Systemic immune inflammation index: is it a new marker for contrast-induced nephropathy?

Abstract

Introduction: Worldwide, >200 million patients are affected by peripheral arterial disease (PAD) and endovascular interventional treatments are increasingly being applied. Contrast-induced nephropathy (CIN) is the third most common cause of renal failure in hospitals. However, factors such as renal vasoconstriction, decrease in renal blood flow, endothelial dysfunction, and oxidative stress have been suggested in the etiology of CIN. Studies are showing that inflammatory markers increase in CIN. Systemic immune inflammation index (SII), a newly defined parameter, is calculated by multiplying the platelet and lymphocyte counts and dividing by the neutrophil count. Studies are showing that this parameter influences prognosis in various cancer types. Considering that inflammation may play a role in CIN, we planned this study to investigate the role of SII in patients undergoing percutaneous peripheral vascular interventions. Material and Method: 300 patients who underwent percutaneous peripheral vascular interventions between August 2018-December 2021 due to peripheral arterial disease were included in the study. The data of the patients were scanned retrospectively from the patient files. The neutrophil-lymphocyte ratio (NLR) was calculated by dividing the neutrophil count by the lymphocyte count. SII was found by multiplying NLR with platelet count Results: Contrast-induced nephropathy developed in 41 (12.3%) patients. CIN(+) patients also, had higher CRP levels (5.1±0.7vs 2.4±0.4,P<0.05), NLR (4.07±1.07vs 2.65±0.84, P<.005), SII score (1778±627.57vs 867.14±491.88, P<.005.) the contrast media used was also higher in CIN(+) patients (176.19±48.44 vs 128.72±48.44;P<0.05) Multivariate logistic regression analysis demonstrated that a high SII score was an independent predictor of development of CIN (odds ratio [OR]: 1.002, 95% confidence interval [CI]: 1.001-1.002, P<.0005) together with high NLR (OR: 3.56, 95% CI: 1.905-6.675, P<.005) and CRP (OR: 1.002, 95% CI: 1.001-1.002, P<.005 Receiver operating characteristic curve analysis demonstrated that the best cutoff value of 1224 for SII to predict the development of CIN with 85% sensitivity and 72% specificity (area under ROC curve 0.904 [95% CI: 0.866-0.942], P<.005). Conclusion: Imbalance in inflammatory cells, the increase in neutrophils, and the decrease in lymphocytes play a role in developing kidney damage. Impaired immune functions due to lymphocytopenia contribute to the development of acute kidney injury. Oxidative stress exacerbates the inflammatory state by increasing inflammatory cell infiltration. AS a result, SII may be a powerful predictor of inflammation and can be used to determine the risk before interventional procedures.