Impact of Edema on Length of Calf Circumference in Older Adults

Aim: Calf circumference, which is a known simple indicator of muscle mass, increases during edema. However, the extent to which edema increases calf circumference in older adults is unclear.

Methods: This retrospective cross-sectional study included patients aged ≥65 years whose nutritional status was assessed by nutrition support teams. Two different types of matching models in each sex were created according to the presence of edema on the right lower limb. All models were adjusted by age, body height, handgrip strength and performance status. Sarcopenia was diagnosed based on both reduced calf circumference and decline of handgrip strength. The prevalence of sarcopenia was estimated before and after adjustment for increment of calf circumference.

Results: In total, 2101 patients were included. Multifactor matching models showed that the mean difference in calf circumference between pairs was 1.6 cm (95% confidence interval [CI] 1.1-2.1, P < 0.001) for women and 2.1 cm (95% CI 1.6-2.7, P < 0.001) for men. The propensity score matching model similarly showed a mean difference of 1.6 cm (95% CI 1.1-2.1, P < 0.001) for women and 2.0 cm (95% CI 1.5-2.6, P < 0.001) for men. The prevalence of sarcopenia before and after adjusting for an edema-related increase in calf circumference was 42.6%/48.6% for women and 35.3%/38.5%-38.7% for men.

Conclusions: Edema in the lower limb increased the calf circumference by approximately 2 cm. When using calf circumference to assess muscle mass in patients with edema, the increase in circumference should be subtracted from the baseline circumference for an accurate assessment. Geriatr Gerontol Int 2019; 19: 993-998.