Phenotyping Motor-subtypes of Parkinsonism from Full-body Kinematics using Machine Learning (P6-11.007)

Abstract

<h3>Objective:</h3> The purpose of this study is to use whole-body kinematics data during walking to accurately identify motor subtypes of Parkinson’s disease (PD) and parkinsonism. <h3>Background:</h3> Two major motor subtypes of PD have been described, Postural Instability and Gait Disorder (PIGD) and Tremor Dominant (TD), which differ in the disease prognosis. Prior studies have explored quantifying motor subtypes via gait analysis, which lacks data for whole-body movements that are required when analyzing an entire gait cycle. In this study, we measure whole-body kinematics while walking, which is then analyzed to classify PIGD vs. TD subtypes using machine learning (ML) models. <h3>Design/Methods:</h3> The whole-body kinematic marker time series were collected from 57 patients (including 5 patients with atypical parkinsonism) while walking in off medication state using a motion capture system from 2015 to 2017. From all marker kinematics data, we extracted various features beyond gait-related features, including time series and spectral features. Then, ML models were used to classify the extracted features into the corresponding motor subtypes assessed with Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). <h3>Results:</h3> Compared to the clinically assessed motor subtypes, our model classified whole-body kinematics while walking with a 97.0% F1 score, which significantly outperformed the gait-based analysis which showed a 55.8% F1 score. Both upper and lower body movements were found to be useful indicators to distinguish between PIGD and TD. <h3>Conclusions:</h3> Our findings strongly supported our hypothesis that accurately quantifying motor subtypes requires more than gait-related or lower-body movement features that are typically used in previous work. This feature analysis may lead to novel hypotheses for fine-grained upper-body motion phenotypes related to motor subtypes. More importantly, our techniques can help monitor changes in motor subtypes for guiding appropriate intervention through objective quantification of walking movements. <b>Disclosure:</b> The institution of an immediate family member of Mr. Gong has received research support from National Science Foundation. Dr. Kwon has nothing to disclose. Prof. Clifford has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Alivecor. Prof. Clifford has stock in Mindchild Medical. Prof. Clifford has received intellectual property interests from a discovery or technology relating to health care. Prof. Clifford has received publishing royalties from a publication relating to health care. Dr. Esper has received research support from Centers for Disease Control and Prevention. Dr. Esper has received publishing royalties from a publication relating to health care. Dr. Factor has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Acorda. Dr. Factor has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Sunovion. Dr. Factor has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Alterity. Dr. Factor has received personal compensation in the range of $10,000-$49,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Lundbeck. Dr. Factor has received personal compensation in the range of $5,000-$9,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Biogen. The institution of Dr. Factor has received research support from Impax. The institution of Dr. Factor has received research support from Biohaven. The institution of Dr. Factor has received research support from Sunovion. The institution of Dr. Factor has received research support from Vaccinex. The institution of Dr. Factor has received research support from Voyager. The institution of Dr. Factor has received research support from Neurocrine. The institution of Dr. Factor has received research support from US World Meds. The institution of Dr. Factor has received research support from Addex. The institution of Dr. Factor has received research support from Prelinia. The institution of Dr. Factor has received research support from Medtronics. The institution of Dr. Factor has received research support from Boston Scientific. Dr. Factor has received publishing royalties from a publication relating to health care. Dr. Factor has received publishing royalties from a publication relating to health care. Dr. Factor has received publishing royalties from a publication relating to health care. Dr. Factor has received publishing royalties from a publication relating to health care. Dr. McKay has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Biocircuit Technologies. The institution of Dr. McKay has received research support from NIH. The institution of Dr. McKay has received research support from the McCamish Foundation.