Systemic Inflammation Response Index and Systemic Immune-Inflammation Index Are Associated with Clinical Outcomes in Patients Treated with Mechanical Thrombectomy for Large Artery Occlusion

Inflammation plays a pivotal role in acute ischemic stroke, and various inflammatory markers are known to predict prognosis of acute ischemic stroke. This study aimed to evaluate the prognostic value of systemic inflammation response index (SIRI) and systemic immune-inflammation index (SII) after mechanical thrombectomy (MT) for acute ischemic stroke caused by large artery occlusion.The study enrolled 440 patients who underwent MT for large artery occlusion. SIRI and SII were calculated using laboratory data on admission. Prognosis was estimated with modified Rankin Scale at 3 months, and favorable clinical outcome was defined by a modified Rankin Scale score of 0-2. Receiver operating characteristic analysis was used to calculate the optimal cutoff values of SIRI and SII for predicting clinical outcome. Multivariate analysis was used to assess the relationship of SIRI and SII with clinical outcome.In receiver operating characteristic analysis, the optimal cutoff values for SIRI and SII were 2.9 and 853, respectively (area under the curve 0.799, 95% confidence interval [CI] 0.756-0.843, P < 0.001 and area under the curve 0.679, 95% CI 0.643-0.745, P < 0.001, respectively). Multivariate analysis revealed that SIRI <2.9 (odds ratio 2.27, 95% CI 1.29-5.17, P = 0.019) and SII <853 (OR 1.82, 95% CI 1.16-3.10, P = 0.031) were independent predictors of favorable clinical outcome after MT.Decreased SIRI and SII were associated with favorable clinical outcome after MT. SIRI and SII represent potential prognostic factors in patients undergoing MT for large artery occlusion.