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bioRxiv · 10.1101/515155

Lower-limb rigidity is associated with frequent falls in Parkinson disease

McKay, J. L.·Hackney, M. E.·Factor, S. A.·Ting, L. H.
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Abstract

BACKGROUND AND OBJECTIVEThe role of muscle rigidity as an etiological factor of falls in Parkinson disease (PD) is poorly understood. Our objective was to determine whether lower leg rigidity was differentially associated with frequent falls in PD compared to upper limb, neck, and total rigidity measures. METHODS: We examined associations between UPDRS-III (motor) rigidity subscores and history of monthly or more frequent falls in N=216 individuals with PD (age, 66{+/-}10 y; 36% female, disease duration, 7{+/-}5 y) with logistic regression. RESULTS: N=35 individuals were frequent fallers. Significant associations were identified between lower limb rigidity and frequent falls (P=0.01) after controlling for age, sex, PD duration, total UPDRS-III score, and presence of FOG. No significant associations (P[≥]0.14) were identified for total, arm, or neck rigidity. CONCLUSION: Lower limb rigidity is related to frequent falls in people with PD. Further investigation may be warranted into how parkinsonian rigidity could cause falls.\n\nFinancial Disclosures/Conflict of Interest concerning the research related to the manuscript: None\n\nFundingNIH K25HD086276, R01HD046922, R21HD075612, UL1TR002378, UL1TR000454; Department of Veterans Affairs R&D Service Career Development Awards E7108M and N0870W, Consolidated Anti-Aging Foundation, and the Sartain Lanier Family Foundation.

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McKay, J. L., Hackney, M. E., Factor, S. A., Ting, L. H.. 2019-01-09. Lower-limb rigidity is associated with frequent falls in Parkinson disease. https://doi.org/10.1101/515155

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