THURSDAY, July 23, 2026 (HealthDay News) -- For adults with chronic insomnia disorder, a fecal microbiota transplantation (FMT)-based treatment protocol is associated with improved sleep continuity, according to a study published online July 22 in the Journal of Internal Medicine.
Teng Gao, from the Peking University Institute of Mental Health in Beijing, and colleagues conducted a multicenter, randomized, double-blind, placebo-controlled trial to examine whether an FMT-based treatment protocol improves sleep outcomes in adults with chronic insomnia disorder. Participants were randomly assigned to receive short-course antibiotic pretreatment followed by donor microbiota capsules or placebo capsules without antibiotic pretreatment (40 each). For prespecified exploratory subgroup analyses, participants were further randomly assigned within each group to receive synbiotic supplementation or matched placebo.
The researchers found that the FMT-based treatment protocol improved sleep efficiency (SE) compared with placebo (adjusted between-group difference, 13.9 percentage points) and reduced wake after sleep onset. There were no meaningful differences in SE in association with synbiotic assignment. From two to six months, there was sustained improvement in the Insomnia Severity Index and Pittsburgh Sleep Quality Index scores. Treatment was well tolerated; there were mild, self-limited adverse events and no serious adverse events. Microbial richness and diversity were increased, and community structure was altered with the intervention; posttreatment β-diversity change was similar in responders and nonresponders, but they had different baseline microbiota composition.
"Targeting the gut microbiota may offer a promising new therapeutic strategy for chronic insomnia disorder," coauthor Yanping Bao, Ph.D., also from Peking University, said in a statement. "This work also strengthens our understanding of the gut-brain axis as an important regulator of human sleep."
