Impulse control disorders and pathological gambling in patients with Parkinson disease

Objectives: The primary aim of this article is to critically review the clinical features and comorbidities, epidemiology, pathophysiology, and treatment of impulse control disorder (ICD) associated with Parkinson disease (PD). Methods: References for this review were identified by searches of PubMed from 1980 until January 2008 with the terms Parkinson disease, impulse control, pathologic gambling, hypersexuality, levodopa, and dopamine agonists. Articles were also identified through searches of the authors' own files. Only papers published in English were reviewed. Results: Pathologic gambling has emerged as one of the most prominent ICDs, although hypersexuality, compulsive shopping and other manifestations of obsessive-compulsive disorder may also dominate PD-related behavioral manifestations. Affected patients may demonstrate a pattern of self-escalation of dopaminergic medication dosing which may lead to a state of dependency. Conclusions: Patients most commonly affected by ICD, such as pathologic gambling and hypersexuality, are males who develop PD at a younger age, and those with a previous history of mood disorder, alcohol abuse, or obsessive-compulsive disorder. Dopamnergic drugs, particularly dopamine agonists, play an important role in triggering these nonmotor symptoms.