Preoperative Systemic Immune-Inflammation Index Is Independently Associated with Distal Arteriovenous Fistula Failure

Distal arteriovenous fistula (AVF) failure remains a significant clinical problem, even in patients with apparently suitable vascular anatomy. This study aimed to evaluate the association between preoperative systemic immune-inflammation index (SII) and distal AVF failure after adjustment for detailed anatomical and clinical factors.

This retrospective single-center study included 209 patients who underwent distal AVF creation. Preoperative vascular anatomy was assessed using duplex ultrasonography, and systemic inflammatory status was evaluated using the systemic immune-inflammation index. The primary outcome was AVF failure. Univariable and multivariable logistic regression analyses were performed to identify independent predictors of AVF failure.

During follow-up, 41 AVFs (19.6%) failed. In univariable analyses, distal vein diameter was significantly associated with AVF outcome, whereas SII did not differ significantly between successful and failed AVFs. In multivariable analysis, smaller distal vein diameter was independently associated with a higher likelihood of AVF failure, while higher preoperative SII was also independently associated with AVF failure. Increasing age was independently associated with a lower likelihood of AVF failure after adjustment for distal vein diameter and systemic inflammatory burden. The adjusted model demonstrated moderate discriminative performance.

In an anatomically selected distal AVF cohort, systemic inflammation assessed by SII was independently associated with AVF failure, whereas favorable vascular anatomy remained the strongest determinant of outcome. Importantly, advanced age alone did not represent a limiting factor for distal AVF maturation when vascular anatomy and inflammatory status were taken into account. These findings suggest that SII may serve as a complementary risk modifier to anatomical assessment in distal AVF planning.