Comparison of Lymphocyte Count, Neutrophil to Lymphocyte Ratio and Platelet to Lymphocyte Ratio in Predicting the Severity and the Clinical Outcomes of Acute Cerebral Infarction Patients

Background: To compare the prediction values of lymphocyte counts, neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR) for the severity and the clinical outcomes of acute cerebral infarction (ACI). Methods: A total of 139 patients diagnosed with ACI were enrolled in this study. Data were gathered from medical records of patients who were admitted to the Fourth Affiliated Hospital Zhejiang University School of Medicine. Stroke severity was evaluated using the National Institutes of Health Stroke Scale (NIHSS). The clinical outcomes of ACI patients were evaluated using the Glasgow Outcome Scale (GOS) at day 30. Patients were classified into two groups based on their GOS at day 30. The Student's t-test of independent samples was adopted for the comparison of the mean between two groups. The lymphocyte counts, NLR and PLR were evaluated by comparing the areas under the receiver operating characteristic curve (AUC) in predicting the clinical outcomes of ACI. The linear correlations were specifically evaluated to determine the relationship between lymphocyte counts, NLR, PLR and the NIHSS score and the clinical outcomes of ACI. Comparison of AUC was performed using the Z-test. Results: The lymphocyte counts were significantly decreased in the poor outcomes group compared with the good outcomes group of ACI, while NLR and PLR were significantly increased (all p < 0.05); moreover, AUC in predicting 30-day poor outcomes of ACI was 0.697 (95% confidence interval (CI), 0.614 to 0.772) for lymphocyte counts, 0.744 (95% CI, 0.663 to 0.814) for NLR, and 0.689 (95% CI, 0.605 to 0.764) for PLR, but there were no significant statistical differences (all p > 0.05). Finally, the lymphocyte counts were negatively correlated with the NIHSS score of ACI patients, while NLR and PLR were positively correlated (all p < 0.05); on the other hand, the lymphocyte counts were positively correlated with the GOS score of ACI patients, while NLR and PLR were negatively correlated (all p < 0.05). Conclusions: As an inflammatory and immune biomarker, lymphocyte counts demonstrate similar test performance as NLR and PLR for predicting the severity and 30-day poor outcomes of ACI.