There is a clinical trial going on in France, which address this subject:
"Post-prandial Hypotension and Sleepiness in Parkinson's Disease and Other Synucleinopathies (HYPOSOMNPARK)"
Post-prandial Hypotension and Sleepiness in Parkinson's Disease and Other Synucleinopathies - Full Text View - ClinicalTrials.gov
One of the common features of PD is low blood pressure. It would probably be a good idea to have this checked.
John