Probiotics as an add-on treatment for Parkinson’s disease patients suffering from motor fluctuations and dysbiosis

Abstract

Background: Parkinson’s disease is the second most common neurodegenerative disease in our setting. It is characterised by the onset of motor symptoms, but patients present with a wide range of non-motor symptoms. Gastrointestinal symptoms are very common, constipation and delayed gastric emptying are common complaints of patients because of an early impairment of the enteric nervous system. In addition, many studies have demonstrated the presence of gut dysbiosis in PD patients, although it is not yet known whether it is a cause or a consequence. Regardless, PD patients often develop a condition known as small intestine bacterial overgrowth. This has been shown to be one of the causes of motor fluctuations in levodopa-treated PD patients; and its treatment improved them. However, because predisposing factors were still present, relapse rates were substantially high. Recently, there has been increased interest in the benefits of using probiotics in PD patients to treat these gastrointestinal complaints. By restoring the gut microbiota, patients regain normal gut function. In preclinical and clinical studies, probiotics have been shown to improve both motor and non-motor scales and overall quality of life in PD. Objective: the main objective of this clinical trial is to demonstrate that the use of probiotics as a post-treatment of antibiotics (rifaximin) in PD patients suffering from small intestine bacterial overgrowth and motor fluctuations reduces the relapse rate and provides an improvement in levodopa efficacy, compared to patients receiving placebo alone after standard treatment.

Design: this will be a multicentre, randomized, double-blind, placebo-controlled, parallel- group study in all Catalan hospitals with a motor disorders department.

Intervention and Methods: subjects of the study will be patients with Parkinson’s disease suffering from motor fluctuations and small intestine bacterial overgrowth. Our sample size will be of 432 patients. All of them will be treated with antibiotics, and after they will be randomized in two groups: intervention group (n=216), in which patients will be taking probiotics; and placebo group (n=216). the intervention group (taking probiotics) and 216 in the control group (taking placebo)