Gut microbiota on sleep disorders throughout the lifespan

The gut microbiota undergoes dynamic changes and plays a crucial role in human health and disease throughout life. Studies have revealed gut microbiota disruption in various microbiota‑gut‑brain axis‑related diseases at different life stages, transcending boundaries of traditional medical disciplines. This article reviews the literature on gut microbiota and sleep disorders throughout the human life cycle, encompassing obstructive sleep apnea, circadian rhythm sleep disorders, and insomnia. Gut microbiota dysbiosis has been implicated in sleep disorders comorbid with neurodevelopmental diseases in children, psychiatric and gastrointestinal diseases in adults, and neurodegenerative and cardiovascular diseases in the elderly. The mechanisms by which gut microbiota regulates sleep through the immune, neuronal, and endocrine pathways are explored. The therapeutic potential of microbiota‑based interventions for sleep disorders is investigated, with particular emphasis on clinical evidence and controversies regarding probiotics and fecal microbiota transplantation (FMT) at each critical life stage. The quality of clinical studies on FMT and probiotics for sleep disorders is assessed according to the latest guidelines of the preferred reporting items for microbiotherapy (PRIM). Of the 106 included studies, according to PRIM criteria, 40.0% (6/15) of FMT studies and 57.1% (52/91) of probiotic studies were classified as low‑quality research (defined as PRIM score < 14). This review provides future directions to facilitate the development of microbiota‑based research and therapeutic strategies for sleep disorders. A comprehensive understanding of the microbiota‑gut‑brain axis in sleep disorders across life stages holds transformative potential for the development of personalized therapies.