STUDY OBJECTIVES: Sleep disorders are common and impair performance and health. The intestinal microbiome regulates human chronobiology. Microbiome modulation through probiotic intervention might therefore harbor the potential to treat sleep disorders. We tested this hypothesis in a randomized, double-blind, placebo-controlled study.
METHODS: We randomized 130 volunteers with self-reported impaired quality of sleep (PSQI>5) in a 1:1 ratio to a 28-day intervention with either a multispecies probiotic (OMNiBiOTiC® STRESS Repair) or a placebo. Participants completed validated questionnaires to estimate quality of sleep, quality of life and perceived stress, and collected stool samples for 16S rRNA sequencing before and after the intervention. Ninety-four participants finished the study and were included in the analysis.
RESULTS: Baseline characteristics were similar between the probiotic group (n = 50; 88.6 % female, 41.2 ± 10.6 years old) and the placebo group (n = 44; 88.0 % female, 40.1 ± 10.7 years old), including the initial PSQI score (10.1 ± 2.7 vs. 10.5 ± 2.6). The probiotic intervention led to an improved sleep efficiency and latency, and thereby improved quality of sleep beyond an observable placebo effect (6.8 ± 2.9 vs. 7.7 ± 3.1; p = 0.036, probiotic and placebo group, respectively). Probiotic bacteria were partially recovered in the microbiome, causing a slight shift in beta diversity in the probiotic group. The intervention did not influence quality of life or perceived stress.
CONCLUSIONS: In conclusion, this well-powered RCT shows that the intervention with a multispecies probiotic improved quality of sleep beyond the effect of a placebo intervention, and that the modulation of the microbiome may therefore be of clinical benefit in alleviating sleep disturbances.