Motor Phenotype in Neurodegenerative Disorders: Gait and Balance Platform Study Design Protocol for the Ontario Neurodegenerative Research Initiative (ONDRI)

Abstract

Background:The association of cognitive and motor impairments in Alzheimer’s disease and other neurodegenerative diseases is thought to be related to damage in the common brain networks shared by cognitive and cortical motor control processes. These common brain networks play a pivotal role in selecting movements and postural synergies that meet an individual’s needs. Pathology in this “highest level” of motor control produces abnormalities of gait and posture referred to as highest-level gait disorders. Impairments in cognition and mobility, including falls, are present in almost all neurodegenerative diseases, suggesting common mechanisms that still need to be unraveled.Objective:To identify motor-cognitive profiles across neurodegenerative diseases in a large cohort of patients.Methods:Cohort study that includes up to 500 participants, followed every year for three years, across five neurodegenerative disease groups: Alzheimer’s disease/mild cognitive impairment, frontotemporal degeneration, vascular cognitive impairment, amyotrophic lateral sclerosis, and Parkinson’s disease. Gait and balance will be assessed using accelerometers and electronic walkways, evaluated at different levels of cognitive and sensory complexity, using the dual-task paradigm.Results:Comparison of cognitive and motor performances across neurodegenerative groups will allow the identification of motor-cognitive phenotypes through the standardized evaluation of gait and balance characteristics.Conclusions:As part of the Ontario Neurodegenerative Research Initiative (ONDRI), the gait and balance platform aims to identify motor-cognitive profiles across neurodegenerative diseases. Gait assessment, particularly while dual-tasking, will help dissect the cognitive and motor contribution in mobility and cognitive decline, progression to dementia syndromes, and future adverse outcomes including falls and mortality.

Motor and Cognitive Trajectories Before Dementia: Results from Gait and Brain Study

“…Serial assessments of motor performance seem to be critical for early detection of risk of dementia, particularly in older adults with initial normal gait velocity . Despite early studies showing that motor decline trajectories were more likely to be associated with non‐Alzheimer's dementias, mounting evidence suggests that motor impairment and declines are also associated with AD, which is aligned with our finding that 86% of participants who progressed to dementia progressed to AD …”

“…14,42 Despite early studies showing that motor decline trajectories were more likely to be associated with non-Alzheimer's dementias, 5,45 mounting evidence suggests that motor impairment and declines are also associated with AD, which is aligned with our finding that 86% of participants who progressed to dementia progressed to AD. 2,5,9,28,33,44,46,47 We have identified 2 patterns of declining trajectories, both associated with progression to dementia. In our cohort, the risk of progression to dementia was higher for motor than cognitive decline.…”

“…Dotted lines: (a) cognitive impairment can predict falls and fractures, (b) motor impairment can predict dementias. From Montero-Odasso et al 2,34,46 [Color figure can be viewed at wileyonlinelibrary.com] meaningful difference based on its association with higher risk of progression to mild cognitive impairment or mild dementia in community-dwelling older adults. 22 Motor decline was operationalized as a reduction of 10 cm/s or more in gait velocity between baseline and the final assessment.…”

“…Dotted lines: (a) cognitive impairment can predict falls and fractures, (b) motor impairment can predict dementias. From Montero‐Odasso et al …”

Subtle gait and balance impairments occur in idiopathic rapid eye movement sleep behavior disorder

“…Specifically, probable RBD patients showed a reduced cadence, longer swing time, and greater variability in swing time and double support time during normal walking when compared with the control participants . However, a more rigorous protocol including fast‐paced walking and dual tasking may identify more substantive gait abnormalities, as seen in PD by pushing performance to its limits and using a dual task to interfere with any compensatory strategies that may be masking underlying gait deficits . The primary aim of this study was to quantitatively determine any gait and balance impairments in a polysomnography‐confirmed cohort of iRBD patients by examining the differences between iRBD patients and healthy age‐matched controls across different walking and static balance conditions.…”