Prognostic value of the aggregate index of systemic inflammation in predicting in-hospital adverse outcomes among patients with ST-segment elevation myocardial infarction undergoing primary percutaneous intervention

Abstract

Inflammation plays a pivotal role in the initiation and progression of atherosclerosis and acute coronary syndromes. The Aggregate Index of Systemic Inflammation (AISI), a novel biomarker derived from neutrophil, monocyte, platelet, and lymphocyte counts, reflects the systemic inflammatory response. Although AISI has demonstrated prognostic value in various cardiovascular settings, its utility in its association with in-hospital adverse outcomes among patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) remains unclear. This study aimed to evaluate whether AISI reflects systemic inflammatory burden and its association with in-hospital adverse outcomes in STEMI patients undergoing primary PCI. Materials and methods This retrospective, single-center study included 2,678 consecutive STEMI patients who underwent primary PCI. AISI was calculated as (neutrophil × monocyte × platelet) / lymphocyte, and patients were stratified into high and low AISI groups according to the median value. The primary outcomes were in-hospital mortality and major adverse cardiac and cerebrovascular events (MACCE). Secondary endpoints included arrhythmic complications, acute stent thrombosis, and ischemic stroke. Results Patients with high AISI were older, had higher rates of diabetes and hypertension, elevated glucose and creatinine, and lower left ventricular ejection fraction. High AISI was associated with mortality and MACCE in univariate analyses, whereas continuous AISI showed only a statistically significant but clinically modest association after multivariable adjustment when expressed per 100-unit increase. These findings indicate that AISI has limited standalone prognostic value and should be interpreted as an adjunctive inflammatory marker. Elevated AISI showed an independent association with ischemic stroke (adjusted OR = 4.77, 95% CI 1.02–22.30, p = 0.047); however, this finding should be interpreted cautiously given the low number of events and wide confidence intervals. ROC analysis showed moderate discriminative performance for in-hospital mortality (AUC = 0.64), MACCE (AUC = 0.60), and ischemic stroke (AUC = 0.70). Conclusion AISI is a simple, cost-effective inflammatory marker that may aid in risk stratification for in-hospital adverse and cerebrovascular outcomes in STEMI patients undergoing primary PCI.