Arm circumference predicts 12-month mortality in older adults with hip fracture

Hip fractures (HF) in older adults are a major public health issue due to their high incidence and association with mortality and long-term disability. Simple bedside measures reflecting nutritional and muscular status-such as handgrip strength (HGS), arm circumference, and calf circumference-may help identify patients at higher risk of adverse outcomes. This study compared the predictive value of these parameters for 1-year mortality in older adults hospitalized for hip fracture.

We conducted a retrospective study on 295 patients aged ≥65 years admitted for fragility HF at the Azienda Ospedale-Università Padova. Demographic, clinical, and anthropometric data were collected at admission, along with a comprehensive geriatric assessment. Twelve-month mortality was the primary outcome. Prognostic value was assessed using ROC curves, Kaplan-Meier analysis, and multivariable Cox regression.

At 12 months, mortality was higher among patients with low arm (27.1%) and calf circumference (28.8%) (p = 0.008 and p = 0.010), while no difference was observed for HGS. ROC curve analysis showed that arm (AUC = 0.704, p < 0.001) and calf circumference (AUC = 0.634, p = 0.006) were associated with mortality, unlike HGS (p = 0.307). Kaplan-Meier survival analysis confirmed lower survival in patients with arm and calf circumference under 20th percentile, defined, respectively, low arm and calf (log-rank p = 0.003 and p = 0.02, respectively). In Cox models, low arm circumference remained independently associated with mortality across all adjustments (HR = 2.86; 95% CI 1.45-5.64; p = 0.002), whereas the association for calf circumference lost significance.

Arm circumference is a simple, cost-effective, and reliable bedside tool to help identify older adults at increased risk of mortality after HF.