Neutrophil-to-Lymphocyte Ratio Correlates with Severity of Extracranial Carotid Stenosis—A Study Using Digital Subtraction Angiography

Abstract

Although neutrophil-to-lymphocyte ratio (NLR) has been reported to correlate with subclinical atherosclerosis, little is known about the relationship between NLR and carotid stenosis. Only patients with extracranial carotid stenosis in digital subtraction angiography (N = 105) were enrolled in this study. Maximal and accumulated extracranial carotid artery stenosis was measured. Stepwise multiple linear regression was performed to identify independent factors associated with maximal and accumulated extracranial carotid artery stenosis. Receiver operating characteristic curve was conducted to define the cutoff value of NLR for predicting 50% maximal extracranial carotid stenosis or greater. Univariate analysis showed maximal extracranial carotid stenosis was positively associated with white blood cell (WBC) count (r = .235, P = .016), neutrophil absolute value (r = .334, P = .000), and NLR (r = .419, P = .000), and negatively associated with high-density lipoprotein cholesterol (HDL-c) (r = -.208, P = .034). Accumulated extracranial carotid stenosis was positively associated with WBC count (r = .210, P = .032), neutrophil absolute value (r = .320, P = .001), and NLR (r = .437, P = .000), and negatively associated with lymphocyte absolute value (r = -.195, P = .047) and HDL-c(r = -.263, P = .007). Stepwise multiple linear regression demonstrated NLR and HDL-c levels were significant and independent factors associated with maximal extracranial carotid stenosis (adjusted R2 = .179, P < .001), and NLR was a significant and independent factor associated with accumulated extracranial carotid stenosis (adjusted R2 = .183, P < .001). The cutoff value of NLR was predictive at 1.89 with 78.4% sensitivity and 77.4% specificity for 50% maximal extracranial carotid stenosis or greater. NLR positively correlates with both maximal and accumulated extracranial carotid stenosis. NLR may be a useful factor for assessing the severity of extracranial carotid stenosis.