Introduction

Contrast-associated acute kidney injury (CA-AKI) is a complication after peripheral endovascular interventions, but the value of the inflammatory burden index (IBI) in this setting is unknown.

Aim

To evaluate the association between pre-procedural IBI and CA-AKI after iliac artery intervention, compare its performance with other inflammatory indices, and examine its relationship with TASC II lesion complexity.

Material and methods

This retrospective study included 417 patients treated between January 2020 and December 2025. IBI was calculated as C-reactive protein multiplied by the neutrophil-to-lymphocyte ratio. CA-AKI was defined as a serum creatinine increase of ≥ 0.5 mg/dl or ≥ 25% within 72 h. Receiver operating characteristic analysis, DeLong testing, multivariable logistic regression with multiple imputation, restricted cubic splines, and bootstrap validation were performed.

Results

CA-AKI occurred in 70 (16.8%) patients. IBI showed the highest discrimination for CA-AKI (AUC = 0.857, 95% CI: 0.810–0.904), outperforming C-reactive protein, neutrophil-to-lymphocyte ratio, systemic immune-inflammation index, and aggregate index of systemic inflammation (all p < 0.001). At a cutoff of 40.6, sensitivity and specificity were 80.0% and 80.2%, respectively. Each doubling of IBI was independently associated with CA-AKI (adjusted OR = 3.19, 95% CI: 2.22–4.59; p < 0.001). The association was nonlinear (p for nonlinearity < 0.001). IBI was also independently associated with TASC II C–D lesions (adjusted OR per doubling 2.91, 95% CI: 2.29–3.71; p < 0.001).

Conclusions

Pre-procedural IBI was independently associated with CA-AKI and complex iliac lesion morphology and outperformed the other evaluated inflammatory indices. External validation is required before clinical implementation.