Study of Transanal Irrigation vs Standard Care for Constipation, Gut Microbiota, and Motor Disorders in Parkinson's Disease

Constipation affects up to 80% of individuals with Parkinson's disease (PD) and frequently precedes the onset of motor symptoms. It represents one of the most burdensome non-motor manifestations of the disease, significantly impairing quality of life and increasing the need for healthcare interventions. Despite the widespread use of standard bowel care (SBC), many patients continue to experience persistent constipation, highlighting the need for more effective therapeutic strategies.

Transanal irrigation (TAI) is an established bowel management technique that has demonstrated efficacy in patients with neurogenic bowel dysfunction resulting from spinal cord injury, multiple sclerosis, and other neurological disorders. However, evidence regarding its effectiveness in patients with Parkinson's disease remains limited.

This multicenter, randomized controlled trial has been designed to compare the effectiveness of TAI using the Qufora Flow device with SBC in adults with Parkinson's disease and severe constipation. The study will evaluate whether TAI provides superior long-term bowel symptom control while also investigating its impact on patient-reported outcomes, treatment adherence, and safety.

An additional objective of the study is to explore the relationship between bowel management and gut microbiota composition. Increasing evidence suggests that alterations in the gut microbiome may contribute to the pathophysiology and progression of Parkinson's disease through the gut-brain axis. By analyzing longitudinal stool samples, the study aims to determine whether improved bowel management through TAI is associated with changes in gut microbiota and whether these changes correlate with clinical outcomes.

Participants will be followed for 24 months with standardized clinical evaluations and microbiological assessments performed according to the study protocol. The findings are expected to provide new evidence regarding the role of transanal irrigation in the management of constipation associated with Parkinson's disease and to improve understanding of the relationship between bowel function, the gut microbiome, and disease manifestations.

Inclusion criteria

• For inclusion in the study, subjects must fulfil all of the following criteria:

• Provision of informed consent.
• Female or male aged 18 years or above.
• Established diagnosis of PD according to MDS criteria
• Patients with bowel symptoms post-dating and related to a diagnosis of PD.
• PD patients suffering from constipation defined by Cleveland Clinic (Wexner) constipation score ≥10 confirmed at Baseline.
• Only TAI treatment naïve patient (not having previously used any particular TAI system).
• Judged eligible for TAI as per standardized treatment pathway .
• Able to read, write and understand information given to them regarding the study.

Exclusion criteria

Any of the following is regarded as a criterion for exclusion from the study:

• Any confirmed or suspected diagnosis of anal or colorectal stenosis, active inflammatory bowel disease, acute diverticulitis, severe diverticulosis, colorectal cancer, ischemic colitis, history of life-threatening autonomic dysreflexia, bleeding disorders, unspecified peri-anal conditions.
• Other significant neurological diseases (defined as all neurological diseases except for minor functional neurological syndromes or non-PD related neuro complications).
• Opioid consumption ≤24 hours prior enrolment.
• Taking probiotics in the past 30 days.
• Antibiotic therapy in the past 3 weeks.
• Performed endoscopic polypectomy within 4 weeks prior enrolment.
• Ongoing, confirmed pregnancy or lactation.
• Any neuromodulation that can affect the pelvic organ function.
• Current treatment of prokinetics.
• Any other condition, as judged by the investigator, might make follow-up or investigations inappropriate.

Exclusion criteria

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