The association of neutrophil-lymphocyte ratio with stroke recurrence in patients with symptomatic nonacute atherosclerotic internal carotid artery occlusion.

Background: Atherosclerotic internal carotid artery occlusion (AICAO) is associated with a high risk of stroke recurrence despite standard medical therapy. This study aimed to evaluate the predictive value of the neutrophil-lymphocyte ratio (NLR), an accessible marker of systemic inflammation, for identifying patients at higher risk of recurrent stroke. Methods: This retrospective study enrolled 136 patients with AICAO, whose NLR data were collected. Recurrent stroke was evaluated via clinical and vascular imaging follow-up. Receiver operating characteristic (ROC) analysis was performed to determine the optimal NLR cutoff value. The value of NLR in predicting stroke recurrence was determined via a Cox regression model. Results: Of the 281 initially screened patients, 136 met the study's inclusion criteria (age 62±10 years; 68% male). Among the patients, 17 (12.5%) experienced ipsilateral stroke (1-year rate, 8.8%; 2-year rate, 12.5%). The median baseline NLR was higher in patients with recurrence [3.38, interquartile range (IQR), 2.20-4.95] than in those without recurrence (2.39, IQR, 1.82-3.02) (Mann-Whitney P=0.007). The ROC analysis indicated an optimal NLR cutoff of 3.36 [area under the curve (AUC) =0.703; 95% confidence interval (CI): 0.559-0.847; P=0.007; sensitivity =0.59; specificity =0.82]. Patients were stratified into NLR-high (>3.36; n=31) and NLR-low (≤3.36; n=105) groups, with the 1-year stroke rates being 22.5% (7/31) and 5.7% (6/105), respectively, with an absolute risk difference of 16.8% (95% CI: 3.4-30.2%). In the Kaplan-Meier analysis, the log-rank P value was 0.039. In the univariate Cox analysis, an NLR >3.36 yielded a hazard ratio (HR) of 3.83 for stroke recurrence (95% CI: 1.48-9.94; P=0.006). In the multivariable Cox analysis, an NLR >3.36 remained independently associated with recurrence (HR 4.17, 95% CI: 1.59-10.91; P=0.004). When NLR was modelled as a continuous log-transformed variable, each 1-unit increase yielded an HR of 1.99 (95% CI: 1.49-2.66; P<0.001). Conclusions: In symptomatic nonacute patients with AICAO, NLR is a predictor for recurrent stroke under standard medical treatment. Moreover, an NLR >3.36 is associated with a higher risk of stroke recurrence, and intensive surveillance in high-risk patients with this marker may be necessary.