Development of an Objective Motor Score for Monitoring the Progression and Severity of Parkinson's Disease

Abstract

This thesis describes the development of an objective motor score (OMS) of Parkinson's disease that utilizes the Quantitative Motor Assessment Tool (QMAT) developed through efforts by the Intel Corporation and the Kinetics Foundation.Parkinson's disease (PD) is a movement disorder which is a member of a group of neurodegenerative diseases marked by the depletion or impairment of dopamineproducing cells in the brain. Since PD is chronic and degenerative, treatments are intended to either improve the quality of life for sufferers by superficially treating symptoms or slow and ultimately reverse the progression of the disease. No blood test or biomarker exists, so current assessment of the disease relies on a subjective tool called the Unified Parkinson's disease rating scale (UPDRS) which is a coarse scale that requires costly clinical administration and is subject to rater bias. The objective motor score described in this thesis exhibits excellent clinimetric properties, having demonstrated usability, validity, reliability, and responsiveness. It was calibrated to the motor section of the UPDRS, but in addition to high correlation with the motor UPDRS, it demonstrated an excellent ability to track deep brain stimulation treatment levels and to detect improvement in motor function of subjects due to dopaminergic treatment. With an excellent intraclass correlation coefficient, the OMS is a reliable measure and due to the objective nature of the test, it does not suffer from rater bias. Though these results come from the development phase, they suggest that confirmatory studies will firmly establish the excellent properties of the OMS.i While further studies are in motion to improve upon the sensitivity of the OMS by exploring metrics of voice recordings and paced tapping tests, the OMS presented here is a complete and usable tool for assessing the severity of PD-related symptoms. In conjunction with the QMAT, it is ready to be used in clinical trials, clinical practice, and even in the homes of patients who suffer from PD. This makes it an invaluable tool that could begin to replace the UPDRS for use in PD research, reducing costs and confounding factors in studies as well as extending their capabilities into the home.ii Acknowledgments