Submitted by lac59 on Tue, 20/05/2025 - 13:47
Marta Camacho from the Williams-Gray lab has published a new paper defining the characteristics of gut dysfunction in Parkinson's disease. The role of gut dysfunction and its links to neurodegeneration is a very topical issue, with wide interest from both researchers and the media.
In this Q&A Marta explains her research, why there is so much interest in it right now, the implications for developing new therapies for Parkinson's which target gut health, and how by exploring digestive symptoms we can improve patient care.
Read the full paper published on Nature: NPJ - Parkinson's Disease: The profile of gastrointestinal dysfunction in prodromal to late-stage Parkinson’s disease | npj Parkinson's Disease
Q&A with Marta Camacho
Why is this research area so important right now?
Despite the incredible attention that the gut-brain axis has received in recent years, there is still important foundation work to be done. It is generally believed that constipation increases with disease progression but in this study we demonstrated that constipation seems to be stable overtime, we do see increases in constipation scores but these are best explained by other factors such as medication and lack of exercise, rather than disease severity. These findings have important implications for clinical management of people with gut problems but also for how we recruit people to studies and clinical trials.
What therapies might the future hold for Parkinson's disease targeting gut health?
This study shows that not all people with Parkinson's disease will have gut issues. However, given that our previous research showed that those who experience gut issues are more likely to progress faster, it is important to address gut problems.
Targeting gut health may not only improve the quality of life for people but, importantly, it may contribute to a slower Parkinson's decline. Exciting new research on the therapeutic effects of probiotics, faecal microbiota transplants and biofeedback, among others, is promising but more groundwork is needed to understand the gut function in Parkinson's disease.
How did patients feel about participating in a gut health Parkinson’s study?
Many patients expressed keenness to participate as they experienced gut problems and felt that participating in our study was a way to know more about their own gut issues whilst contributing to the advancement of knowledge in the field. Many were also happy to support research that focuses on the non-motor symptoms of Parkinson’s disease, which can be as troubling as the movement issues for some patients.
What did your study look at and what was found?
We set out to characterize how gut dysfunction evolved over time in Parkinson’s disease. We recruited over 400 people with Parkinson’s, at different disease stages and followed up a subset of them for 4 years. We also recruited people at risk of developing Parkinson’s and controls. Using questionnaires and an objective measure of transit time (the ‘Blue Poop Challenge’), we showed that:
- Constipation is not a universal feature of Parkinson's disease: some patients even in advanced stages of Parkinson's do not suffer from constipation.
- Constipation does not increase with Parkinson's disease stages (after accounting for relevant confounders) and seems stable over time.
- Difficulty swallowing can be present in early stages of Parkinson's disease.
Altogether, our study suggests that constipation may be a feature of a particular subtype of Parkinson's, which holds important implications for how people are cared for in the clinic but also how researcher stratify and recruit for their studies to better understand Parkinson’s
One last question – what was the ‘Blue Poop Challenge’ mentioned above?
The Blue Poop Challenge is a measure of whole gut transit time which consists in ingesting of a blue food dye (cake baking dye), and recording the length of time, in hours, until the first appearance of blue stool. It’s particularly useful in research because it is an accessible and scalable way to measure transit time in large number of individuals and can be done in the convenience of their own home.
