PP285 - DIAGNOSTIC PERFORMANCE OF CALF CIRCUMFERENCE AND BMI-ADJUSTED CALF CIRCUMFERENCE FOR DETECTING LOW MUSCLE MASS USING SKELETAL MUSCLE INDEX

PP285

DIAGNOSTIC PERFORMANCE OF CALF CIRCUMFERENCE AND BMI-ADJUSTED CALF CIRCUMFERENCE FOR DETECTING LOW MUSCLE MASS USING SKELETAL MUSCLE INDEX

S. Pandey^1,*, S. Chopra¹, M. K. Singh², J. Sharma¹

¹Clinical Nutrition and Dietetics Department , ²Institute of Clinical Research, Medanta Hospital, gurugram, India

Rationale: Assessment of muscle mass is essential for diagnosing sarcopenia however, standard imaging modalities such as CT and MRI are costly and not routinely feasible. This study was done to evaluate and compare the diagnostic Performance of Calf Circumference (CC) and BMI-Adjusted Calf Circumference (BMI-CC) for Detecting Low Muscle Mass (LMM) Using Skeletal Muscle Index (SMI)

Methods: This cross-sectional study included 504 adults. CC was measured using standardized technique and BMI-CC based on reference criteria. SMI was assessed using bio-electrical impedance analysis (BIA), and handgrip strength (HGS) was measured using electronic dynamometer. LMM was defined according to AWGS 2019 criteria. Diagnostic performance was evaluated using sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy with 95% confidence intervals.

Results: Using SMI as the reference, CC demonstrated a balanced diagnostic profile with moderate sensitivity (63.54%) and high specificity (89.71%), achieving good overall accuracy (84.72%). BMI- CC and HGS showed higher sensitivity but lower specificity, indicating increased false-positive rates. Among combined approaches, the serial combination of CC and HGS yielded the highest specificity (93.87%) and strong confirmatory value but lower sensitivity (41.67%). In contrast, the parallel combination improved sensitivity (90.63%) and NPV (95.19%), making it effective for screening. The adjusted CC + HGS parallel combination achieved the highest sensitivity (92.71%) but had poor specificity (24.51%).

Conclusion: CC is a reliable standalone tool for ruling out low muscle mass, while its combination with HGS, particularly in parallel testing, enhances screening sensitivity. A stepwise, multimodal approach may improve diagnostic accuracy in clinical practice.

Disclosure of Interest: None declared