A - 95 De Novo Impulse Control Symptoms in Parkinson’s Disease Patients Undergoing GPi-DBS: a Prospective Study

Abstract Objective Impulse control disorders (ICD) are behaviors characterized by a failure to resist an impulse to perform an action despite consequences. ICDs are an increasingly recognized complication of Parkinson’s Disease (PD) treatment1. Literature is mixed on the relationship between deep brain stimulation (DBS) and ICD2. Most studies focus on de novo ICD’s in patients undergoing subthalamic-nucleus (STN) DBS, but the relationship with globus pallidus interna (GPi) DBS is less understood. The present study examined rate and severity of ICD symptoms in patients undergoing GPi-DBS versus STN-DBS. Method 27 PD patients undergoing candidacy for bilateral DBS were prospectively enrolled. Pre-surgically, subjects underwent a neuropsychological evaluation and examination by a movement disorder specialist. 17 underwent STN-DBS and 10 underwent GPi-DBS. Subjects returned 12–18 months post-surgery to complete an abbreviated cognitive battery and an ICD rating scale. Results There were no differences in presurgical or postsurgical neurocognitive scores between groups. STN-DBS had higher pre-surgical ICD scores (p = 0.04) than GPi-DBS. Patients with post-DBS ICD’s were more likely to have undergone GPi-DBS than STN-DBS (p = 0.05). This finding persisted when controlling for change in levodopa equivalency dosage. Preoperatively, 41% of STN-DBS and 30% of GPi-DBS patients were ICD+. Postoperatively, 35% of STN-DBS and 80% of GPi-DBS patients were ICD+. Conclusion(s) Findings suggest patients undergoing GPi-DBS were more likely than those undergoing STN-DBS to develop de novo ICD’s. This is a novel finding in the literature and highlights the need for more research on the circuitry involved in GPi-DBS that may affect neuropsychiatric symptoms.