GUT-PD

Although Parkinson’s disease (PD) is commonly characterized as a movement disorder, it is also associated with important non-motor symptoms. Gastrointestinal dysfunction in PD may include constipation, weight loss, swallowing difficulties and excessive drooling of saliva. Constipation is often present before the onset of motor symptoms and has a significant impact on quality of life. Constipation is linked to changes in the composition of micro-organisms in the gut (the microbiome) and inflammation in the gut wall and there is increasing evidence that this might influence brain pathology in Parkinson’s via the ‘gut-immune-brain axis.’  

Gut

Proposed relationships between changes in the gut, inflammation and pathological changes in the brain in Parkinson’s disease. 

We are studying constipation and other gut symptoms in people with Parkinson’s disease over time in order to better define these problems and determine how they are linked to inflammation and disease progression. Key findings from our work so far include:

  • Using data from our long-term cohort studies, we have found that constipation in early PD is linked to faster progression to dementia over the next 8 years of follow-up. 
  • We have developed the Gastrointestinal Dysfunction Scale for Parkinson’s Disease (GIDS-PD) - a patient-reported outcome measure which evaluates PD-specific gut symptoms – to help us study gastrointestinal problems in Parkinson’s in a standardised and quantifiable way.
  • We have validated objective tools (methane breath tests and whole gut transit time) for use in gut research in PD. 
  • Using the GIDS-PD and a measure of whole gut transit time, we have characterized gastrointestinal symptoms across different disease stages and over time in PD. Our findings suggest that constipation does not develop in all people with PD, but only affects a subset, who are likely to experience it throughout the disease course.
  • We have shown that increased severity of constipation in people with PD is linked to higher levels of neuroinflammation in the brain, measured using [11C]PK11195 PET scanning. 
Gut

Dr Marta Camacho collecting samples for the Gut-PD study

 

This work has received funding from the Evelyn Trust and the NIHR Cambridge Biomedical Research Centre