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.