Longitudinal Change in Calf Circumference and Incident Falls in Older Adults.

IMPORTANCE

Calf circumference (CC) is a simple, noninvasive proxy for lower-limb muscle mass. However, evidence on the longitudinal association between CC change and incident falls remains scarce.

OBJECTIVE

To investigate whether progressive decline in CC is associated with higher odds of incident falls among community-dwelling older adults.

DESIGN, SETTING, AND

PARTICIPANTS

This cohort study used data from the Chinese Longitudinal Healthy Longevity Survey, a nationally representative prospective cohort. Participants aged 60 years or older with complete CC measurements at baseline (2018) and follow-up (2021) were included. Data were analyzed from January to March 2026.

EXPOSURES: Absolute CC change (in centimeters) and relative CC change (as a percentage) over 3 years, analyzed as continuous and categorical variables (absolute: no decrease, <3 cm, 3 to <5 cm, ≥5 cm; relative: no decrease, <10%, 10% to <20%, ≥20%). The no-decrease group, including individuals with no change and those with increased CC, served as the reference group.

MAIN OUTCOMES AND MEASURES: The outcome of interest was incident falls, self-reported during the 2021 wave. Covariates included sociodemographic characteristics, falls history, health behaviors, functional status, and chronic diseases, all assessed via standardized questionnaires and evaluation. Odds of incident fall were assessed using inverse probability weighted logistic regression to address survival bias.

RESULTS

Among 7068 participants (mean [SD] age, 79.66 [10.32] years; 3835 [54.26%] female), 1671 participants (23.64%) reported incident falls over a median (IQR) follow-up of 3.07 (2.91-3.17) years. In fully adjusted models, each 1-cm absolute decrease in CC was associated with 3.2% higher odds of fall (odds ratio [OR], 1.03; 95% CI, 1.02-1.05) and each 10% relative decrease with 10.3% higher odds (OR, 1.10; 95% CI, 1.06-1.15). Compared with no decrease, an absolute decrease in CC of 5 cm or more was associated with 32.5% higher odds of fall (OR, 1.33; 95% CI, 1.10-1.60) and a relative decrease of 20% or more with 48.1% higher odds (OR, 1.48; 95% CI, 1.20-1.84).

CONCLUSIONS AND RELEVANCE: In this cohort study of older adults, longitudinal decreases in CC, both absolute and relative, were associated with higher odds of incident falls. Monitoring CC change over time may serve as a practical, low-cost measure to support fall risk assessment.