B0634 - Effect of Probiotics on Mental Health and Their Association With Serum Neurometabolites in Adults With Depression or Anxiety: A Systematic Review and Meta-Analysis
Introduction: Tryptophan metabolism is implicated in the development of mental illnesses such as depression and anxiety. Breakdown of the essential amino acid tryptophan produces neurometabolites (namely kynurenine and serotonin) through the classic kynurenine pathway, the neurochemical pathway, and the microbiome-derived metabolic pathway in the gut. Probiotics targeting the gut can regulate the production of these neurometabolites and offer affordable supplements for managing mental illnesses. The objective is to conduct a systematic review and assess the effectiveness of probiotic intake in altering the kynurenine:tryptophan ratio (K:T ratio), serum neurometabolites, and symptoms of depression and anxiety in adults.
Methods: We conducted literature searches via PubMed, SCOPUS, Cochrane (Reviews and Trials), CINAHL, ClinicalTrials.gov and PsycINFO from inception to 2022. We included randomized controlled trials that assessed the impact of probiotics on serum neurometabolites and depression or anxiety scores versus placebo in adults with at least 4 weeks of follow-up. The Cochrane Risk of Bias Tool 2.0 was used to assess the methodological quality of studies. Forest plots were generated for outcomes that had sufficient trials.
Results: We identified a total of 851 studies and four studies were included in the meta-analysis. Three studies assessed the impact of probiotics on depression and showed significant improvement in symptom reporting scores (standardized mean difference [SMD] = -0.49; I2 = 0%; CI = -0.80 to -0.19). Three studies assessed change in anxiety scores with probiotic intervention (SMD= -0.47; I2 = 0%, 95% CI = -0.80 to -0.14). Three studies assessed the effect of probiotics on kynurenine and showed a significant reduction (SMD = -0.41; I2 = 0%, 95% CI = -0.72 to -0.10). Three studies assessed the effect of probiotics on tryptophan (SMD = -0.19; I2 = 74%, 95% CI = -0.81 to 0.42). Results for K:T ratio and changes in serum serotonin levels are forthcoming.
Discussion: Overall, probiotics significantly improved depression and anxiety symptoms and reduced kynurenine levels in adults. However, there was no significant change in serum tryptophan levels. Few studies reported data that could be included in this meta-analysis. More research is needed to assess the impact of probiotic intake on gut neurometabolic metabolism. This systematic review has important implications for further studying the relationship between the gut and mental health.
Disclosures:
Shefali Gladson indicated no relevant financial relationships.
Htun Ja Mai indicated no relevant financial relationships.
Laila Akallal indicated no relevant financial relationships.
Emerson Frizzell indicated no relevant financial relationships.
Renata Yen indicated no relevant financial relationships.
Rebecca Emeny indicated no relevant financial relationships.
Shefali Gladson, MD, MPH1, Htun Ja Mai, MBBS, MPH1, Laila Akallal, MPH2, Emerson Frizzell, BS3, Renata W. Yen, MPH1, Rebecca Emeny, PhD, MPH1. B0634 - Effect of Probiotics on Mental Health and Their Association With Serum Neurometabolites in Adults With Depression or Anxiety: A Systematic Review and Meta-Analysis, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.
