Distinctive Pathophysiology Underlying Constipation in Parkinson’s Disease: Implications for Cognitive Inefficiency

Abstract

Depression is associated with constipation within and outside Parkinson’s disease (PD). Since inefficient cognitive-processing (bradyphrenia) features in PD and an enterokinetic agent improved cognitive performance in healthy individuals, bradyphrenia may be associated with constipation. We aim to define the archetypical bowel function of PD, and its association with cognition, mood, and motor features within and outside PD. We assessed colonic transit time (oral radio-opaque markers over 6 days), bowel function and psychometric questionnaires and measures of PD facets, including bradyphrenia, in 58 participants with diagnosed PD, and 71 without (controls). The best abdominal X-ray (day 7) predictors of PD status were total retained marker count and transverse colon segmental delay. However, Rome functional constipation status complemented segmental delay better, giving good specificity (85%) but low sensitivity (56%). Transverse colon marker count appeared to be age-associated only in PD. In PD, those correctly classified by bowel dysfunction had higher depression scores (p = 0.02) and longer cognitive-processing times than the misclassified (p = 0.05). Controls misclassified as PD by bowel dysfunction had higher depression and anxiety scores than the correctly classified (p = 0.002 and 0.003, respectively), but not slower cognitive processing. Measures of motor features were independent of sub-classification by bowel function in PD and in controls. In conclusion, constipation in PD has distinct localized pathophysiology, and is associated with bradyphrenia.

Influence of probiotic bacteria on gut microbiota composition and gut wall function in an in-vitro model in patients with Parkinson's disease

“…Because PD patients often have a degree of gut inflammation, faecal calprotectin is frequently raised ( Weis et al, 2019 ) and has been suggested as an early biomarker for PD risk ( Mulak et al, 2019 ). The GI abnormalities (particularly permeability issues and the finding of intestinal inflammation) found in PD are common to many other diseases, but their importance is that these changes may reflect pathophysiological processes that aggravate certain symptoms of PD ( Tucker et al, 2020a , Tucker et al, 2020b ).…”

Faecal metabolite deficit, gut inflammation and diet in Parkinson's disease: Integrative analysis indicates inflammatory response syndrome

“…Overgrowth in PD is likely to result from reflux of microbiota from a stagnant ascending colon. 1 Indeed, the higher prevalence of hydrogen breath test positivity with a lactulose substrate than when using the absorbable sugar, glucose, may represent distal colonisation. 13 …”

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“…However, absence of overall delay in colonic transit and of transverse colon segmental delay, irrespective of laxative use, had 90% specificity for excluding PD. 1 …”

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