Association between systemic immune-inflammation index and systemic inflammation response index and in-stent restenosis in patients with hypertension complicated by coronary heart disease

Abstract Objective To investigate the association between the Systemic Immune-Inflammation Index (SII), Systemic Inflammation Response Index (SIRI), and in-stent restenosis (ISR) following percutaneous coronary intervention (PCI) in patients with hypertension complicated by coronary heart disease (CHD), and to evaluate the predictive value of these indices for ISR. Methods This retrospective study included 427 patients with hypertension and CHD who underwent PCI at our institution between June 2021 and April 2025. Patients were stratified by ISR occurrence at one-year follow-up coronary angiography. Multivariate logistic regression identified independent risk factors for ISR. Predictive performance was evaluated using receiver operating characteristic (ROC) curve analysis. Results The ISR group demonstrated significantly higher prevalence of diabetes mellitus and elevated levels of brain natriuretic peptide (BNP), glycosylated hemoglobin (HbA1c), low-density lipoprotein (LDL), monocyte-to-lymphocyte ratio (MLR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), SII, SIRI, neutrophil count, platelet count, and monocyte count compared with the non-ISR group, while lymphocyte count was significantly lower (P < 0.05). Multivariate analysis revealed that diabetes mellitus, elevated BNP, elevated LDL, elevated SII, and elevated SIRI were independent risk factors for ISR. The areas under the ROC curve (AUC) for SII, SIRI, and their combination in predicting ISR were 0.777 (95% CI: 0.719–0.834), 0.751 (95% CI: 0.697–0.805), and 0.807 (95% CI: 0.755–0.859), respectively. Conclusion Elevated SII and SIRI levels are independent risk factors for ISR following PCI in patients with hypertension and CHD. Both indices demonstrate robust predictive value for ISR, with combined assessment providing superior predictive performance.