In-home Assessment of Turning and Transitions using Inertial Sensors in Older Adults with Dementia and Older Caregivers

Thesis (Master's)--University of Washington, 2016-06

University of Washington Abstract In-home Assessment of Turning and Transitions using Inertial Sensors in Older Adults with Dementia and Older Caregivers Jasjit Kaur Deol Chair of the Supervisory Committee: Ellen McGough, PT, PhD Assistant Professor Department of Rehabilitation Medicine This project consisted of two studies: Study 1 and Study 2. STUDY 1: Background/Objectives: Mobility problems progressively worsen with advancing stages of dementia. Cognitive decline, along with age-associated impairments in muscle weakness and balance, present significant challenges in the performance of everyday tasks which contribute to the incidence of falls. The aim of the study was to determine whether spatiotemporal parameters of turning and transitions differ between older adults with dementia compared to those without dementia, using portable inertial sensor technology in the home environment. Participants: Older adults with dementia [n=37 (Instrumented Timed-Up-and-Go), 29 (360° turns)] and caregivers [n=38 (Instrumented Timed-Up-and-Go), n=40 (360° turns)]. Outcomes Measures: Performance-based tests: Instrumented Timed-Up-and-Go (iTUG), and 360° turns clockwise (CW) and counterclockwise (CCW) and spatiotemporal measures of sit-to-stand, stand-to-sit, and turning were derived from the Ambulatory Parkinson’s Disease Monitoring (APDM) inertial sensors. Results: Participants with dementia took a significantly longer time to complete the sit-to-stand and stand-to-sit transitions compared to the caregivers (p < 0.05). However, there was no significant difference between the groups in trunk lean angle, average velocity or trunk displacement for either of the transitions between sitting and standing. Participants with dementia demonstrated a slower peak turning velocity and longer turning duration to complete the iTUG turn and 360° turns CW and CCW, compared to the older caregivers (p < 0.001). The mean turning angle was less (wider) in participants with dementia. Conclusion: Participants with dementia were slower while turning and transitioning between sitting and standing compared to the older caregivers. In addition, participants with dementia had a wider turning angle, suggesting differences in movement strategy. STUDY 2: Background/Objectives: With a surge in the number of studies utilizing the Ambulatory Parkinson’s Disease Monitoring (APDM) portable sensor system for investigation of movement in older adults, an investigation of concurrent validity between the laboratory-based motion analysis system (Qualisys, the criterion measure) and the APDM inertial sensor system (proposed alternative) is warranted. The aim of the study was to examine concurrent validity between measures of turning performance obtained from the APDM portable inertial sensor system and the laboratory-based motion analysis system, in people with mild cognitive impairment, in the laboratory setting. Participants: Older adults with mild cognitive impairment (MCI) [n=10]. Performance based tests: 360° turn counterclockwise (CCW) and spatiotemporal measures of turning derived from the APDM inertial sensors and the laboratory-based Qualisys motion analysis system. Results: Measures of turn duration and peak velocity demonstrated good to excellent positive correlations, r = 0.952, p < 0.001 and r = 0.976, p < 0.001, respectively. There was no correlation between the measure of turn angle obtained from the two motion analysis systems (rs = -0.139). Conclusions: Turn duration and peak velocity measures of APDM system demonstrate excellent correlation with Qualisys measures on the 360° turn, in older adults with MCI, in the laboratory. Further statistical analysis is needed to examine the absolute agreement on the turn angle measures.