Calf Circumference Measurement Protocols for Sarcopenia Screening: Differences in Agreement, Convergent Validity and Diagnostic Performance

Abstract

Background Although recommended by the Asian Working Group for Sarcopenia 2019 consensus (AWGS’19) as a screening tool for sarcopenia, there remains no consensus regarding the position (sitting, standing) or laterality (right, left) for the measurement of calf circumference (CC). This study aimed to determine the agreement between CC measurements, correlations with muscle mass and function, and diagnostic performance for sarcopenia screening. Methods We studied 176 healthy community-dwelling older adults (mean age, 66.8±7.1 years) from the GERILABS-2 study. CC was measured using non-elastic tape in four ways: left and right sides in the sitting and standing positions. Sarcopenia was diagnosed using the AWGS’19 criteria. We produced Bland-Altman plots to assess the agreement, partial correlations for muscle mass and function to compare convergent validity, and area under the receiver operating characteristic curve (AUC) to compare diagnostic performance. Results The prevalence rate of sarcopenia was 17.4%. Sitting CC was larger than standing regardless of laterality (right 35.31±2.95 cm vs. 34.61±2.74 cm; left 35.37±2.96 cm vs. 34.70±2.83 cm; both p0.05). The optimal cutoff was <34 cm for all measurements, except for the left standing position (cutoff <35 cm). Conclusion Standing CC measurements are recommended for sarcopenia screening in community-dwelling older adults because of their good agreement without systematic bias, convergent validity, and diagnostic performance.

Keywords

• sarcopenia
• screening
• protocol