Do probiotics improve vagal function in depression?
In an RCT of 43 depressed patients and 43 controls, three months of a multi-species probiotic lowered morning heart rate and raised morning RMSSD/lnHF in depression versus placebo, with more Akkermansia and better sleep metrics.
Source
Multi-species probiotic supplement enhances vagal nerve function - results of a randomized controlled trial in patients with depression and healthy controls
Study at a glance
- Design
- RCT — Randomized placebo-controlled trial of OMNi-BiOTiC STRESS Repair twice daily in MD vs healthy controls; 24-h HRV, stool 16S, sleep; NCT-04772664
- N
- N=86 · 43 major-depression patients and 43 healthy controls randomized to probiotic or placebo; 148 screened
- Population
- Adults 18–65 with ICD-10 major depression (on usual care) and healthy controls
- Outcome
- Vagus nerve function by 24-h HRV (morning RMSSD/lnHF/heart rate), microbiome, and sleep
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
Randomized MD and healthy adults to OMNi-BiOTiC STRESS Repair or placebo twice daily, collecting 24-h ECG/HRV, stool 16S, serum, and questionnaires at baseline, 7 days, 28 days, and 3 months (NCT-04772664).
What they found
MD had higher heart rate and lower 24-h pNN50/RMSSD/SDNN than controls. After 3 months, MD on probiotic vs placebo had lower morning heart rate (t(33)=3.23, p=.003, d=1.10) and higher morning RMSSD (p=.002) and lnHF (p=.001), plus more Christensenellales/Akkermansia and improved PSQI sleep latency/medication use.
The limits
What it doesn't show
Adjunctive probiotics are not a stand-alone antidepressant trial; sample is modest, MD stayed on usual psychotropics, and abstract ‘vs HC’ wording is looser than the placebo-contrast results.
Key terms
- Vagus nerve (VN) / HRV
- Cardiac autonomic markers (RMSSD, pNN50, lnHF, RSA) used here as a proxy of vagal function.
- Multi-species probiotic
- OMNi-BiOTiC STRESS Repair given twice daily versus placebo.
- RMSSD
- Root mean square of successive R-R differences; higher values indicate greater vagal modulation.
- Akkermansia muciniphila
- Mucin-degrading gut microbe that increased in MD participants on probiotic.
- NCT-04772664
- ClinicalTrials.gov registration for this Graz RCT.
Flashcards
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
Enrollment was about:
Common questions
Who was enrolled?
43 MD patients and 43 healthy controls (148 screened).
What was the primary endpoint?
Change in vagus function assessed by HRV.
What happened to morning HR in MD at 3 months?
Lower on probiotic than placebo (p=.003, d=1.10).
Which microbe increased?
Christensenellales, particularly Akkermansia muciniphila.
More on Psychiatric neuroimaging