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

## TL;DR

Measuring arm circumference in older adults with hip fractures can predict their risk of dying within a year, more reliably than other simple measures.

## Contribution

Arm circumference is shown to be an independent and reliable predictor of 12-month mortality in older hip fracture patients.

## Key findings

- Low arm and calf circumferences were significantly linked to higher 1-year mortality.
- Arm circumference remained an independent predictor of mortality after adjusting for other factors.
- Handgrip strength did not show any predictive value for mortality.

## Abstract

To evaluate and compare the prognostic value of arm circumference, calf circumference, and handgrip strength for 1-year mortality in older adults hospitalized for hip fracture.

Low arm and calf circumferences were significantly associated with increased 1-year mortality, while handgrip strength showed no predictive value. Arm circumference remained an independent predictor of mortality after full adjustment, whereas calf circumference did not.

Arm circumference is a simple, low-cost bedside tool that can reliably identify older hip fracture patients at increased risk of mortality.

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.