Associations of Neutrophil-Lymphocyte Ratios with Reperfusion and Functional Outcomes in Ischemic Stroke after Endovascular Therapy

Abstract

ObjectivesTreatment of ischemic stroke with endovascular thrombectomy (EVT) leads to improved outcomes compared to IV tPA. The neutrophil-lymphocyte ratio (NLR), a marker of inflammation, has been proposed to predict outcomes in ischemic stroke patients and may be used to identify patients at risk for poor outcomes after EVT. Materials and MethodsThis was a retrospective study of adult ischemic stroke patients undergoing EVT between 1/1/2018 and 12/31/2020. Outcomes were successful reperfusion (TICI score ≥2B), favorable discharge NIHSS (≤4), favorable discharge and 3-month mRS (≤2), and symptomatic intracranial hemorrhage (sICH). The primary exposure was NLR, measured pre- and post-EVT. Other variables collected included demographics and timing of stroke onset, arrival, groin puncture, tPA, and recanalization. ResultsA total of 592 patients were included. The most common vessel involved was the middle cerebral artery (73%). Lower admission NLR was associated with favorable discharge NIHSS and favorable discharge and 3-month mRS (all P < 0.01). NLRs measured after EVT were associated with all the primary outcomes. Improvements in NLR after EVT were associated with favorable discharge (P = 0.02) and 3-month mRS (P = 0.02) and lower incidence of sICH (P = 0.01). ConclusionsBecause of the long-term functional deficits that can persist after ischemic stroke, it is vital to identify patients with higher probability for these outcomes. The results from this study showed that favorable NLR measures, as well as favorable trends in NLR over time, are associated with improved outcomes, indicating that NLR is a useful marker to identify patients at risk for poor functional outcomes.