A single-center, cross-sectional prevalence study of impulse control disorders in Parkinson disease: association with dopaminergic drugs

The current study aimed at establishing the prevalence of impulse control disorders (ICDs) in patients with Parkinson disease (PD) and their association with demographic, drug-related, and disease-related characteristics. We performed a single-center cross-sectional study of 805 PD patients. Impulse control disorders were investigated with the Questionnaire for Impulsive Compulsive Disorders in Parkinson's Disease; also comorbid neuropsychiatric complications (dementia, delusions, visual hallucinations) were investigated with clinical interviews and ad hoc instruments (Parkinson Psychosis Questionnaire and Neuropsychiatry Inventory). Impulse control disorders were identified in 65 patients (prevalence, 8.1%), with pathological gambling and hypersexuality the most frequent. Impulse control disorders were present in 57 of 593 cognitively preserved patients (prevalence, 9.6%) and in 8 of 212 demented patients (prevalence, 3.8%). Impulse control disorders were significantly associated with dopamine agonists (odds ratio [OR], 5.50; 95% confidence interval [CI], 2.60-12.46; P < 0.0001) and levodopa (OR, 2.43; 95% CI, 1.06-6.35; P = 0.034). Impulse control disorders frequency was similar for pramipexole and ropinirole (16.6% vs 12.5%; OR, 1.45; 95% CI, 0.79-2.74; P = 0.227). Additional variables associated with ICDs were male sex and younger age. These findings suggested that dopaminergic treatments in PD are associated with increased odds of having an ICD, but also other demographic and clinical variables are associated with ICDs, suggesting the multifactorial nature of the ICD phenomenon in PD.