Psychostimulant effect of dopaminergic treatment and addictions in Parkinson's disease

Background : Dopamine replacement therapy in PD has been associated with both behavioral addictions and dopamine addiction. Objectives : To investigate potential association between l ‐dopa induced neuropsychiatric fluctuations and addictions in PD. Methods : A cohort of 102 patients with PD suffering from motor complications of l ‐dopa treatment was prospectively analyzed. We evaluated dopamine addiction, behavioral addictions, and neuropsychiatric fluctuations using the Ardouin scale of behavior in PD. Results : Patients with (n = 51) or without (n = 51) neuropsychiatric fluctuations did not differ in age, disease duration, medication, or UPDRS III motor score during on and off drug condition. Patients with neuropsychiatric fluctuations had a higher H & Y stage in off‐drug condition. A multivariate model showed that dopamine addiction (odds ratio: 8.9; P = 0.02) and behavioral addictions (odds ratio: 3.76; P = 0.033) were more frequent in the presence of neuropsychiatric fluctuations. Behavioral addictions and dopamine addiction were more frequent in the presence than in the absence of on‐drug euphoria (46% vs. 13.9%; P < 0.001 and 27% vs 6.2 %; P = 0.003), while conversely, no association emerged between dopamine or behavioral addictions and presence of off‐drug dysphoria. Patients with neuropsychiatric fluctuations had a poorer quality of life and a more frequent history of anxiety disorder. Conclusions : The psychostimulant effects of dopamine treatment during on‐drug euphoria, rather than avoidance of off‐drug dysphoria, appear to drive both behavioral addictions and abuse of medication. © 2017 International Parkinson and Movement Disorder Society