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Probiotics and the Gut Brain Axis- Do Probiotics Interact With the Vagal Nerve?

Not Applicable
Completed
Conditions
Depressive Disorder, Major
Interventions
Dietary Supplement: Multispecies-Probiotic
Dietary Supplement: Placebo Supplement
Registration Number
NCT04772664
Lead Sponsor
Medical University of Graz
Brief Summary

The purpose of this study is to investigate the effects of a multispecies probiotic on the function of the vagal nerve in patients with major depression and healthy participants in a single-center, randomized, placebo-controlled trial.

Detailed Description

After being informed about the study and potential risks, all participants giving written informed consent will be screened for eligibility for study entry and will be randomized in a double-blind manner to receive either a multistrain probiotic or a placebo for 3 months. At entry, 1 week after inclusion, 4 weeks after inclusion and 3 months (end of study) vagal activity will be measured using a 24hr electrocardiogram.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
86
Inclusion Criteria
  • informed consenct
  • confirmed diagnosis of depression according to ICD-10 or DSM-V
  • age between 18 and 65 years
Exclusion Criteria
  • Suicidality
  • no informed consent or no ability to provide consent
  • cardiovascular disease
  • pregnancy, breastfeeding
  • alcohol or drug dependency
  • other severe psychiatric or organic conditions (epilepsy, brain tumor, recent surgery)
  • malignant diseases
  • dementia (MMST<20)
  • severe autoimmune-disorder or immunosuppression (systemic lupus, HIV, multiple sclerosis)
  • antibiotic therapy in the last month
  • misuse of laxative
  • acute infections
  • diarrhoea
  • gastrointestinal surgeries (except appendectomy)
  • no probiotic intake in the last 6 months
  • no regular intake of other supplements, probiotics or antibiotics during the study

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Participants with Major Depression receiving a multi-strain probioticMultispecies-ProbioticParticipants with Major Depression receiving a multi-strain probiotic
Healthy volunteers receiving a placeboPlacebo SupplementHealthy volunteers receiving a placebo
Healthy volunteers receiving a multi-strain probioticMultispecies-ProbioticHealthy volunteers receiving a multi-strain probiotic
Participants mit Major Depression receiving a placeboPlacebo SupplementParticipants mit Major Depression receiving a placebo
Primary Outcome Measures
NameTimeMethod
Change of Vagal function4 measurements with 24-hr heart rate variability at study entry, one week after, 1 month after and after 3 months

Heart rate variability parameters (logRSA; SDNN)

Secondary Outcome Measures
NameTimeMethod
Change in Hamilton Scale for Depression (HAMD)4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

Scoring is based on the 17-item scale and scores of 0-7 are considered as being normal, 8-16 suggest mild depression, 17-23 moderate depression and scores over 24 are indicative of severe depression

Change in Pittsburgh Sleep Quality Inventory (PSQI)at study entry, after 7 days, after 4 weeks and after 3 months

The PSQI is used to rate sleep quality. It includes a scoring key for calculating a patient's seven subscores, each of which can range from 0 to 3. The subscores are tallied, yielding a "global" score that can range from 0 to 21. A global score of 5 or more indicates poor sleep quality; the higher the score, the worse the quality.

Change of Interleukine-6 (IL-6)4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

IL-6 is measured from serum samples with a Cobas analyzer.

Change of Gut microbiome analysis4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

16S sequencing of gut microbiome samples, gut microbiota composition will be investigated with QIIME2 and characterized in terms of diversity (alpha-diversity, beta diversity) and differential bacterial abundance between time points.

Mini-international neuropsychiatric interview (M.I.N.I.)at study entry

short structured clinical interview which enables researchers to make diagnoses of psychiatric disorders according to DSM-IV or ICD-10

Change in Adult Attachment Scaleat study entry, after 7 days, after 4 weeks and after 3 months

The scale consists of 18 items scored on a 5 point likert-type scale. It measures adult attachment styles named "Secure", "Anxious" and "Avoidant", defined as:

* Secure = high scores on Close and Depend subscales, low score on Anxiety subscale

* Anxious = high score on Anxiety subscale, moderate scores on Close and Depend subscales

* Avoidant = low scores on Close, Depend, and Anxiety subscales

Change in "Wiener Ernährungsprotokoll"at study entry, after 7 days, after 4 weeks and after 3 months

24-hr food recall

Change of Oxytocin4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

Oxytocin will be measured from serum samples using ELISA

Change of C-reactive protein (CRP)4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

CRP is measured from serum samples with a Cobas analyzer.

Change of Body mass index4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

Weight will be measured with a calibrated scale, height will be measured with a non expandable tape. BMI will be calculated using the formula \[kg/m2\].

Change in International Physical Activity Questionnaireat study entry, after 7 days, after 4 weeks and after 3 months

The IPAQ is a 27-item self-reported measure of physical activity for use with individual adult patients. There are no validated cut-offs.

Beck Depression Inventory (BDI)Change in 4 time points at study entry, one week after, 1 month after and 3 months (completion of the study)

21-question multiple-choice self-report inventory, one of the most widely used psychometric tests for measuring the severity of depression. The rating is as follows: 0-13: minimal depression 14-19: mild depression 20-28: moderate depression 29-63: severe depression

Trial Locations

Locations (1)

Medical University of Graz

🇦🇹

Graz, Styria, Austria

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