In a cross-sectional study of adults with long-standing type 1 diabetes, integrative oral and gut metagenomic profiling identified distinct microbial signatures associated with microvascular and macrovascular complications compared with complication-free patients and healthy controls. A core panel of 26 gut and 8 oral species correlated with complication status; notably, butyrate-producing taxa such as Blautia wexlerae, Anaerobutyricum hallii, Roseburia inulinivorans , and A. soehngenii , along with specific oral Neisseria species, were enriched in those without complications, suggesting a protective microbial milieu.
Mediation analyses indicated that select microbes partly link glycemic control and insulin resistance measures to complication risk, and models combining oral and gut features outperformed single-site models for classifying patients with complications. These findings point…
