Exploring the causal relationship between gut microbiota and thromboembolism: A Mendelian randomization study.

Area of Science:

• Microbiome research
• Genetics
• Cardiovascular disease epidemiology

Background:

• Emerging evidence suggests a link between gut microbiota (GM) and thromboembolic diseases.
• The precise causal role of GM in conditions like arterial embolism and thrombosis (AET), venous thromboembolism (VTE), and pulmonary embolism (PE) remains largely undetermined.
• Investigating these associations is crucial for understanding disease mechanisms and developing novel therapeutic strategies.

Purpose of the Study:

• To investigate the potential causal associations between gut microbiota composition and the risk of three major thromboembolic conditions.
• To differentiate the impact of specific gut microbial genera on arterial embolism and thrombosis (AET), venous thromboembolism (VTE), and pulmonary embolism (PE).
• To leverage genetic data for a robust causal inference analysis.

Main Methods:

• Employed a two-sample Mendelian randomization (MR) analysis, a robust method for inferring causality.
• Utilized large-scale genome-wide association study (GWAS) datasets from MiBioGen (for GM) and FinnGen (for thromboembolic outcomes).
• Applied the inverse-variance weighted (IVW) approach, assessing heterogeneity and pleiotropy to ensure reliable results.

Main Results:

• Identified 16 gut microbial genera with significant associations with thromboembolic risks under specific analytical conditions.
• Observed distinct microbial associations for each condition: e.g., Holdemanella and Ruminococcus gnavus group protective against AET; Eubacterium rectale group linked to increased VTE risk; Erysipelatoclostridium positively associated with PE risk.
• Noted that none of the identified associations survived stringent Bonferroni correction, indicating preliminary findings.

Conclusions:

• This Mendelian randomization study provides exploratory evidence suggesting potential causal links between specific gut microbial genera and thromboembolic disorders.
• The findings highlight specific microbes that may influence the risk of AET, VTE, and PE.
• Further research and validation are essential to confirm these hypothesis-generating results and their clinical implications.