Apraxia in Parkinson's Disease Patients With Deep Brain Stimulation

Deep brain stimulation (DBS) of the subthalamic nucleus or globus pallidus internus can improve motor symptoms Parkinson's disease (PD). However, it is not known whether DBS can help reduce the signs and symptoms of the limb-kinetic, ideomotor or ideational apraxia associated with PD or if apraxia can exist as a stimulation induced side effect from DBS therapy. In this study, we look to conduct a pilot study to examine the feasibility of characterizing the prevalence of apraxia in PD patients with chronic, stable DBS.

This will be a pilot study designed to assess the safety and feasibility of an apraxia testing protocol in chronically implanted PD DBS patients. We hypothesize that apraxia testing in the DBS ON and OFF states will be a safe and well-tolerated testing protocol. We also hypothesize that DBS will affect the severity of limb-kinetic, ideomotor and ideational apraxia in PD patients. This will set the foundation for larger prospective trials to further characterize apraxia in relation to DBS and whether or not DBS programming can modulate this phenomenon. In this study, we will recruit 60 PD patients with chronic, stable DBS of either the subthalamic nucleus (STN) or globus pallidus interna (GPi). Both unilateral and bilateral DBS patients are eligible for this study. For this study, "chronic, stable DBS" will be defined as patients who have had at least 6 months of optimization programming at the University of Florida. The subjects will be recruited to the Fixel clinic for a 1-day study visit in the medication ON state. The patients will undergo testing for limb-kinetic, ideomotor and ideational apraxia of both upper extremities in the DBS ON state at home therapeutic settings.