Early constipation predicts faster dementia onset in Parkinson's disease

Abstract

Constipation is a common but not a universal feature in early PD, suggesting that gut involvement is heterogeneous and may be part of a distinct PD subtype with prognostic implications. We analysed data from the Parkinson's Incidence Cohorts Collaboration, composed of incident community-based cohorts of PD patients assessed longitudinally over 8 years. Constipation was assessed with the MDS-UPDRS constipation item or a comparable categorical scale. Primary PD outcomes of interest were dementia, postural instability and death. PD patients were stratified according to constipation severity at diagnosis: none (n = 313, 67.3%), minor (n = 97, 20.9%) and major (n = 55, 11.8%). Clinical progression to all three outcomes was more rapid in those with more severe constipation at baseline (Kaplan-Meier survival analysis). Cox regression analysis, adjusting for relevant confounders, confirmed a significant relationship between constipation severity and progression to dementia, but not postural instability or death. Early constipation may predict an accelerated progression of neurodegenerative pathology.

Fig. 1. Survival analysis for major outcomes of Parkinson’s disease according to constipation severity.

Kaplan–Meier survival analysis for dementia (a), postural instability (b) and mortality (c) in groups stratified by constipation severity. (*, **, **** denote p ≤ 0.05, p ≤ 0.01, p ≤ 0.0001, respectively, log-rank test).