Self‐reported rates of impulsivity in Parkinson’s Disease

Objective Impulsive decision‐making is characterized by actions taken without considering consequences. Patients with Parkinson's disease (PD) who receive dopaminergic treatment, especially dopamine agonists, are at risk of developing impulsive–compulsive behaviors (ICBs). We assessed impulse‐related changes across a large heterogeneous PD population using the Barratt impulsivity scale (BIS‐11) by evaluating BIS‐11 first‐ and second‐order factors. Methods We assessed a total of 204 subjects: 93 healthy controls (HCs), and 68 ICB– and 43 ICB + PD patients who completed the BIS‐11. Using a general linear model and a least absolute shrinkage and selection operation regression, we compared BIS‐11 scores between the HC, ICB– PD, and ICB + PD groups. Results Patients with PD rated themselves as more impulsive than HCs in the BIS‐11 total score, second‐order attention domain, and first‐order attention and self‐control domains. ICB + patients recorded higher total scores as well as higher scores in the second‐order non‐planning domain and in self‐control and cognitive complexity than ICB– patients. Interpretation These results indicate that the patients with PD show particular problems with attentional control, whereas ICB + patients show a distinct problem in cognitive control and complexity. Additionally, it appears that all patients with PD are more impulsive than their age‐ and sex‐matched healthy peers. Increased impulsivity may be a result of the disease course, or attributed to dopaminergic medication use, but these results emphasize the importance of the cognitive components of impulsivity in patients with PD.