What determines gait speed in community-living older adults? A relative weight analysis.

Abstract

Purpose: Slower gait is prevalent in older adults. Multiple factors contribute to the slowness in older adults. However, whether these factors affect gait speed similarly or differently remains unknown. The primary purpose of this study was to explore the relative importance of eight modifiable factors (body mass index, leg muscle strength, power, dorsiflexion range of motion, tactile sensation, balance, fear of falling, and cognition) affecting gait speed in community-living older adults.

Methods: Eighty-five community-living older adults (mean ± standard deviation age: 72.3 ± 5.5 years; 51 females and 34 males) were enrolled in this cross-sectional study. A motion capture system assessed their gait speed. Those eight factors that could slow gait speed in older adults were also evaluated. A multiple linear regression model and relative weight analysis were utilized to determine the relative importance of each factor in contributing to the gait speed variation.

Results: All eight factors were significantly correlated with the gait speed. Together, they accounted for about 50% of the observed variation in gait speed. Six factors (body mass index, strength, power, range of motion, balance, and fear of falling) each explained a statistically significant portion of the gait speed variation. The most important factor was the leg muscle power (relative weight = 0.124), contributing 25.2% of the explained speed variation.

Conclusion: Leg muscle power could be a principal factor determining gait speed in older adults. Other factors also significantly influence gait speed in this population. The findings could guide prioritizing actions to improve gait speed in older individuals.