IDDF2024-ABS-0300 Probiotics improve insomnia by regulating gut microbiota composition

<h3>Background</h3> Insomnia is a sleep disorder characterized by difficulty falling asleep or staying asleep. Insomnia affects around 10-30% of the global population and is frequently associated with psychiatric disorders such as depression and anxiety. Insomnia can seriously affect daily functioning by causing inattention and drowsiness. It can also result in major long-term health conditions including diabetes, obesity, cardiovascular disease, and hypertension. However, effective interventions or therapeutic strategies are still lacking. Insomnia has been linked to the gut microbiome. Probiotics have been shown to relieve anxiety and stress by maintaining intestinal homeostasis. This systematic review aims to investigate the potential effects of probiotics in improving insomnia by altering the gut microbiota composition. <h3>Methods</h3> The systematic literature search was performed based on PRISMA guidelines along with relevant MeSH terms, (‘probiotics’) AND (‘chronic insomnia’ or ‘sleep disorder’) in three databases (PubMed, ProQuest, and Scopus) until April 30, 2024. The titles and abstracts of all retrieved studies were evaluated using the inclusion and exclusion criteria. Studies on gut microbiome and insomnia in clinical trials were considered for inclusion. We excluded preclinical studies with animal models reporting the effects of probiotics on insomnia. Exclusion criteria are unrelated, duplicated, unavailable full texts, case reports, and systematic review studies. <h3>Results</h3> Four studies were eligible for final quantitative analysis, with 300 anxious participants. Research findings have shown that anxious/stressed participants have a significantly lower abundance of Actinobacteria (<i>Bifidobacterium</i>), Bacteroides (<i>Prevotella</i>), and a higher abundance of Bacteroidetes, Firmicutes (<i>Roseburia, Streptococcus, Veillonella</i>), and <i>Enterobacteriaceae</i>. Consumption of probiotics significantly improved sleep quality, as evidenced by lower scores on the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) from insomniacs compared to controls. Furthermore, probiotics restored the anxiety/stress-induced alterations in gut microbiota composition by mitigating the reduction of <i>Bifidobacterium</i> and <i>Prevotella</i> while preventing the increased abundance of <i>Bacteroides, Roseburia, Streptococcus, Veillonella, and Enterobacteriaceae</i>. <h3>Conclusions</h3> This outcome highlights the potential of probiotics as an effective intervention to improve the mental health, sleep quality, and gut microbiota of people under anxious conditions by reverting the trend of change in the gut microbiome to normal conditions (IDDF2024-ABS-0300 Figure 1).