Associations of 2 Established Methods of Measuring Gait Speed and Sit-To-Stand Performance with Frailty and Life-Space Mobility in Community-Dwelling Older Adults.

Objectives: The 4-m gait speed (4mGS) and 10-m gait speed (10mGS) tests and the 30-second sit-to-stand (30sSTS) and 5-times sit-to-stand (5xSTS) tests are commonly used and advocated in consensus recommendations. We compared these tests on their predictive and clinical value concerning the risk of prefrailty/frailty and restricted life-space mobility (RLSM).

Design: Cross-sectional study.

Setting And Participants: A sample of 1235 community-dwelling adults (mean ± SD, 68 ± 7 years) participated in this prospective cohort study.

Methods: At baseline assessment, participants completed a survey and functional assessment, from which gait speed, sit-to-stand performance, self-reported mobility limitation, 40-item Frailty Index, and Life Space Assessment were measured. Participants with a 40-item Frailty Index >0.15 and a Life Space Assessment <60 points were classified as having prefrailty/frailty and RLSM, respectively. At 1-year follow-up assessment, prefrailty/frailty and RLSM were evaluated.

Results: Correlations between gait speed and sit-to-stand measures were high (ρ values >0.80). In multivariable ordinal models, these measures added incremental prognostic value beyond a base model comprising demographics and self-reported mobility limitation variables in predicting baseline and 1-year outcomes. Between 10mGS and 4mGS, models with 10mGS had higher concordance indices (differences, 0.005-0.009), and these differences translated to generally greater net benefit in decision curve analyses. Between 30sSTS and 5xSTS measures, no one measure consistently outperformed the other, with small net benefit differences between measures (<0.2%).

Conclusions And Implications: In community-dwelling older adults, gait speed and sit-to-stand measures meaningfully predicted prefrailty/frailty and RLSM. 10mGS provided more robust prognostic information than the 4mGS, whereas 5xSTS and 30sSTS measures showed near equivalence of performance. These findings could guide the choice of functional measures in clinical and research settings.