Feasibility of dual-task gait to estimate Alzheimer's related cognitive decline in Down syndrome

Abstract

Introduction: The striatum and frontal lobes have been shown to have early Alzheimer's disease (AD) neuropathology and are critical for motor and cognitive function. We hypothesized gait would be associated with early-stage dementia in Down syndrome (DS), a cohort at risk for AD.

Methods: Twenty-eight participants with DS were enrolled in the study. Participants walked at their self-selected pace and while completing a dual task (counting, obstacle, or counting+obstacle).

Results: All participants were able to complete the self-paced condition and 78.57-96.42% completed the dual-task conditions. There was a trend for greater dual-task effects on gait velocity based on dementia diagnosis. Gait velocity had stronger associations with clinical dementia assessments than age or diagnosis.

Discussion: A dual-task gait paradigm is feasible to conduct with adults with DS and is associated with age and cognitive impairment. Dual-task gait may serve as an indicator of early stage dementia in DS.

Keywords: aging; dementia; dual‐task effect; gait speed; trisomy21.

FIGURE 1

GaitRite™ set‐up

FIGURE 2

Participant flowchart

FIGURE 3

Effect of condition on normalized velocity and step length. ***P < .001; **P < .01; *P < .05

FIGURE 4

Effect of age and condition on normalized velocity

FIGURE 5

Dual‐task effects on normalized velocity by diagnosis and intellectual disability. P < .01; ***P < .001; **P < .01; *P < .05. A, There was a trend for diagnosis to be associated with the degree of dual‐task effect observed. There was a trend for the uncertain/possible diagnosis group to experience a greater dual‐task effect than those with no dementia. B, Individuals with moderate intellectual disability (ID) had significantly less of a dual‐task effect than those with borderline/mild ID

FIGURE 6

Association between clinical and gait assessments. Note: While values on Y‐axis depict the raw scores of the Severe Impairment Battery (SIB) and the Dementia Questionnaire for People with Intellectual Disabilities (DMR), the Y‐axis has been transformed to reflect the non‐linear transformations used. A, There was a significant positive association between normalized velocity during the self condition and SIB total score. B, There was a significant positive association between normalized velocity during the self + counting condition and SIB total score. C, There was a significant negative association between normalized velocity during the self condition and DLD total score, whereby greater velocity was associated with less impairment