Neutrophil-to-Lymphocyte Ratio Predicts Contrast- Induced Acute Kidney Injury in Patients with STElevation Myocardial Infarction Treated with Primary Percutaneous Coronary Intervention

Background: Development of contrast-induced acute kidney injury (CI-AKI) in patients with ST-elevation myocardial infarction (STEMI) treated via primary percutaneous coronary intervention (PCI) is a major cause of morbidity and mortality worldwide. The neutrophil-to-lymphocyte ratio (NLR), which is a marker of inflammation, has been demonstrated to be associated with the development of major adverse cardiovascular outcomes in many studies. From this point of view, in this study, we aimed to evaluate the predictive value of the NLR as regards the occurrence of CI-AKI in patients with STEMI undergoing primary PCI. Methods: This study was conducted at Dr. Siyami Ersek Training and Research Hospital from May 2008 to June 2016. A total of 2000 patients with STEMI treated via primary PCI were enrolled in the study. The NLR was calculated as the ratio of the number of neutrophils to the number of lymphocytes. All venous blood samples were obtained within 8 hours after admission. CI-AKI was the primary end point of the study. Then, the relationship between CI-AKI and the NLR was assessed. Results: CI-AKI was detected in 148 (7.4%) patients. The patients who developed CI-AKI had a significantly higher NLR than those who did not (7.08±4.43 vs. 6.18±3.98; P=0.011). In the multivariate logistic regression analyses, the NLR remained a significant independent predictor of CI-AKI (OR: 1.78, 95% CI: 1.21–2.61, and P=0.003). Conclusion: The NLR may be a significant independent predictor of CI-AKI in patients with STEMI treated via primary PCI and higher NLR values could be independently associated with a greater risk for CI-AKI.