Dysphagia and gastrointestinal disorders in Parkinson's disease: towards a diagnostic standard operating procedure for the interprofessional neurological outpatient care team.

Gastrointestinal Disorders in people with Parkinson's disease (PwP) are able to cause widespread clinical symptoms which can be challenging to classify in day-to-day clinical practice. In the upper gastrointestinal tract (GIT) oropharyngeal dysphagia, esophageal motility disorders as well as delayed gastric emptying may cause nutrition problems and reduce the efficacy of oral pharmacotherapy. In the lower GIT, bacterial overgrowth and prolonged colorectal transit times induce different stages of constipation leading to reduced quality of life and GIT comorbidities as well. Most of these symptoms reflect alpha-synuclein pathology in both the enteric nervous system and at various sites of the peripheral and central nervous systems. Besides, the growing use of various device aided therapies may additionally raise specific clinical questions about the interference with the GIT motility. This standard operating procedure (SOP) is intended to provide specific recommendations for diagnostic steps as well as therapeutic options, especially for interprofessional neurological outpatient care teams.