Association between systemic immune-inflammation index and all-cause mortality in ischemic stroke patients

Junmou Li1, Zhenwei Wang2, Xuerong Sun1

  • 1Department of Rehabilitation Medicine, Dandong Central Hospital, China Medical University, Dandong, Liaoning, China.

Frontiers in Neurology
|April 24, 2026
PubMed

Insights

The systemic immune-inflammation index (SII) is linked to a higher risk of death in ischemic stroke patients. Higher SII levels indicate a significantly increased risk of all-cause mortality in this population.

Area of Science:

  • Cardiovascular Research
  • Immunology
  • Stroke Medicine

Background:

  • Ischemic stroke (IS) poses a significant global health burden.
  • Identifying reliable prognostic markers for IS patients is crucial for risk stratification and management.
  • The systemic immune-inflammation index (SII) reflects the balance between pro-inflammatory and anti-inflammatory cells.

Purpose of the Study:

  • To investigate the association between the systemic immune-inflammation index (SII) and all-cause mortality in patients with ischemic stroke (IS).
  • To evaluate the predictive value of SII for mortality in IS patients.
  • To compare the predictive performance of SII with other inflammatory markers.

Main Methods:

  • A retrospective cohort study of 1,156 IS patients.
  • Calculation of SII using the formula: (neutrophil count × platelet count)/lymphocyte count.
  • Multivariate Cox regression, subgroup and sensitivity analyses, ROC curve, and Kaplan-Meier survival analysis were employed.

Main Results:

  • An elevated SII was significantly associated with increased all-cause mortality risk in IS patients (HR=1.172 per SD increase).
  • High SII group demonstrated 1.543 times higher risk of all-cause mortality compared to the low SII group.
  • SII showed predictive value for mortality (AUC=0.605), outperforming PLR and MHR, and improved when combined with NIHSS and mRS scores (AUC=0.683).

Conclusions:

  • Higher systemic immune-inflammation index (SII) levels are significantly associated with an increased risk of all-cause mortality in patients with ischemic stroke.
  • SII serves as a valuable prognostic biomarker for predicting mortality in IS patients.
  • The combination of SII with clinical scores may enhance mortality prediction in IS.
Abstract

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