Association of a High Neutrophil-to-Lymphocyte Ratio with Hyperdense Artery Sign and Unfavorable Short-Term Outcomes in Patients with Acute Ischemic Stroke

PURPOSE: Immune–inflammatory processes are involved in all the stages of stroke. This study investigated the association of the neutrophil-to-lymphocyte ratio (NLR) with the hyperdense artery sign (HAS) observed on brain computed tomography (CT) and with clinical features in patients with acute ischemic stroke. METHODS: We retrospectively enrolled 2903 inpatients with acute ischemic stroke from May 2010 to May 2019. Data collected included imaging studies, risk factors, laboratory parameters, and clinical features during hospitalization. RESULTS: The HAS was identified in 6% of the 2903 patients and 66% of the 236 patients with acute middle cerebral artery occlusion. Patients with the HAS had a higher NLR. HAS prevalence was higher in men and patients with cardioembolism. The NLR exhibited positive linear correlations with age, glucose and creatinine levels, length of hospital stay, initial National Institutes of Health Stroke Scale (NIHSS) scores, and mRS scores at discharge. The NLR was significantly higher in patients with large-artery atherosclerosis and cardioembolism and was the highest in patients with other determined etiology. Multivariate analysis revealed that an initial NIHSS score of ≥10 and an NLR of >3.5 were significant positive factors, whereas diabetes mellitus and age > 72 years were significant negative factors for the HAS, with a predictive performance of 0.893. An initial NIHSS score of ≥5, positive HAS, age > 75 years, diabetes mellitus, an NLR of >3.5, female sex, a white blood cell count of >8 × 10(3)/mL, and elevated troponin I were significant predictors of unfavorable outcomes, with a predictive performance of 0.886. CONCLUSION: An NLR of >3.5 enabled an efficient prediction of CT HAS. In addition to conventional risk factors and laboratory parameters, both an NLR of >3.5 and CT HAS enabled improved prediction of unfavorable stroke outcomes.