Impulse control and related behaviors in Parkinson's disease with dementia

Background and purpose The objective was to determine the frequency, demographic and clinical correlates [such as age, sex, Parkinson's disease (PD) severity and dopaminergic treatment] of impulse control disorder (ICD) symptoms and related behaviors in patients with PD with (PD-D) and without (PD-ND) dementia. Methods We analyzed historical data from a national, multi-center, cross-sectional database and assessed ICDs and related behaviors with the Scale for Evaluation of Neuropsychiatric Disorders in Parkinson's Disease administered as a semi-structured interview to patients with PD-D (n = 85) and PD-ND (n = 444) and their informants. Results Dopamine agonist therapy use was common and similar in the two groups (78.8% in PD-D vs. 82.9% in PD-ND), but ICDs (23.5% vs. 13.3%, P = 0.02), hobbyism-punding (32.9% vs. 10.6%, P < 0.001) and dopaminergic medication abuse (8.2% vs. 3.2%, P = 0.03) were more common in the PD-D group. Conclusions The finding that ICDs and related behaviors are more common in patients with PD frequently treated with dopamine agonists who also have comorbid dementia suggests that the neural substrates associated with PD dementia may also predispose to development of compulsive behaviors.