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bioRxiv · 10.1101/146332

A Cross-Sectional Study of Set Shifting Impairments and Falling in Individuals with and without Parkinson’s Disease

McKay, J.·Lang, K. C.·Ting, L.·Hackney, M.
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Abstract

INTRODUCTION. Individuals with Parkinsons disease (PD) are at increased risk for falls, and exhibit deficits in executive function, including Set Shifting, which can be measured as the difference between parts B and A of the Trailmaking Test. METHODS. We conducted a cross-sectional study using baseline data of PD patients with and without freezing of gait (FOG) (n=69) and community-dwelling neurologically-normal older adults (NON-PD) (n=84) who had volunteered to participate in clinical rehabilitation research. Multivariate logistic regression analyses were performed to determine associations between Set Shifting, PD, and faller status, as determined by [&ge;]1 self-reported falls in the previous 6 months, after adjusting for demographic and cognitive factors and clinical disease characteristics. RESULTS. Impaired Set Shifting was associated with previous falls after controlling for age, sex, overall cognitive function, PD, FOG, and PD disease duration (OR=1.29 [1.03-1.60]; P=0.02). In models controlling for age, sex, and overall cognitive function, PD was associated with increased fall prevalence among the study sample (OR=4.15 [95% CI 1.65-10.44], P<0.01) and FOG was associated with increased fall prevalence among the PD sample (OR=3.63 [1.22-10.80], P=0.02). Although the strongest associations between Set Shifting and falling were observed among PD without FOG (OR=2.11) compared to HOA (OR=1.14) and PD with FOG (OR=1.46) in a multivariate model that allowed for interaction between set shifting and PD status, there was insufficient evidence to reject the null hypothesis of no interaction. CONCLUSIONS. Set Shifting is associated with previous falls in non-demented older adults with and without PD.\n\nHighlightsO_LIIndividuals with PD are at increased risk for falls, although causes are unclear.\nC_LIO_LIImpaired Set Shifting was associated with falls in older adults with and without PD.\nC_LIO_LIAssociations were strongest among those with PD but without freezing of gait.\nC_LI

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McKay, J., Lang, K. C., Ting, L., Hackney, M.. 2017-06-05. A Cross-Sectional Study of Set Shifting Impairments and Falling in Individuals with and without Parkinson’s Disease. https://doi.org/10.1101/146332

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