The beneficial effect of a multispecies probiotic intervention on quality of sleep - a randomized, double-blinded, placebo-controlled study.

Probiotic intervention improved quality of sleep beyond an observable placebo effect as measured by PSQI score.

• Final PSQI scores were 6.8 ± 2.9 in the probiotic group versus 7.7 ± 3.1 in the placebo group (p = 0.036)
• Baseline PSQI scores were similar between groups: 10.1 ± 2.7 (probiotic) vs. 10.5 ± 2.6 (placebo)
• Both groups showed improvement from baseline, but the probiotic group showed greater improvement
• Participants were required to have self-reported impaired quality of sleep defined as PSQI > 5 at enrollment

The probiotic intervention specifically improved sleep efficiency and sleep latency.

• Improvements in sleep efficiency and latency contributed to the overall improvement in quality of sleep
• The intervention was 28 days in duration using OMNiBiOTiC® STRESS Repair, a multispecies probiotic
• The study design was randomized, double-blind, and placebo-controlled

Ninety-four of 130 randomized participants completed the study and were included in the analysis.

• Participants were randomized 1:1 to probiotic (n = 50) or placebo (n = 44) groups at study completion
• The probiotic group was 88.6% female with a mean age of 41.2 ± 10.6 years
• The placebo group was 88.0% female with a mean age of 40.1 ± 10.7 years
• Baseline characteristics were similar between groups

Probiotic bacteria were partially recovered in stool microbiome samples, causing a slight shift in beta diversity in the probiotic group.

• Stool samples were collected before and after the intervention for 16S rRNA sequencing
• Beta diversity shifted slightly in the probiotic group following intervention
• The recovery of probiotic bacteria in the microbiome was only partial, not complete

The probiotic intervention did not influence quality of life or perceived stress.

• Validated questionnaires were used to estimate quality of life and perceived stress in addition to sleep quality
• No significant differences between probiotic and placebo groups were found for quality of life or perceived stress outcomes
• The study assessed these secondary outcomes alongside the primary sleep quality outcome