High neutrophil‐to‐lymphocyte ratio is a predictor of poor short‐term outcome in patients with mild acute ischemic stroke receiving intravenous thrombolysis

INTRODUCTION: Very few studies have investigated the specific relationship between neutrophil‐to‐lymphocyte ratio (NLR) and the short‐term outcomes of patients suffering from mild acute ischemic stroke (AIS) and receiving intravenous thrombolysis (IVT). This study aimed to investigate whether a high NLR is associated with a poor short‐term outcome in patients with mild AIS after IVT. METHODS: We retrospectively analyzed data that were prospectively acquired from patients with AIS treated with IVT. Mild AIS was defined as a National Institutes of Health Stroke Scale (NIHSS) score ≤ 7 on admission. The NLR was based on a blood test performed prior to IVT and was classified as ‘high’ when exceeding the 75th percentile. Follow‐ups were performed at discharge and 3 months after onset. A poor outcome was defined as a modified Rankin scale (mRS) ≥3. RESULTS: A total of 192 patients were included in this study. The median NLR was 3.0 (interquartile range [IQR]: 2.0–3.9). Fifty‐one patients (26.6%) had a high NLR (≥3.9) on admission. Forty‐one patients (21.4%) had a poor outcome at discharge, while 34 patients (17.7%) had a poor outcome at 3 months. Patients with a poor outcome at discharge, and at 3 months after onset, were more likely to have a high NLR at discharge (42.9% vs. 21.9%; p = .005) and at 3 months (44.1% vs. 22.8%; p = .011), compared with those with a better outcome. After adjustment for NIHSS score on admission, ipsilateral severe intracranial large artery occlusion, and atrial fibrillation, logistic regression analyses revealed that a high NLR was a significant predictor of poor outcome at discharge and at 3 months after onset. CONCLUSIONS: A high NLR on admission could be a useful marker for predicting poor short‐term outcome in patients with mild AIS following IVT.