The diagnostic value of the neutrophil-lymphocyte ratio in distinguishing between subarachnoid hemorrhage and migraine

ObjectiveMigraine and subarachnoid hemorrhage (SAH) patients present to emergency departments with the similar symptoms as headache, nausea, and vomiting.This study investigated whether the neutrophil-lymphocyte ratio (NLR) could distinguish patients with SAH from those with migraine.MethodsThis retrospective study was performed after research ethics committee approval. Data were gathered from the ED and neurology clinics of a university hospital between January 2015 and January 2016, from patients with symptoms of headache (primarily), nausea and vomiting. One hundred and twenty one with SAH, 123 patients with migraine and 987 with other primary headache syndromes were considered. Neutrophil-lymphocyte ratios (NLR-1) were compared between groups on admission. In SAH patients NLR taken on the 24th-30th hour of admission (NLR-2) was compared to admission NLR.ResultsNLR values, showed that the median NLR values of SAH patients were significantly higher than migraine and other headaches group values (p < 0.001; p < 0.001). There was no statistically significant difference between the NLR values of the migraine and control groups (p > 0.05). An NLR cut-off value of 4.02 produced 85.95% sensitivity, 97.46% specificity, a 33.79 positive likelihood ratio (LR+), and a 0.14 negative likelihood ratio (LR-). A statistically significant increase was observed in median NLR-2 values compared to median NLR-1 values in SAH patients (p < 0.001).ConclusionIn this retrospective analysis, NLR distinguished patients with SAH from those with migraine. Presence of SAH should be evaluated from discharged and readmitted patients (with headache symptoms) when an increase in NLR between initial and readmission levels is observed.