Clinical Approach to Impulse Control–Related Behavioral Disorders in Parkinson's Disease: A Scoping Review

BACKGROUND: Impulse control-related behavioral disorders refer to a group of compulsive behaviors seen in patients with Parkinson's disease (PD), comprising impulse control disorders (ICD), dopamine dysregulation syndrome (DDS), and punding. Over the years, numerous studies have been published on their prevalence, risk factors, neuroimaging, genetics, and management. More evidence now suggests that each disorder involves a distinct neurobiological mechanism. Although our understanding has improved, early recognition and appropriate treatment remain a significant challenge for clinicians, patients, and caregivers alike. OBJECTIVE: We aimed to summarize the definitions, underlying neurobiological mechanisms, validated assessment tools (for screening and rating), management strategies, and future directions for each of these impulse-control and related behavioral disorders (ICBD). METHODS: We performed a scoping review of PubMed, Embase, and psycINFO. RESULTS: A database search identified 540 articles, of which 110 were selected for full-text review. We classified the articles into 6 themes as follows: prevalence, risk factors, genetics, behavioral studies, neuroimaging, and treatment options. Based on the selected articles, we discussed the clinical phenotypes, pathophysiology, and treatment approaches for ICD, DDS, and punding. Identified knowledge gaps include the limited understanding of the pathophysiology of punding and validated rating scales for clinical use in assessing punding and DDS. Future research directions include investigating the role of selective serotonin 5-hydroxytryptamine 2A receptor inverse agonists, selective D1/D5 partial dopamine agonists, and transcranial magnetic stimulation in the treatment of ICBDs in PD. CONCLUSION: Early recognition and distinguishing among the different ICBDs are essential to enable early intervention, specific tailored management, and monitoring of these disorders and their respective treatment effects.