Article Text
Abstract
Background Insomnia is a common sleep disorder in the general population that suffers from difficulties in initiating or maintaining sleep. Generally, insomniacs suffer from psychiatric disorders like depression and anxiety being the most common. Research has shown that probiotic supplementation can enhance sleep quality or relieve stress in recent years. Therefore, this study assesses and sheds light on the potential sleep-improving effect of probiotics in alleviating insomnia by modulating intestinal microbiota composition.
Methods Based on the PRISMA guidelines, several databases (PubMed, Web of Science, OVID Medline) were accessed to perform systematic literature searches using ‘Insomnia’ OR ‘Sleep disorder’ AND ‘Probiotics’ as the MeSH terms. Studies investigating the use of probiotics in the management of insomnia or symptoms related to sleeping disorders were included. Along with reviews, conference proceedings and commentaries, studies without the probiotic intervention were excluded.
Results Out of 567 articles, nineteen studies conform to the inclusion criteria were selected for qualitative analysis. Five of the 19 studies were animal studies demonstrating probiotic interventions have sleep-improving effects in different rodent models (caffeine-induced sleep disturbance and pentobarbital-induced sleep models). The remaining 14 are human trials, including two open-label studies. Seven out of 12 randomised, double-blind, placebo-controlled trials showed positive outcomes of probiotic interventions in improving the sleep quality of insomniacs, in terms of reduced Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) scores, while placebo effect or no significant improvement in sleep quality was reported by the other 5 of the trials. Furthermore, several studies, including both human and animal studies, demonstrated that oral administration of probiotics (Lactobacillus and Bifidobacterium) could restore a balanced gut microbiota composition from dysbiosis associated with stress and psychological condition (IDDF2022-ABS-0241 Figure 1. The oral administration of probiotics could restore a balanced gut microbiota composition from dysbiosis associated with stress and psychological condition).
Conclusions This study showcased the sleep-improving effect of probiotic interventions as an alternative therapy for insomnia. A considerable amount of human studies demonstrate that probiotics could be promising therapeutic options for patients suffering insomnia related to psychological stress. Nonetheless, future studies should clarify the exact mechanism and confirm the beneficial effects of various probiotics on sleep while considering the treatment durations, dosage and different probiotic strains combination.