Probiotics for depression and mood problems in Parkinson's disease

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Participants with Parkinson's disease and mild-to-moderate depression are randomized in a triple-blinded, placebo-controlled design to receive either a multi-strain probiotic or placebo for 12 weeks. Eligibility includes ages 40–80, Hoehn and Yahr stage 1–3 in the ON state, and a BDI-II score of 14–28, with exclusions for recent probiotic or antibiotic use and significant cognitive impairment. Mood outcomes are measured with standard clinical scales and participants maintain their usual activity levels during the intervention. The trial is conducted at the Pacific Parkinson's Research Centre, affiliated with the University of British Columbia.

Why it matters

Who can join: the full rules

Inclusion Criteria:

1. Confirmed diagnosis of Parkinson's disease based on UK Brain Bank criteria
2. Between the ages of 40-80 years
3. Mild to Moderate PD (Hoehn and Yahr stage between 1-3 in the "ON" state)
4. Mild to moderate depression (BDI-II score of 14-28 in the "ON" state)
5. Women of childbearing potential must agree to use a medically approved method of birth control (e.g., hormonal contraceptives, intrauterine devices, vasectomy/tubal litigation, barrier methods and double barrier method) and must have negative pregnancy test results at screening and baseline
6. Willingness to maintain current physical activity levels during study period
7. English proficiency

Exclusion Criteria:

1. Atypical Parkinsonism
2. Active suicidality
3. Active psychosis
4. Cognitive score (MoCA) of \< 21 in the "ON" state
5. Severe depression (BDI-II score \> 28 in the "ON" state)
6. Probiotic, Saccharomyces boulardii and/or antibiotic use in the past 3 months (yogurt, kefir, and other probiotic-containing foods are allowed)
7. The use of natural health products that affect depression (e.g., St. John's Wort, passion flower, gaba, 5-htp, kava, bacopa, efa's)
8. Change in the schedule of concurrent psychotherapy or brain stimulation for the treatment of mood or anxiety disorders in the last 4 weeks
9. Change in antidepressant or anxiolytic medication (including benzodiazepines) within the last 4 weeks
10. Change in Parkinson's medication within the last 2 weeks
11. Neurological disease other than PD, including Alzheimer's disease, multi-infarct dementia, Huntington's disease, normal pressure hydrocephalus, a brain tumour, progressive supranuclear palsy, seizure disorder, subdural hematoma, multiple sclerosis, or history of significant head trauma
12. A significant immune-compromised condition due to either a health condition or use of an immune suppressant (e.g., AIDS, lymphoma, chemotherapy treatment, patients undergoing long-term systemic corticosteroid or immunosuppressant treatment)
13. A known bleeding disorder
14. Current illness (e.g., a cold or flu-like symptoms) and infections (e.g., hepatitis, HIV, gastroenteritis, fungal, or parasitic infections)
15. Allergy to corn starch or corn
16. Concurrent treatment for Parkinson's disease with Duodopa
17. Change in Deep Brain Stimulation (DBS) stimulation parameters in the last 4 weeks
18. New onset of significant psychiatric symptoms following DBS procedure that are considered likely related
19. Women who are pregnant, breastfeeding, or planning to become pregnant during the course of the trial
20. Unstable medical conditions or serious disease/conditions (e.g., cancer undergoing active treatment, poorly controlled diabetes)
21. Drug and/or substance abuse
22. The patient, in the opinion of the Investigator, is unable to adhere to the requirements of the study. This includes any patient who, in the judgment of the Investigator, is likely to be noncompliant during the study, or unable to cooperate because of a significant language barrier or cognitive impairment

Where it's running

• Pacific Parkinson's Research Centre
  Vancouver, British Columbia, Canada Recruiting

Study contacts

• Study coordinator: Matthew Leung, BSc
• Email: Matthew.Leung@ubc.ca
• Phone: 604-827-1905

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

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• Psilocybin therapy for treating depression in Parkinson's disease

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.