Causal association between oral microbiome and chronic kidney disease: two-sample Mendelian randomization

Chronic kidney disease (CKD) contributes to 1.2 million deaths annually. Oral dysbiosis may influence CKD, highlighting the need for further research on its role as a risk factor and preventive target.

We obtained summary statistics for genome-wide association studies (GWAS) of the oral microbiome from the GWAS Catalog and CKD from the CKDGen Consortium. Inverse variance weighting (IVW) was used as the principal analysis method, supplemented by MR-Egger, weighted median, and weighted mode to assess causal relationships. Sensitivity analyses, including MR-PRESSO and Cochran's Q, validated the robustness of the results.

The IVW results showed that Veillonella species was causally associated with CKD (OR = 0.96, 95% CI (0.93-0.99)), Order Fusobacteriales (OR = 1.01, 95% CI (1-1.01)) and Rothia species (OR = 0.99, 95% CI (0.99-1)) were causally associated with urinary albumin-to-creatinine ratio (UACR); Order Bacteroidales (OR = 0.97, 95% CI (0.94-1)) and Species micronuciformis (OR = 0.95, 95% CI (0.91-0.99)) were causally associated with CKDi25; and Streptococcus species was causally associated with dialysis (OR = 0.82, 95% CI (0.69-0.97)). There was no significant causal association between other oral microbiome features and CKD at the genetic level. Sensitivity analysis indicated that the results were robust.

Our study suggests that there are associations between the oral microbiome and CKD. To better understand its mechanism of action and to develop broader strategies for preventing chronic kidney disease, further research is required.