Impulse control disorders in Parkinson's disease: don't set your mind at rest by self‐assessments

Background and purpose Impulse control disorders ( ICD s) and related conditions in Parkinson's disease ( PD ) patients are frequent, disabling and sometimes devastating neuropsychiatric behaviors. Current knowledge on the prevalence of ICD s in PD is mainly based on assessments with questionnaires or patient interviews. This study was designed to evaluate the reliability of self‐assessed ICD s and related conditions in PD by exploring the agreement between self‐assessment of ICD s and related conditions in PD patients on the one hand and the estimation of their caregivers on the other hand. Methods After a short validation study of a novel ICD screening questionnaire, a cross‐sectional study in 150 PD patients was performed. All patients filled out the self‐assessment version of a screening questionnaire for ICD s, and caregivers completed an adapted version ( n  = 64). Results When comparing self‐assessments of PD patients and ratings by their caregivers, significant differences with regard to the estimated prevalence of hypersexuality (55% vs. 17%), dopamine dysregulation syndrome (31% vs. 3%) and punding (22% vs. 9%) were found. Conclusions Patients underestimate the presence and severity of some ICD s and related conditions, which shows how important assessments with caregivers are. After all, ICD s are probably much more frequent in PD than previously reported.