Neutrophil to Lymphocyte Ratio at Admission: Prognostic Factor in Patients With Acute Ischemic Stroke

Park, Jong Kyu; Oh, Hyung Geun; Park, Tai Hwan

Abstract

BACKGROUND
Inflammatory mechanisms play an important role in acute brain ischemia, and they contribute to the functional outcome. The neutrophil-to-lymphocyte ratio (NLR) has recently been described as a predictor of clinical outcomes in patients with acute coronary syndrome. This study assessed the clinical significance of NLR as a new predictor of the outcome in patients with acute ischemic stroke.
METHODS
The study included 371 patients diagnosed as acute ischemic stroke within 48 hours after the onset. All subjects were divided into three groups according to tertiles of the NLR in the initial blood test. Functional outcomes were divided into two groups at 3 months and 1 year after stroke onset: favorable (mRS 0~2) or unfavorable (mRS 3~6).
RESULTS
The proportion of patients with mRS 0~2 (favorable outcome) decreased as the NLR increased from the first tertile to the third tertile at discharge (74%, 62.9 and 49.2, p<0.001) and at 3 months (74%, 66.9 and 42.7, p<0.001) and 1 year (67.5%, 64.5 and 41.1, p<0.001) after stroke. NLR was higher in patients with an unfavorable outcome than in those with a favorable outcome (3.88 vs. 2.27 at 3 months, p<0.01; 3.67 vs. 2.31 at 1 year, p<0.001). Multivariate analysis revealed that the significant predictors of an unfavorable outcome at 3 months were NLR in the highest tertile (OR 2.28, 95% CI 1.13~4.60), age (OR 1.04, 95% CI 1.01~1.07), and NIHSS score (OR 1.27, 95% CI 1.18~1.36) at admission.
CONCLUSIONS
NLR at admission can be used as a predictor of functional outcome at 3 months after ischemic stroke.