Neutrophil Lymphocyte Ratio as a Predictor of Stroke

Abstract

The aim of this study is to investigate the relationship of the neutrophil to lymphocyte ratio (NLR) with short-term mortality in acute stroke. This retrospective study included 255 patients with acute cerebral infarction who presented within 24 hours of symptom onset. A hemogram from peripheral venous blood samples was taken at the time of admission. The NLR was calculated as the ratio of neutrophils to lymphocytes. Duration of follow-up was defined as 60 days. Seventy-one of 255 patients died during the follow-up period. The median NLR was significantly increased among the mortality group compared with the survival group (median 11.50, interquartile ratio [IQR] 10.40 vs median 3.79, IQR 4.72; P = .001). In our multivariate Cox regression model, NLR >5.0 (hazard ratio [HR] 3.30; 95% confidence interval [CI] 1.35-8.07), National Institutes of Health Stroke Scale score (HR 1.11; 95% CI 1.07-1.16), glucose values at admission (HR 1.007; 95% CI 1.002-1.011), and history of coronary artery disease (HR 2.49; 95% CI 1.26-4.92) were predictors of short-term mortality. The sensitivity for short-term mortality when the NLR was >5 was 83.10%, and the specificity was 62.00%. The positive predictive value of a NLR >5 was 45.7%, and negative predictive value was 90.50%. A strong linear association between NLR and National Institutes of Health Stroke Scale score was also observed (r = 0.64; P = .001). In addition, the NLR was higher in both the atherosclerotic and cardioembolic stroke subgroups than the lacunar infarct subgroup (6.5 [IQR 7.2], 7.5 [IQR 8.9], and 3.20 [IQR 3.50], respectively; P = .001). The NLR at the time of hospital admission may be a predictor of short-term mortality in acute stroke patients. Because of the routine use and inexpensive nature of hemogram analysis, the NLR should be investigated in future prospective, randomized controlled trials investigating acute stroke.