Systemic Inflammation Indices in Patients With Acute Ischemic Stroke Treated With Intravenous Tissue Plasminogen Activator: Clinical Yield and Utility

Abstract

Inflammation indices derived from complete blood counts (CBCs) have been proposed to estimate benefit and risk of intravenous (IV) tissue plasminogen activator (tPA) in acute ischemic stroke. In 165 acute ischemic patients, the neutrophil-to-lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio, and systemic immune-inflammation index (SII) were calculated before and 24 hours after IV tPA. The area under receiver operating characteristic (AUC-ROC) curves, and positive and negative likelihood ratios (+LR,−LR) were produced to measure their diagnostic accuracy and clinical utility for tPA effectiveness, hemorrhage risk and third-month prognosis. None of the indices obtained “before” IV-tPA was found to be useful in determining acute and long-term functional efficacy and bleeding risk. Lymphocyte decrease, neutrophil increase, and parallel NLR and SII increase at the 24th-hour were associated with poor functional outcome. However, their clinical utility was not sufficient due to absence of effective thresholds. NLR threshold >5.65 provided ROC-AUC 0.86, sensitivity 71.3%, specificity 65.7%, −LR 0, +LR 3.76, and SII threshold >1781 had ROC-AUC 0.802, sensitivity 58.7%, specificity 72.7%, −LR 0.11, +LR 4.52, corresponding to an acceptable clinical yield. Systemic immune-inflammation index and NLR, but not other CBC-derived inflammatory parameters, have moderate utility as marker of tPA-related symptomatic hemorrhage occurrence.