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Probiotics for major depressive disorder: a systematic review and meta-analysis
1Kwai Chung Hospital, Hong Kong SAR, China.
Summary
Probiotics show promise in reducing symptoms of major depressive disorder (MDD). This meta-analysis found a significant benefit of probiotics compared to placebo for patients with depression.
Area of Science:
- Psychiatry and Mental Health
- Microbiome Research
- Clinical Trials
Background:
- Major Depressive Disorder (MDD) is a prevalent and debilitating mental health condition.
- The gut microbiome's influence on mental health is an emerging area of research.
- Probiotics, live microorganisms conferring a health benefit, are being investigated for their therapeutic potential in MDD.
Purpose of the Study:
- To systematically review and meta-analyze the efficacy of probiotics in treating major depressive disorder (MDD).
- To quantify the effect of probiotics on depression symptom severity using validated rating scales.
Main Methods:
- A comprehensive search of multiple databases (MEDLINE, EMBASE, PsycINFO, Web of Science, Cochrane Library, ProQuest, Google Scholar) was conducted.
- Randomized controlled trials (RCTs) comparing probiotics to placebo in adult patients diagnosed with MDD were included.
- Standardized Mean Differences (SMDs) were calculated using random-effects models, with subgroup analyses and meta-regression exploring heterogeneity.
Main Results:
- Thirteen RCTs involving 710 patients with MDD were included in the meta-analysis.
- A pooled SMD of 0.38 indicated a statistically significant benefit of probiotics in reducing depressive symptoms.
- Moderate heterogeneity (I² = 42.8%) was observed, with no significant moderators identified in subgroup analyses or meta-regression.
Conclusions:
- Probiotics appear to be effective in reducing depressive symptoms in patients with major depressive disorder.
- Further research is needed to elucidate the factors contributing to the observed heterogeneity in treatment effects.
- The findings support the potential role of probiotics as an adjunct therapy for MDD.
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