Preliminary evaluation of the DDS-PC inventory: a new tool to assess impulsive-compulsive behaviours associated to dopamine replacement therapy in Parkinson's disease

Dopaminergic medications could increase the occurrence of a set of dysregulated behaviours in Parkinson's disease (PD), including reward-seeking behaviours (pathological gambling, hypersexuality, compulsive shopping, binge eating, reckless driving), punding and compulsive medication use. We report a preliminary evaluation of a questionnaire to assess the presence of these impulsive-compulsive behaviours associated to dopamine replacement therapy in PD. We screened 38 patients and their caregivers, comparing dopamine dysregulation syndrome (DDS) patients and non-DDS patients. The questionnaire was well accepted and demonstrated a preliminary good discriminant validity (p = 0.000). In addition, clinically relevant dysregulated condition is associated with a younger age (p = 0.006), younger age at disease onset (p = 0.001), levodopa-equivalent daily dose (p = 0.029), UPDRS III (p = 0.021), increased global psychopathology (interpersonal sensitivity and psychoticism), and differences in our inventory (p = 0.000). These preliminary results suggest that the DDS-PC inventory could help to identify patients experiencing impulsive-compulsive behaviours associated to DDS.