Effects of a Placebo Probiotic on Gut Health and General Well-being in Individuals With Mild Gastrointestinal Symptoms

Official title

A 3-week Randomized Controlled Trial on the Efficacy of a Placebo Probiotic in Rebalancing Gut Health and Fostering Physical and Emotional Well-being in Individuals With Mild Gastrointestinal Symptoms

Overview

The present study is aimed at exploring whether positive expectations of receiving a three-week treatment with a probiotic supplement (in fact a placebo) improve symptoms of gastrointestinal distress and promote physical and emotional well-being in healthy individuals with mild gastrointestinal symptoms. At first, a comparison is planned between (1) a classic deceptive placebo manipulation (Deceptive Placebo group, DP), and (2) a control condition (Control group, C), in which no placebo substance will be administered. After the three-week waiting list, the Control group will be invited to take the placebo probiotic pills in an "open-label" fashion (Open Label Placebo, OLP). Specifically, participants will be informed that the pills are inert placebos. An exploratory analysis will help to clarify whether the OLP paradigm leads to significant effects, based on a within-group (C- OLP) and between-group comparison (DP-OLP).

Interventions

• Other Placebo probiotic
  Three-week consumption of placebo probiotic capsules passed off as being actual probiotics
• Other Open-Label Placebo probiotic
  Participants of the Control group will be switched to this condition after three weeks and receive placebo probiotic capsules for the following three-weeks of no intervention. Specifically, they will be honestly informed that the capsules are inert placebos.
• Other Control-no treatment
  For the first three weeks, the Control group will not be exposed to any intervention.

Primary outcome measures

• Change from Baseline in the Gastrointestinal Symptom Rating Scale (GSRS) total score at 3 weeks. [Time frame: Baseline and 3 weeks]

Secondary outcome measures (6)

• Change from Baseline in the Digestion-Associated Quality Of Life Questionnaire (DQLQ) total score at 3 weeks. [Time frame: Baseline and 3 weeks]
• Change from Baseline in Stool Form as assessed by means of the Bristol Stool Scale [Time frame: Day 2/3 and day 19/20 from Baseline]
• Change from Baseline in Fatigue Levels as assessed by means of the Multidimensional Fatigue Inventory (MFI-20) at 3 weeks. [Time frame: Baseline and 3 weeks]
• Change from Baseline in Sleepiness Levels as assessed by means of the The Epworth sleepiness scale at 3 weeks. [Time frame: Baseline and 3 weeks]
• Change from Baseline in Positive and Negative affect as assessed by means of the Positive and Negative Affect Schedule (PANAS) at 3 weeks. [Time frame: Baseline and 3 weeks]
• Change from Baseline in Stress Levels as assessed by means of the Perceived Stress Scale (PSS) 3 weeks. [Time frame: Baseline and 3 weeks]

Eligibility criteria

Inclusion criteria

• Age between 20 and 65
• Individuals with mild gastrointestinal symptoms (e.g., digestive issues, acid reflux, constipation) such that normal every-day activities are not severly compromised.

Exclusion criteria

• Individuals with a diagnosis of functional gastrointestinal disorders (e.g., irritable bowel syndrome, ulcerative colitis, chronic inflammatory bowel diseases).
• Individuals suffering from neurodegenerative diseases and/or psychiatric conditions
• Individuals taking probiotic supplementation at the time of enrollment in the study

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Italy · 1 center

• Catholic University of the Sacred Heart — Milan

Identifiers

NCT: NCT06720558 · PlaCIBO_MtBlab

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗