Objectives: Approximately 20% of patients with abdominal aortic aneurysm (AAA) have diabetes mellitus (DM). The diagnosis of DM in patients with a small AAA has been associated with an over 20% reduction in the growth of the AAA maximal transverse diameter (MTD) that has been attributed to less active aortic matrix degeneration. After exclusion of AAAs with endografts, it is not known whether DM is associated with an alteration in the behavior of the residual sac. We hypothesized that patients with DM will demonstrate greater regression of the sac after endovascular AAA repair. We also evaluated the association of DM with presence of late type II endoleak (T2E).
Methods: We performed a retrospective analysis from the national Vascular Quality Initiative endovascular AAA repair (EVAR) module from 2003 to 2022 in patients with recorded baseline MTD and at least one long-term follow up (LTFU) after 180 days with recorded MTD. Patients were excluded from analysis: unknown diabetes diagnosis; unknown aspirin, P2Y12 inhibitor, or statin use; prior AAA intervention; known genetic aneurysm predisposition; open conversion; and reintervention before 180 days. Multivariate linear regressions were performed in R (version 4.2.2) for diameter analysis, adjusted for baseline MTD and other covariates listed in Table II. Multivariate logistic regressions were performed for T2E outcome, with covariates as in Table II. Cluster analysis and redundancy analysis were performed to examine the correlation structure among the study variables and missing data pattern. Multiple imputation was performed to impute missing covariate data before fitting multivariable models.
Results: 29,075 patients met our inclusion criteria. 5,745 had DM. Descriptive statistics are summarized (Table I). Overall, MTD shrunk, with a Wilcoxon signed-rank test showing a median change of -5mm, and mean change of -6.1mm, with a < 0.001 p-value. On univariate analysis adjusted for baseline MTD, diabetes was significantly associated with diameter at follow up analysis (coefficient 1.058, 95%CI(0.796,1.321), p< 0.001). On multivariate analysis, diabetes was found to be significantly related to decreased sac regression (coefficient 0.601, 95%CI(0.335,0.866), p< 0.001) (Table II). There was no significant association between diabetes and T2E at follow up on multivariate analysis (OR 0.667, 95%CI(0.373,1.193), p=0.172).
Conclusions: Diagnosis of DM was significantly associated with slower or absent sac regression after EVAR, which does not directly support our hypothesis that DM inhibits the degenerative process of AAA. Patients with DM were not found to have a difference in T2E after EVAR.
.jpg "Lena Leszinsky, BA (she/her/hers) photo")