Global Cognition, Gender, and Level of Education Predict Dual-Task Gait Speed Variability Metrics in Older Adults.

INTRODUCTION: The purpose of this study was to determine if demographic variables and measures of cognitive function, functional mobility, self-reported balance self-efficacy, and self-reported physical activity can predict gait speed variability during single-task walking (STGSCV), during cognitive-motor dual-tasking (DTGSCV), and dual-task effect on gait speed variability (DTEGSCV) in older adults. METHODS: In 62 older adults, demographics were recorded and cognitive function (including the Montreal Cognitive Assessment, MoCA), functional mobility, balance self-efficacy (Activities-specific Balance Confidence Scale, ABC), and self-reported physical activity (Physical Activity Scale for the Elderly, PASE) were assessed. Three linear regression models were used to determine whether the functional mobility tests, PASE score, ABC score, and tests of cognitive function predicted gait speed variability outcomes (STGSCV, DTGSCV, DTEGSCV), with demographics included as covariates. RESULTS: MoCA score (p = 0.003), gender (p = 0.040), and years of education (p = 0.010) significantly predicted DTGSCV (R2 = 0.297, p = 0.002). MoCA score (p = 0.008) and years of education (p < 0.001) also significantly predicted DTEGSCV. Despite a significant regression model (R2 = 0.316, p = 0.001), there were no significant individual predictors of STGSCV. CONCLUSION: Older adults with lower cognitive function scores, according to the MoCA, and higher levels of education demonstrate larger gait speed variability during dual-tasking and may be at increased risk of real-world mobility issues or falling.

Including cognitive assessments with functional testing predicts capabilities relevant to everyday walking in older adults.

BACKGROUND: Dual-task (DT) testing reflects real-world walking demands in older adults but is not always feasible to perform in clinic. Whether clinical measures that predict single-task (ST) performance also predict DT performance or dual-task effects (DTEs) has not been fully explored. RESEARCH QUESTION: What are the relationships between cognitive performance, functional mobility, and self-reported physical activity and balance confidence and ST and DT Gait Speed and Cognitive Reaction Time, as well as DTEs on Gait Speed (DTEGS) and Cognitive Reaction Time (DTERT), in older adults? METHODS: Sixty-two older adults (71.5 ± 7.1 years, 17 males) completed cognitive performance, functional mobility, and self-report physical activity and balance confidence assessments. Three 1-min trials were performed: 1) ST Cognition (clock task), 2) ST Gait and 3) DT Cognition + Gait, with Cognitive Reaction Time (recorded during clock task performance via DirectRT) and Gait Speed (measured during walking trial via APDM system) recorded, and DTEGS and DTERT calculated, as the cognitive and gait outcomes. Six multivariate regressions were conducted to test whether cognitive performance, functional mobility, and self-report assessments predicted Gait Speed and Cognitive Reaction Time in ST and DT conditions and DTEs. RESULTS: The Comprehensive Trail Making Test (CTMT) predicted Reaction Time in ST cognitive (ß = - 0.525, p = .003) and DT (ß = - 0.510, p = .006) trials. The Physical Activity Scale for the Elderly (PASE) predicted DTERT (ß = - 0.397, p = .008). The 10-Meter Walk Test (10MWT) predicted Gait Speed in ST gait (ß = 0.692, p < .001) and DT (ß = 0.715, p < .001) trials. The Four Square Step Test (FSST) predicted ST Gait Speed (ß = - 0.233, p = .034). The Montreal Cognitive Assessment (MoCA) (ß = 0.293, p = .027), 10MWT (ß = 0.322, p = .046), and the FSST (ß = 0.378, p = .019) predicted DTEGS. SIGNIFICANCE: The 10MWT, CTMT, and MoCA can be easily implemented in the clinic and may be good choices to assess cognitive and functional abilities necessary for ambulation in older adults.

Acute effects of virtual reality treadmill training on gait and cognition in older adults: A randomized controlled trial.

INTRODUCTION: Everyday walking often involves walking with divided attention (i.e., dual-tasking). Exercise interventions for older adults should mimic these simultaneous physical and cognitive demands. This proof-of-concept study had a two-fold purpose: 1) identify acute cognitive and gait benefits of a single session of virtual reality treadmill training (VRTT), relative to conventional treadmill training (CTT), and 2) identify differences between those who reduced dual-task costs (i.e., responders) on gait or cognition and those who did not, after the session. METHODS: Sixty older adults were randomized to complete a single 30-minute session of VRTT (n = 30, 71.2±6.5 years, 22 females) or CTT (n = 30, 72.0±7.7 years, 21 females). Pre- and post-exercise session, participants performed single-task walking, single-task cognitive, and dual-task walking trials while gait and cognition were recorded. Gait variables were gait speed and gait speed variability. Cognition variables were response reaction time, response accuracy, and cognitive throughput. Dual-task effects (DTE) on gait and cognition variables were also calculated. RESULTS: Post-exercise, there were no group differences (all p>0.05). During single- and dual-task trials, both groups walked faster (single-task: F(1, 58) = 9.560, p = 0.003; dual-task: F(1, 58) = 19.228, p<0.001), responded more quickly (single-task: F(1, 58) = 5.054, p = 0.028; dual-task: F(1, 58) = 8.543, p = 0.005), and reduced cognitive throughput (single-task: F(1, 58) = 6.425, p = 0.014; dual-task: F(1, 58) = 28.152, p<0.001). Both groups also exhibited reduced DTE on gait speed (F(1, 58) = 8.066, p = 0.006), response accuracy (F(1, 58) = 4.123, p = 0.047), and cognitive throughput (F(1, 58) = 6.807, p = 0.012). Gait responders and non-responders did not differ (all p>0.05), but cognitive responders completed fewer years of education (t(58) = 2.114, p = 0.039) and better information processing speed (t(58) = -2.265, p = 0.027) than cognitive non-responders. CONCLUSIONS: The results indicate that both VRTT and CTT may acutely improve gait and cognition. Therefore, older adults will likely benefit from participating in either type of exercise. The study also provides evidence that baseline cognition can impact training effects on DTE on cognition.