Gut microbiota-derived TMAO and atrial fibrillation: meta-analysis
Elevated circulating TMAO levels are significantly associated with atrial fibrillation risk, with a pooled OR of 1.35 (95% CI 1.15–1.59).
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What the study showed
The meta-analysis of 8 odds ratio studies identified a significant positive association between circulating TMAO and atrial fibrillation. Substantial heterogeneity was present (I² = 68.3%), reflecting meaningful variability across included studies. Subgroup analysis indicated a particularly strong association in the context of postoperative AF following cardiac surgery.
How it was done
Systematic review with searches across PubMed, Web of Science, EMBASE, Scopus, and ProQuest up to April 2026, including studies reporting quantitative TMAO–AF associations. Random-effects meta-analytic pooling of ORs and HRs; publication bias assessed via Galbraith plots, Baujat plots, and Egger's test.
Risk of bias
Substantial heterogeneity (I² = 68.3%) constrains interpretation of the pooled effect. Only 9 of 15 studies contributed to quantitative synthesis; the abstract does not detail sample sizes, TMAO assay methods, or degree of confounder adjustment.
What this study does NOT prove
This study does not prove that TMAO causes atrial fibrillation, nor that dietary or microbiota-targeted interventions reducing TMAO will lower AF incidence or recurrence.
In clinical practice
The association is statistically significant, but high heterogeneity prevents direct translation to individual clinical decision-making. TMAO should not be adopted as a clinical AF risk marker without additional causal evidence.
Limitations
Substantial heterogeneity (I² = 68.3%) constrains interpretation of the pooled effect. Only 9 of 15 studies contributed to quantitative synthesis; the abstract does not detail sample sizes, TMAO assay methods, or degree of confounder adjustment.
Technical appendix
Version history
- 1.0 · 2026-09-09 — Auto-generated under Evidence Standard v1.0
Paid access: structured summary from public metadata; consult the original study at the source.