Standing, Transition, and Walking Ability in Older Adults: The Case for Independently Evaluating Different Domains of Mobility Function

Abstract

Background: Independent mobility is a complex behavior that relies on the ability to walk, maintain stability, and transition between postures. However, guidelines for assessment that details what elements of mobility to evaluate and how they should be measured remain unclear. Methods: Performance on tests of standing, sit-to-stand, and walking were evaluated in a cohort of 135 complex, comorbid, and older adults (mean age 87 ± 5.5 years). Correlational analysis was conducted to examine the degree of association for measures within and between mobility domains on a subset of participants (n = 83) able to complete all tasks unaided. Participants were also grouped by the presence of risk markers for frailty (gait speed and grip strength) to determine if the level of overall impairment impacted performance scores and if among those with risk markers, the degree of association was greater. Results: Within-domain relationships for sit-to-stand and walking were modest (rho = 0.01–0.60). Associations either did not exist or relationships were weak for measures reflecting different domains (rho = −0.35 to 0.25, p > 0.05). As expected, gait speed differed between those with and without frailty risk markers (p < 0.001); however, balance and sit-to-stand measures did not (p ≥ 0.05). Conclusions: This study highlights the need to independently evaluate different mobility domains within an individual as a standard assessment approach. Modest within-domain relationships emphasize the need to account for multiple, unique control challenges within more complex domains. These findings have important implications for standardized mobility assessment and targeted rehabilitation strategies for older adults.