Neutrophil to lymphocyte ratio and five-year mortality in patients with acute ischemic stroke

BackgroundPrevious studies linked neutrophil to lymphocyte ratio (NLR) with short-term mortality after acute ischemic stroke (AIS), but its relationship with long-term mortality remains unclear. This study investigates the association between NLR and five-year mortality in AIS patients.MethodWe analyzed 416 AIS patients from April 2012 to January 2016 at Zhangjiagang TCM Hospital. Admission NLR was divided into quartiles: Q1 (<2.00), Q2 (2.00–3.05), Q3 (3.06–5.46), and Q4 (≥5.46). We assessed 5-year all-cause and vascular mortality using Kaplan-Meier, Cox regression, and receiver operating characteristic (ROC) curve analyses.ResultsOver five years, 134 (32.2 %) all-cause deaths and 114 (27.4 %) vascular deaths occurred. Elevated NLR was significantly associated with increased risks of all-cause and vascular mortality. Multivariate Cox analysis identified stroke history (HR: 1.57, 95 % CI 1.08–2.30), baseline National Institutes of Health Stroke Scale (NIHSS) score (HR: 1.09, 95 % CI 1.05–1.12), and NLR (HR: 1.09, 95 % CI 1.05–1.12) as independent risk factors for all-cause mortality. These factors also predicted 5-year vascular mortality: stroke history (HR: 1.65, 95 % CI 1.10–2.49), NIHSS score (HR: 1.10, 95 % CI 1.06–1.13), and NLR (HR: 1.08, 95 % CI 1.05–1.10). NLR quartiles were significantly linked to both outcomes: all-cause mortality HRs were Q2 (1.87, 95 % CI 1.00–3.51), Q3 (2.40, 95 % CI 1.31–4.39), Q4 (2.77, 95 % CI 1.47–5.24), P for trend = 0.001; vascular mortality HRs were Q2 (1.76, 95 % CI 0.88–3.55), Q3 (2.34, 95 % CI 1.14–4.40), Q4 (2.57, 95 % CI 1.28–5.16), P for trend = 0.002. Kaplan-Meier survival analysis revealed significantly higher mortality rates in higher NLR quartiles (log-rank p < 0.001). ROC analysis identified optimal NLR cutoff values of 3.42 for predicting 5-year all-cause mortality (AUC 0.689) and 3.51 for vascular-cause mortality (AUC 0.700), with moderate sensitivity and specificity.ConclusionsHigher NLR at admission was linked with five-year all-cause mortality and mortality attributed explicitly to vascular causes in AIS patients.