Over half of patients with Parkinson’s disease (PD) develop symptoms of psychosis during the course of their disease. Existing guidelines include recommendations for managing symptoms of psychosis in patients with PD. However, the extent to which such recommendations translate to clinical practice in major European nations is unclear. The current study describes trends in the clinical management of patients diagnosed with PD psychosis (PDP) based on survey responses and patient chart reviews from 437 neurologists across France, Germany, Italy, Spain, and the UK (collectively, the EU-5). Surveyed neurologists reported that PDP typically manifests four or more years after the diagnosis of PD, with the most commonly reported initial symptoms being moderately disruptive visual hallucinations, agitation, and illusions/false sense of presence. PD medications adjustment was the most common first-line intervention, applicable to an estimated 59–79% of patients for the initial management of PDP depending on country. Responses from surveyed neurologists suggest PD medications adjustment is a temporary solution for many patients with PDP and that there is considerable variability in subsequent lines of intervention. The current report provides a resource for understanding the patterns of care and treatment for PDP across these major European nations.

Parkinson's disease psychosis (PDP) is a clinical condition that affects patients diagnosed with Parkinson's disease (PD) and has a spectrum of neuropsychiatric symptoms distinct from the hallmark motor symptoms. Although prior studies have reported on the prevalence of PDP in select European nations, variations in study design complicate study-to-study comparisons. In this study, we surveyed 1,667 medical practitioners across France, Germany, Italy, Spain, and the UK (collectively, the EU-5) to estimate the prevalence of PDP or symptoms of psychosis among patients with PD. Analysis of the survey data suggest approximately 29% of the general PD population in the EU-5 exhibit signs of PDP. Among the PD population, country-specific rates of PDP are estimated at 30% in France, 27% in Germany, 34% in Italy, 30% in Spain and 21% in the UK. These rates appear in line with those reported in prior country-specific studies. Results from the subset of 437 neurologists who proceeded to take the full survey suggest the symptoms of PDP are disruptive to patients or their respective caregivers in approximately 53% of cases. These results provide a resource that enables cross-country comparison of PDP rates across these major European nations.