Calf circumference: clinical validation for evaluation of muscle mass in the elderly

OBJECTIVE To validate calf circumference as a technology for assessing muscle mass in the elderly. METHOD Cross-sectional study with 132 elderly people from Goiânia, Goias, Brazil. Decreased muscle mass was determined by the skeletal muscle mass index (IME) using Dual Energy X-Ray Absortometry (DEXA). The cutoff circumferences (CC) cutoff points to indicate muscle mass decrease were estimated by ROC curve, sensitivity, specificity and accuracy. RESULTS The most accurate cut-off points for detecting decreased muscle mass in the elderly were 34 cm for men (sensitivity: 71.5%, specificity: 77.4%) and 33 cm for women (sensitivity: 80.0%; specificity: 84.6%). CONCLUSION CC can be used as a measure for early identification of muscle mass decrease in routine evaluations of the elderly in primary care.