional descriptive study, a total of 1537 older adults were recruited from the community and accepted the measurements of height, weight, upper arm and calf circumferences, grip strength, and walking speed. Body composition including appendicular skeletal muscle mass (ASM) was measured using bioelectrical impedance analysis (BIA). Participants were randomly divided into the development or validation group. Stepwise multiple linear regression was applied to develop equations in the development group. Thereafter, Pearson correlation coefficients, Bland-Altman plots, paired t-test, intraclass correlation coefficient (ICC) and paired-samples t-tests were used to assess the validity of the equations.
Results
All parameters were significantly correlated with ASM (r = 0.195~0.795, P < 0.001) except for the age in the validation group (P = 0.746). The most optimal anthropometric equation was: [adjusted R2 = 0.911, standard error of the estimate (SEE) = 1.311, P < 0.001]. Comparatively speaking, this equation showed high correlation coefficient (r = 0.951, P < 0.001) and ICC (ICC = 0.950, P < 0.001). No significant differences were found between BIA-measured ASM and the estimated ASM. The Bland-Altman plot showed that the mean difference between the estimated ASM and BIA-measured ASM was 0 kg and the limits of agreement of ASM was −2.70~2.60 kg. Furthermore, inclusion of physical function did not significantly improve the adjusted R2 and SEE.
Conclusion
The anthropometric equation offers a practical alternative simple and dependable method for estimating ASM in community-dwelling older adults.
Abbreviations
ASM, appendicular skeletal muscle mass; BIA, bioelectrical impedance analysis; DXA, dual-energy x-ray absorptiometry; ICC, intraclass correlation coefficient; BMI, body mass index; SEE, standard error of the estimate; LOA, limits of agreement; SD, standard deviation.
Data Sharing Statement
In attempt to preserve the privacy of individuals, clinical data will not be shared; the data can be available from the corresponding author on reasonable request authors upon request.
Ethics Approval and Consent to Participate
All participants were fully informed about the research purpose and characteristics before they provided signed consent. Ethical approval was granted from the Ethics Committee of Soochow University (ECSU-2019000161). This study conformed to the standards of the Declaration of Helsinki and was registered with Chinese Clinical Trial Registry (ChiCTR1900027960).
Acknowledgments
We would like to thank study participants who devoted their time and efforts.
Author Contributions
All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.
Disclosure
The authors report no conflicts of interest in this work.