Anatomical pathways mediating the effect of diabetes on the abdominal aorta: a chain-of-mediation model

Background: Diabetes mellitus (DM) increases cardiovascular risk, possibly through structural changes in the abdominal aorta mediated by specific aortic segments. Objective: To analyze how DM influences abdominal aortic diameter through thoracoabdominal aortic segments. Method: Cross-sectional study using secondary data (n = 801) from patients evaluated by non-contrast chest CT. The relationship between DM (independent variable) and abdominal aortic diameter (dependent variable) was analyzed, considering six anatomical aortic segments as mediators. PROCESS macro model 6 by Hayes was applied using linear regression and bootstrap resampling (5,000 samples). A directed acyclic graph was created to theoretically support the model. results: There was no direct effect of DM on abdominal aortic diameter (β = –0.0199; 95% CI: –0.2694 to 0.2296), but the total indirect effect was statistically significant (β = 0.1268; 95% CI: 0.0898 to 0.1636). The strongest mediating effect was through the mid-descending aorta (β = 0.1539; 95% CI: 0.0779 to 0.2468). conclusion: DM significantly affects abdominal aortic diameter through specific mediating pathways involving various aortic segments.