Resting-state functional magnetic resonance imaging in patients with Parkinson's disease with and without constipation: a prospective study.

Purpose: The etiology of constipation in Parkinson's disease is largely unknown. The aim of this study was to explore changes in regional neural activity and functional connections associated with constipation in a large cohort of individuals with Parkinson's disease.

Methods: We prospectively recruited 106 patients with Parkinson's disease with constipation and 73 patients with Parkinson's disease without constipation. We used resting-state functional magnetic resonance imaging for the first time to measure differences in regional neural activity and functional connections between the two patient groups.

Results: Patients with constipation showed significantly higher amplitude of low-frequency fluctuation than patients without constipation in the right dorsal pons extending into the cerebellum and in the right insula. The two types of patients also showed substantial differences in functional connections linking the superior temporal gyrus, particularly the right superior temporal gyrus, with multiple brain regions.

Conclusion: Regional neural activity and functional connectivity in the brain differ substantially between patients with Parkinson's disease with or without constipation. These findings provide a foundation for understanding the pathophysiology of constipation in Parkinson's disease and for identifying therapeutic targets.