Is Motor Side Onset of Parkinson's Disease a Risk Factor for Developing Impulsive‐Compulsive Behavior? A Cross‐Sectional Study

Many studies have investigated impulsive compulsive behavior (ICB) occurring under dopamine replacement therapy (DRT) in Parkinson’s disease (PD), but few have considered the influence of asymmetrical dopaminergic denervation on ICB. Based on the Ardouin’s Scale of Behavior in Parkinson’s Disease (ASBPD), we compared the frequency of ICB in two groups: 142 right onset of PD (RPD) patients and 163 left onset of PD (LPD) patients recruited between January 2012 and January 2015. Inclusion criteria were: diagnosis of PD; disease duration ≥5 years; and right-handed patient. Noninclusion criteria were: dementia and DBS. Sociodemographic data and declarative hemibody side onset of PD were collected. Levodopa equivalent daily doses (LEDs), on-medication UPDRS-III score, laterality score using items 20 to 26 of the UPDRS-III, and total ICB score by adding all the ASBPD hyperdopaminergic items were calculated. As previously reported, ICB cases were defined by at least one score ≥ 3 or at least two scores ≥2 at the ASBPD items reflecting ICB. An ICB-free patient was defined by all hyperdopaminergic items that were < 2 on the ASBPD and no more than two items with a score equal to 1. Patients were divided into two groups according to declarative data regarding onset of the disease: RPD and LPD. The local ethics committee approved the study, and the patients gave written informed consent. Statistical Analysis System (release 9.3; SAS Institute Inc., Cary, NC) software was used. For quantitative variables with normal distribution, we used a t test to compare values of the means from two independent groups; otherwise, the nonparametric Wilcoxon rank-sum test was applied. Chi-square and Fisher’s exact tests were used to test for differences in