Dynamic changes of systemic immune-inflammation index and systemic inflammation response index after mechanical thrombectomy and their predictive value for functional outcomes in patients with acute ischemic stroke

Abstract

Objective: To investigate the dynamic changes in the systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) after mechanical thrombectomy (MT) and their ability to predict 90-day functional outcomes in acute ischemic stroke (AIS) patients.

Methods: This retrospective cohort study included 423 AIS patients who underwent MT treatment at a single center between January 2018 and February 2024. SII and SIRI were measured at admission, Day 1, and Day 3 post-MT. The primary outcome was poor functional outcome (modified Rankin Scale score > 2) at 90 days. Receiver operating characteristic curve (ROC) analysis and multivariable logistic regression were used to assess the predictive performance and independent associations of SII and SIRI with outcomes. The relationships between SII, SIRI, and 90-day mRS scores were explored using Spearman correlation analysis and multivariable linear regression models.

Results: The poor outcome group had significantly higher SII and SIRI at all time points compared to the good outcome group (all P < 0.001). ROC analysis showed that SII and SIRI on day3 had the strongest predictive power (SII: AUC=0.80; SIRI: AUC=0.82). After adjusting for potential confounders, multivariable logistic regression analysis indicated that SII and SIRI on day3 were independently associated with poor outcomes at 90 days (Both P < 0.001). Multivariable linear regression analysis further confirmed that SII and SIRI on day3 were significantly positively correlated with mRS scores (both P < 0.01).

Conclusion: SII and SIRI levels after MT (especially on day3) can serve as effective predictors of 90-day functional outcomes in AIS patients.