Potential causal association between gut microbiome and posttraumatic stress disorder

Area of Science:

• Neuroscience
• Microbiology
• Genetics

Background:

• The relationship between the gut microbiome and posttraumatic stress disorder (PTSD) remains unclear.
• Investigating potential causal links is crucial for understanding PTSD pathophysiology.

Purpose of the Study:

• To clarify the potential causal association between gut microbiome features and PTSD development.
• To utilize Mendelian randomization (MR) for assessing these causal effects.

Main Methods:

• Genome-wide association study (GWAS) summary statistics from the MiBioGen consortium for gut microbiome data.
• Utilized Freeze 2 and FinnGen datasets for PTSD, employing the Psychiatric Genomics Consortium Posttraumatic Stress Disorder Working Group (PGC-PTSD).
• Applied inverse variance weighting (IVW) as the primary MR method, with sensitivity analyses for pleiotropy and heterogeneity; reverse MR was also performed.

Main Results:

• Eight bacterial traits showed a potential causal link to PTSD in the PGC-PTSD Freeze 2 datasets (P < 0.05).
• Genus.Dorea and genus.Sellimonas associations were replicated in FinnGen datasets.
• Sensitivity analyses confirmed the robustness and reliability of the findings, supporting the IVW results.

Conclusions:

• The study suggests a potential causal impact of the gut microbiome on PTSD development.
• Findings highlight the role of the gut-brain axis in PTSD and warrant further investigation into mechanisms.
• Novel evidence is provided, calling for confirmation studies and exploration of underlying biological pathways.