The gut-brain axis and Parkinson disease: clinical and pathogenetic relevance

Gastrointestinal disorders are one of the most significant non-motor problems affecting people with Parkinson disease (PD). Pathogenetically, the gastrointestinal tract has been proposed to be the initial site of pathological changes in PD. Intestinal inflammation and alterations in the gut microbiota may contribute to initiation and progression of pathology in PD. However, the mechanisms underlying this gut-brain axis in PD remain unclear. PD patients can display a large variety of gastrointestinal symptoms, leading to reduced quality of life and psychological distress. Gastrointestinal disorders can also limit patients' response to medications, and consequently negatively impact on neurological outcomes. Despite an increasing research focus, gastrointestinal disorders in PD remain poorly understood and their clinical management often suboptimal. This review summarises our understanding of the relevance of the gut-brain axis to the pathogenesis of PD, discusses the impact of gastrointestinal disorders in patients with PD, and provides clinicians with practical guidance to their management.

Automated summary

Gastrointestinal disorders are a significant issue for patients with Parkinson's disease, potentially caused by intestinal inflammation and changes in gut microbiota, but the mechanisms remain unclear. PD patients often experience a variety of gastrointestinal symptoms, impacting their quality of life. Despite research attention, understanding and management of gastrointestinal disorders in PD patients continue to be inadequate.