136 ASSOCIATIONS OF FRAILTY WITH CONSECUTIVE GAIT SPEED TRAILS MEASURED BOTH WITH AND WITHOUT ADDITIONAL STRESSORS

Abstract

Abstract Background Frailty is associated with gait speed and is defined as increased vulnerability to stressors. While usual gait speed is often measured, gait speed under additional stressors such as simultaneously reciting alternate letters of the alphabet (cognitive dual task) or walking at maximum pace are also measured. Consecutive trials may introduce an additional temporal stressor and we hypothesise that frailty may be associated with a greater reduction in walking speed across trials. Methods Data from community-dwelling adults aged 50+ years at Wave 3 of The Irish Longitudinal Study on Ageing were utilized. Using a 32-item frailty index (FI) we derived non-frail, pre-frail and frail groups. Gait speeds were measured using a 4.88 m walkway (GAITRite, CIR Systems, NY, USA). We examined differences in gait speed between two consecutive walks in three conditions (usual pace, cognitive dual task, and maximum pace) for the entire cohort, and by frailty group. Related-samples Wilcoxon signed rank tests were employed, with statistical significance set at P < 0.05. Results For the entire cohort, walk 2 speed for usual and cognitive conditions was higher by 1.0 cm/s (N = 4,097) and 1.1 cm/s (N = 3,927) respectively, and lower by 1.9 cm/s for maximum (N = 3,926). Stratified by FI, all groups walked more quickly in normal (1.0, 1.1, 1.2, respectively) and cognitive (1.3, 0.8, 0.5), and more slowly in maximum (−2.2, −1.6, −1.0). Conclusion In our analyses, higher frailty seemed to be associated with a higher increase for the usual walk, a smaller increase for the cognitive walk, and a smaller decrease in maximum speed. The clinical significance of the differences was very small. However, our results support that in research and clinical practice, frailty by FI should not be expected to lead to a different pattern of gait speed change across consecutive trials.