Introduction: As indicators of the systemic inflammatory response, the neutrophil-to-lymphocyte ratio (NLR) have been proposed to predict the clinical outcome in cardiovascular disease, diabetes, and various malignancies. We assessed the significance of NLR as a predictor of the outcome in patients with acute ischemic stroke.
Methods: We retrospectively analyzed the clinical characteristics, laboratory parameters, and NLR in 356 consecutive patients (62.2% men, mean age 65.8±13.0 years) within 3 days after the onset of acute ischemic stroke between July 2012 and March 2015. The NLR was calculated from the differential counts by dividing the neutrophil number by the lymphocyte number at the time of admission. All subjects were divided into four groups according to quartiles of the NLR. Outcomes were measured as 3-month modified Rankin scale (mRS) score. A good functional outcome was defined as a mRS of 0-2 points, whereas a poor outcome was defined as a mRS of >2 points. Multivariate logistic regression analysis was used to assess association among the clinical, inflammatory and serological parameters including NLR and mRS scores.
Results: The frequency of atrial fibrillation, heart failure, hypertension, and diabetes, the NIHSS score at admission, and the level of hs-CRP, D-dimer and the NLR were each significantly higher in the poor outcome group (p < 0.05).
The cut-off values of NLR and NIHSS score at admission for prediction of the poor outcome were 2.135 (sensitivity 0.864 and specificity 0.533) and 3.5 (sensitivity 0.862 and specificity 0.787), respectively. In age-adjusted analysis, the NLR were significantly correlated with 3-month mRS score (partial r = 0.329, p < 0.001) and NIHSS score at discharge (partial r = 0.301, p < 0.001). Multivariate logistic regression analysis demonstrated that age of ≥65 (OR, 10.2; 95% CI, 3.31-31.21, p < 0.001), presence of diabetes mellitus (OR, 3.3; 95% CI, 1.36-8.12, p = 0.008), NIHSS score of ≥4 (OR, 26.4 95% CI, 9.81-71.15, p < 0.001), NLR of ≥2.135 (OR, 9.2; 95% CI, 3.18-26.4, p < 0.001) were independently associated with poor functional outcome.
Conclusion: The NLR is a useful marker for short-term functional outcome in acute ischemic stroke. The NLR may have a role in risk stratification for predicting poor outcome.