Intercountry comparisons of advanced Parkinson's disease symptoms and management: Analysis from the OBSERVE‐PD observational study.

Objectives: In the absence of widely accepted criteria, determining when a patient with Parkinson's disease (PD) may benefit from more advanced treatments such as device‐aided therapy (DAT) so far remains a matter of physician judgment. This analysis investigates how classification of PD varies across countries relative to measures of disease severity. Materials and Methods: The OBSERVational, cross‐sEctional PD (OBSERVE‐PD) study included consecutive patients with PD at centers that offer DATs in 18 countries. In this subgroup analysis, we explore intercountry differences in identification of advanced versus non‐advanced PD based on physician's clinical judgment, symptoms assessed using Delphi consensus criteria, use of DAT, motor and non‐motor symptoms, and caregiver support. Demographic and clinical characteristics were obtained through review of medical records. Results: Overall, 1342 of 2615 patients (51.3%) were assessed by physicians as having advanced PD. The proportion of patients in different countries identified as having advanced PD (24.4–82.2%) varied. In 15 of 18 countries, a greater proportion of patients with advanced PD, according to select Delphi criteria, were identified by physicians as having advanced PD than with non‐advanced PD. There was a wide variability across countries in the proportion of patients with no dyskinesia, disabling dyskinesia, dyskinesia pain, and non‐motor symptoms who were identified by physicians as having advanced versus non‐advanced PD. Conclusions: The proportion of patients identified with advanced PD symptoms varies widely across countries, despite differences on the patients' profiles, indicating a need for objective diagnostic criteria to help identify patients who may benefit from DAT. [ABSTRACT FROM AUTHOR]