Addiction and Parkinson's disease

Abstract

Parkinson's disease (PD) is a neurodegenerative disease characterized by tremor, rigidity, and akinesia. PD patients are commonly treated by dopamine replacement therapy (DRT). The degeneration of the dopaminergic system and the longstanding exposure to DRT may cause, in a group of vulnerable patients, dysregulation of the brain reward system. These patients develop DRT-related compulsions, which include addiction to levodopa or dopamine dysregulation syndrome (DDS), punding, and impulse control disorders (ICDs). ICDs or behavioral addiction reported in PD include pathological gambling, hypersexuality, compulsive buying, and binge eating. Although the underlying pathophysiology is still poorly understood, these behaviors are linked by their reward-based and repetitive nature. Such behaviors may result in psychosocial impairment for the patients and are often hidden. The recognition of these behaviors is important and allows a better clinical management. Although the limited data do not permit particular therapeutic strategies, some approaches are worth considering: DRT reduction, trials of nondopaminergic medications and subthalamic chronic stimulation.