Prognostic value of aggregate index of systemic inflammation in acute ischemic stroke mortality

Aim: Systemic inflammation plays a key role in the pathophysiology of acute ischemic stroke (AIS), influencing disease severity and outcomes. The Aggregate Index of Systemic Inflammation (AISI) is a novel inflammatory biomarker that integrates multiple hematological parameters. This study aimed to evaluate the prognostic value of AISI in predicting 30-day mortality in AIS patients. Material and Methods: This retrospective cohort study included patients diagnosed with AIS in the emergency department of a tertiary care hospital between January 1, 2022, and January 1, 2025. AISI was calculated as (Neutrophil count × Monocyte count × Platelet count) / Lymphocyte count, with all components expressed in absolute values (×10⁹/L). The primary outcome was 30-day all-cause mortality. Logistic regression analysis was performed to assess the independent prognostic value of AISI. Model performance was evaluated using accuracy, sensitivity, specificity, and the area under the receiver operating characteristic curve (AUROC). Results: A total of 663 AIS patients were analyzed, including 573 survivors (86.4%) and 90 non-survivors (13.6%). AISI values were significantly higher in non-survivors compared to survivors (755.4 ± 410.8 vs. 396.7 ± 216.1, p < 0.001). Multivariate logistic regression analysis identified AISI as an independent predictor of 30-day mortality (OR: 1.10, 95% CI: 1.02–1.19, p = 0.040). The AUROC for AISI was 0.820, indicating good discriminatory ability. Conclusions: AISI was found to be an independent predictor of 30-day mortality in AIS patients, highlighting the potential role of systemic inflammation in stroke prognosis. Given its accessibility and ease of calculation, AISI could serve as a useful marker for early risk stratification in clinical practice. However, further prospective, multicenter studies are needed to validate its clinical utility and compare it with other established inflammatory indices.