Exploring the Association Between Measures of Obesity and Measures of Trip-induced Fall Risk Among Older Adults

Abstract

Objective: To explore the association between measures of obesity and measures of trip-induced fall risk among community-dwelling older adults.

Design: Case-control.

Setting: Gait laboratory.

Participants: Voluntary sample of 55 community-dwelling older adults (aged ≥65y; N=55) with body mass index (BMI) of 18.84-44.68 kg/m².

Interventions: Not applicable.

Main outcome measures: Measures of obesity included 6 anthropometry-based measures (BMI; thigh, hip and waist circumferences; ratio of waist-to-hip circumference; index of central obesity) and 4 dual-energy x-ray absorptiometry-based measures (percentage trunk, leg, and total fat; fat mass index). Measures of risk of tripping during overground walking included median and interquartile range of toe clearance and area under the swing phase toe trajectory. Measures of trip recovery after a laboratory-induced trip included trunk angle and angular velocity at ground contact of the first recovery step, anteroposterior distance from stepping foot to center of mass at the same instant, and step time of the first recovery step.

Results: Risk of tripping was associated with waist-to-hip ratio and thigh circumference. After grouping participants by waist-to-hip ratio, those with high ratios (≥0.9 cm for men and ≥0.85 cm for women) exhibited significantly greater variability in toe clearance. Trip recovery was associated with hip circumference, thigh circumference, fat mass index, and total fat. After grouping participants by fat mass index, those with high indices (>9 kg/m² for men and >13 kg/m² for women) exhibited less favorable trunk kinematics after a laboratory-induced trip (Cohen d=0.84).

Conclusions: Waist-to-hip ratio and fat mass index may more closely relate to trip-induced fall risk than BMI among community-dwelling older adults.

Keywords: Accidental falls; Aging; Biomechanical phenomena; Body composition; Body mass index; Gait; Obesity; Obesity, abdominal; Rehabilitation.