A Study to Assess Change in Sleep Disturbances of Adult Participants With Advanced Parkinson's Disease Receiving Subcutaneous Foslevodopa/Foscarbidopa

* Adult (age \>=18 years) Advance Parkinson's Disease (aPD) participants, diagnosed of levodopa-responsive idiopathic Symptoms PD (PD) prescribed on foslevodopa/foscarbidopa (LDp/CDp) Subcutaneous solution for infusion (SI) in routine clinical practice following approved Summary of product characteristics (SmPC) (levodopa-responsive Parkinson's disease with severe motor fluctuations and hyperkinesia or dyskinesia when available combinations of Parkinson medicinal products have not given satisfactory results). * MMSE\>=24 (cognitive cut point for the subjects to be able to comply with study procedures). * Decision to treat with LDp/CDp SI made by the clinician prior to any decision to approach the subject to participate in this study. * Particpants with moderate to severe obstructive sleep apnea (OSA) (Apnea-Hypoapnea Index (AHI)\>15) may be eligible if they comply with treatment (Continuous Positive Airway Pressure (CPAP) device used at least 4 hours/night and 70% of the nights during last month or mandibular advancement device (MAD)) and have an AHI \<15.

* Participants presenting with contraindications as per LDp/CDp SI SmPC. 2. * Participants participating in interventional research (not including non-interventional study, Post Marketing Observational Studies (PMOS), or registry participation) at time of enrollment visit.