Diabetes affects approximately 70% of patients with chronic limb-threatening ischemia (CLTI) and is associated with more severe presentation, driven mostly by higher rates of wounds and infections, according to a recently presented retrospective analysis of BEST-CLI randomized controlled trial data. Investigators further found that CLTI patients without diabetes presented with more severe ischemia, were more likely to undergo major reinterventions, and that the trial’s seminal finding endures: bypass outperformed endovascular intervention when a single-segment great saphenous vein (SSGSV) graft was used as a conduit.
The data were presented during the 2024 annual meeting of the New England Society for Vascular Surgery (NESVS) in Portland, Maine (Oct. 25–27) by Cassius Iyad Ochoa Chaar, MD, associate professor at Yale School of Medicine in New Haven, Connecticut, on behalf of the BEST-CLI trial investigators.
Of note among baseline characteristics in the cohort of 1,777 patients, those with diabetes were more likely to be younger and significantly more likely to be Hispanic (17.1% vs. 4.7%), Chaar noted. Meanwhile, diabetes patients were more likely to have cardiovascular comorbidities such as hypertension, hyperlipidemia and coronary artery disease (CAD), but those without diabetes were more likely to be smokers and to have chronic obstructive pulmonary disease (COPD). Chaar also pointed out how diabetes patients had a significantly higher rate of previous minor amputation of the index limb at 18.6% vs. 6% for non-diabetes patients.
Procedurally, patients with diabetes had significantly less ischemia than those without, Chaar reported. “So, their ABIs [ankle-brachial indices] were higher—and not just ankle pressure, but their toe pressure was higher as well.” But patients with diabetes had significantly higher WIfI wound and foot infection grades, and, overall, had a higher WIfI stage compared to those without, he added. Meanwhile, there was no difference in the revascularization strategies used between the two patient groups.
In terms of the trial’s primary outcome, Kaplan-Meier analysis showed significantly higher rates of major adverse limb events (MALEs) or all-cause death (53.5% vs. 46.4%), above-ankle amputation of the index limb (17.8% vs. 9.9%), and all-cause death (34.4% vs. 26.0%) in the diabetes group at three years, Chaar revealed. “Interestingly, those curves were flipped when looking at major reinterventions: patients with diabetes had significantly decreased incidence of major reintervention [18.2% vs. 24.3%].”
Under multivariate analysis, the researchers also looked to determine whether WIfI grades compounded the impact of diabetes. “The initial regression showed that diabetes was independently associated with the primary outcome, but when you repeated the model with WIfI, that trend was still there but the significance was lost,” Chaar explained. “However, WIfI was significantly associated with the primary outcome.”
The analysis mirrors the BEST-CLI trial’s overall findings, the investigators found: that is, lower rates of major reintervention, above-ankle amputation, and MALE or all-cause death in patients who underwent bypass with SSGSV compared with endovascular procedures, irrespective of diabetes status. “Patients with diabetes had worse overall outcomes after lower extremity revascularization for CLTI, probably related to more advanced disease on presentation,” Chaar concluded.
