Wearable Sensors for Quantifying Deep Brain Stimulation Washout Effects on Gait in Parkinson'S Disease

OBJECTIVE: To evaluate gait changes in patients with Parkinson’s disease after turning off deep brain stimulation (DBS) using wearable movement sensors in order to assist DBS programming efforts in enhancing gait-related outcomes. BACKGROUND: Changes in DBS settings can have a delayed effect on gait function, which makes it impractical to optimize DBS for gait parameters in the clinic. Wearable movement sensors could be used to assess gait impairment in the patient’s home hours after treatment adjustments are made in the clinic. DESIGN/METHODS: Motion sensors were placed on the thighs and feet of patients with PD and implanted DBS systems. The patients completed lower extremity tasks from the Unified Parkinson’s Disease Rating Scale (UPDRS) motor assessment with DBS on and at a series of time points up to three hours after turning off DBS. Clinicians assessed impairment during these tasks using UPDRS guidelines. Changes over time in clinician and sensor impairment measures were evaluated. Additionally, sensor data was used to identify activity states (sitting still, moving while seated, standing still, or walking) as a measure of the patient’s overall mobility. RESULTS: Both clinician and sensor measurements captured impairment changes after turning off DBS. The activity state classification showed changes that correlated (r>0.7) with clinician measured changes in impairment and showed significant changes (p<0.05) between the DBS on and off states. CONCLUSIONS: Wearable movement sensors are sensitive to gait impairment changes in the home. These data could help clinicians optimize existing therapies for gait- related outcomes and aid in the development and evaluation of novel interventions for individuals with PD. Study Supported by: NIH/NIA 5R43AG033947. Disclosure: Dr. Brokaw has received personal compensation for activities with Great Lakes Neurotechnologies as an employee. Dr. Mera has received personal compensation for activities with Great Lakes NeuroTechnologies Inc. as an employee. Dr. Riley has received personal compensation for activities with Allergan Inc., Ipsen, Lundbeck, Merz Pharma and Teva Neuroscience. Dr. Riley has received research support from Cleveland Medical Devices. Dr. Walter has received personal compensation for activities with Deringer-Ney, Inc, Medtronic, Inc., Boehringer Ingelheim Pharmaceuticals Inc., and Teva Neuroscience. Dr. Espay has received personal compensation for activities with Solvay, Abbott, Chelsea Therapeutics, Teva Neuroscience, Eli Lilly & Company, Impax, Solstice Neurosciences, Novartis, the American Academy of Neurology, and the Movement Disorders Society. Dr. Espay has received research support from CleveMed/Great Lakes Neurotechnologies, Davis Phinney Foundation and Michael J. Fox Foundation. Dr. Revilla has nothing to disclose. Dr. Giuffrida has received personal compensation for activities with Great Lakes NeuroTechnologies Inc. as an employee. Dr. Giuffrida holds stock and/or stock options in Great Lakes NeuroTechnoliges Inc. which sponsored research in which Dr. Giuffrida was involved as an investigator. Dr. Heldman has received personal compensation for activities with Great Lakes NeuroTechnologies Inc. as an employee.