title: Impulse control disorders and levodopa-induced dyskinesias in Parkinson's disease: an update.
abstract: Dopaminergic medications used in the treatment of patients with Parkinson's disease are associated with motor and non-motor behavioural side-effects, such as dyskinesias and impulse control disorders also known as behavioural addictions. Levodopa-induced dyskinesias occur in up to 80% of patients with Parkinson's after a few years of chronic treatment. Impulse control disorders, including gambling disorder, binge eating disorder, compulsive sexual behaviour, and compulsive shopping occur in about 17% of patients with Parkinson's disease on dopamine agonists. These behaviours reflect the interactions of the dopaminergic medications with the individual's susceptibility, and the underlying neurobiology of Parkinson's disease. Parkinsonian rodent models show enhanced reinforcing effects of chronic dopaminergic medication, and a potential role for individual susceptibility. In patients with Parkinson's disease and impulse control disorders, impairments are observed across subtypes of decisional impulsivity, possibly reflecting uncertainty and the relative balance of rewards and losses. Impairments appear to be more specific to decisional than motor impulsivity, which might reflect differences in ventral and dorsal striatal engagement. Emerging evidence suggests impulse control disorder subtypes have dissociable correlates, which indicate that individual susceptibility predisposes towards the expression of different behavioural subtypes and neurobiological substrates. Therapeutic interventions to treat patients with Parkinson's disease and impulse control disorders have shown efficacy in randomised controlled trials. Large-scale studies are warranted to identify individual risk factors and novel therapeutic targets for these diseases. Mechanisms underlying impulse control disorders and dyskinesias could provide crucial insights into other behavioural symptoms in Parkinson's disease and addictions in the general population.
authors.affiliation: Department of Psychiatry and Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge, UK; Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK. Electronic address: vv247@cam.ac.uk.
authors.forename: Valerie
authors.initials: V
authors.lastname: Voon
authors.affiliation: Departments of Pharmacology and Psychiatry, Center for Compulsive Behavior and Addiction, Rush University Medical Center, Chicago, IL, USA.
authors.forename: T Celeste
authors.initials: TC
authors.lastname: Napier
authors.affiliation: Department of Cognitive, Linguistic and Psychological Sciences and Department of Psychiatry and Human Behavior, Brown Institute for Brain Science, Providence, RI, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Frank
authors.affiliation: Institut des Sciences Cognitives Marc Jeannerod, CNRS, Bron, France; Université Claude Bernard Lyon 1, Villeurbanne, France.
authors.forename: Veronique
authors.initials: V
authors.lastname: Sgambato-Faure
authors.affiliation: Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Grace
authors.affiliation: Biodonostia Health Research Institute, University Hospital Donostia, and Basque Center on Cognition, Brain and Language, San Sebastián, Spain; Ikerbasque-Basque Foundation for Science, Bilbao, Spain; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto Carlos III, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Rodriguez-Oroz
authors.affiliation: Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas, Instituto Carlos III, Spain; HM Centro Integral de Neurociencias, HM Puerta del Sur, Mostoles and Centro de Estudios Universitarios-San Pablo University, Madrid, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Obeso
authors.affiliation: Université de Bordeaux, Institut des Maladies Neurodégénératives, Bordeaux, France; Centre National de la Recherche Scientifique, Institut des Maladies Neurodégénératives, Bordeaux, France.
authors.forename: Erwan
authors.initials: E
authors.lastname: Bezard
authors.affiliation: Université de Bordeaux, Institut des Maladies Neurodégénératives, Bordeaux, France; Centre National de la Recherche Scientifique, Institut des Maladies Neurodégénératives, Bordeaux, France.
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Fernagut
mesh_terms: D000978:Antiparkinson Agents / Q000009:adverse effects*; D007174:Disruptive, Impulse Control, and Conduct Disorders / Q000139:chemically induced*; D004409:Dyskinesia, Drug-Induced / Q000209:etiology*; D006801:Humans; D007980:Levodopa / Q000009:adverse effects*; D010300:Parkinson Disease / Q000188:drug therapy
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa