Investigating bidirectional causal relationships between gut microbiota and insomnia

Area of Science:

• Microbiome research
• Sleep science
• Genetics

Background:

• The gut microbiota's influence on sleep is increasingly studied, but its specific interaction with insomnia remains unclear.
• Existing research highlights potential links between gut bacteria and sleep patterns.

Purpose of the Study:

• To investigate the bidirectional relationship between gut microbiota composition and insomnia.
• To identify specific gut bacterial taxa associated with insomnia risk and protection.

Main Methods:

• Mendelian randomization (MR) analysis using large genome-wide association studies datasets for insomnia and gut microbiota.
• Utilized inverse variance weighted (IVW) as the primary method, with MR-Egger, MR-PRESSO, and leave-one-out analyses to assess heterogeneity and pleiotropy.
• Steiger test was employed to confirm causal relationships.

Main Results:

• Identified 14 gut bacterial taxa potentially increasing insomnia risk (OR: 1.01-1.04) and 8 taxa showing a protective effect (OR: 0.97-0.99).
• Reverse MR analysis indicated insomnia causally affects bacterial abundance, decreasing 7 taxa and increasing 12 taxa.
• The genus *Odoribacter* demonstrated a significant positive causal link with insomnia.

Conclusions:

• Established reciprocal relationships between gut microbiota and insomnia.
• Findings offer novel insights for potential prevention and treatment strategies for insomnia targeting the gut microbiome.