EP 43. Impulse control disorder (ICD) and dopamine dysregulation syndrome (DDS) in Parkinson’s disease (PD) and deep brain stimulation surgery: A clinical Case

Abstract

Introduction The treatment of impulse control disorder (ICD) and dopamine dysregulation syndrome (DDS) in Parkinson’s Disease (PD) is complex. It was found in some series, that PD patients undergoing bilateral subthalamic nucleus DBS surgery (stn-DBS) that previously had ICD/DDS significantly improved of that domain after surgery. This fact has prompted a growing interest in the influence that STN-DBS surgery may have in these cases. Clinical case A 52 years-old patient with juvenile PD, onset at 42 years-old, with negative genetic study (parkin/LRRK2 mutations). Six years ago started to develop motor fluctuations, initially controlled with optimization of dopaminergic replacement therapy (DRT), but two years later starts to experience complex motor fluctuations, difficult to control with DRT. Progressively his family started to note some behavioural changes, namely, pathological gambling and hypersexuality, with marked disruption of social, familiar and work life. At this point, he was on 1510 mg equivalents of levodopa (LED), and 260 mg of LED in the form of ropinirole (extended release). The dopamine agonist was gradually suspended with progressive improvement of ICD symptoms. In the last year, he started to develop DDS, reaching to 2000–3000 mg/day of LED ingested through the form of short-acting formulations of levodopa, with disabling peak dose dyskinesia, frequent falls and functional impairment. Additionally, this patient had a motor response to a levodopa challenge of 60% (MDS-UPDRS-III), cognitively presented no significant changes (MoCA: 23; DRS-II; 138), reported no depression (BDI-II: 7) or apathy (AES-C: 27), and moderate ICD (QUIP Q: sexual and DDS domains impaired) and some non-motor symptoms/fluctuations (NMSS-PD: 23; Ardouin Scale: 42). He was then submitted to bilateral stn-DBS surgery. We will present the post-surgical outcome at 8 months. Conclusion Currently, there is not enough evidence in the literature to use stn-DBS surgery as a therapy for ICD/DDS. However, in patients who otherwise meet criteria for stn-DBS this procedure can also be helpful in controlling the symptoms of ICD/DDS, which can have a major impact on social, familiar and professional life as this case demonstrates.