The Instrumented Stand and Walk (ISAW) test to predict falls in older men

Area of Science:

• Gerontology
• Biomechanics
• Clinical Biomechanics

Background:

• Balance and gait impairments are common precursors to falls in older adults.
• Objective measures offer potential for improved prediction of future fallers.
• The Instrumented Stand and Walk Test (ISAW) utilizes wearable sensors to comprehensively assess balance and gait domains.

Purpose of the Study:

• To evaluate if ISAW objective measures enhance fall prediction in high-functioning older men.
• To compare the predictive power of ISAW metrics against traditional fall history, gait speed, and dual-task cost.
• To identify key ISAW metrics contributing to accurate fall risk assessment.

Main Methods:

• Recruited 214 high-functioning older men (mean age 82 years).
• Administered the ISAW test, including 30s stance, 7m walk, turn, and return, using inertial sensors.
• Analyzed 17 ISAW metrics using regression models to predict falls within 12 months, comparing models with and without age and fall history.

Main Results:

• The ISAW test improved faller prediction compared to age and fall history alone (AUC increased from 0.69 to 0.75).
• Top models incorporated postural sway, turning, gait variability, and gait initiation measures.
• Gait speed and dual-task cost did not significantly distinguish fallers from non-fallers in this cohort.

Conclusions:

• Objective ISAW measures significantly enhance the prediction of future falls in high-functioning older men.
• A multi-domain approach, assessing sway, turning, variability, and initiation, is crucial for accurate fall risk identification.
• Simple measures like gait speed are insufficient for predicting falls in this population, highlighting the complexity of fall etiology.