Neutrophil to lymphocyte ratio independently predicts cardiovascular events in patients with chronic kidney disease

Abstract

Increased inflammation is common in patients with chronic kidney disease (CKD) and is associated with increased adverse cardiovascular events (CVE). Neutrophil-to-lymphocyte ratio (NLR) was used to predict survival in patients with acute coronary syndrome. We aimed to evaluate predictive ability of NLR in CKD patients. 225 subjects with stage 3-5 CKD were followed for a mean of 39 months. Fatal and nonfatal CVE were recorded during this period. NLR at baseline was determined from complete blood count differential. Endothelial dysfunction (flow-mediated dilation, FMD), hsCRP and insulin resistance were determined. We investigated if NLR could predict development of fatal and nonfatal CVE. We also looked at how NLR and its individual components change across CKD stages and whether NLR is related to CRP, insulin resistance and endothelial dysfunction. There were 70, 74 and 81 patients in groups of CKD stage-3, stage-4 and stage-5, respectively. Median NLR was 2.81. NLR showed a significant increase from stage 3 to stage 5. NLR was inversely associated with FMD independent of hsCRP. 14 fatal and 52 nonfatal CVE occurred during follow-up period. NLR could predict composite CVE independent of insulin resistance and hsCRP. Increased NLR over 2.81 was related to a significantly decreased survival time (log-rank Chi-square = 14.833, P < 0.0001). A cutoff value for NLR ≥3.76 could predict development of composite CVE with 80.3 % sensitivity and 91.8 % specificity. NLR is independently related to endothelial dysfunction and could predict composite cardiovascular endpoints independent of traditional confounding factors in patients with moderate to severe CKD.