Systemic Immune-Inflammation Index as an independent predictor of in-hospital morbidity in diabetic patients with ST-elevation myocardial infarction

Diabetic patients presenting with ST-elevation myocardial infarction (STEMI) are particularly vulnerable to unfavorable in‑hospital outcomes. We examined the prognostic value of the systemic immune‑inflammation index (SII) for predicting in‑hospital morbidity in a prospective cohort of 108 diabetic patients with STEMI; patients were classified by clinical outcome into morbid (n=57) and non‑morbid (n=51) groups. Demographic characteristics, clinical findings, laboratory results, and angiographic data were recorded. In-hospital morbidity occurred in 52.8% of patients. Multivariate logistic regression identified prior myocardial infarction [p=0.038, odds ratio (OR)=3.34, 95% confidence interval (CI): 1.07-11.01], three‑vessel disease (p=0.019, OR=3.81, 95% CI: 1.26-19.51), and SII (p=0.022, OR=3.16, 95% CI: 1.12-14.5) as independent predictors of morbidity. SII demonstrated good discriminatory ability for predicting morbidity with an area under the receiver operating characteristic curve of 0.718 (95% CI: 0.662-0.844, p<0.001); at a cut‑off >604.75 the sensitivity was 77% and specificity 63%. These findings suggest that SII is a useful and readily available inflammatory marker for predicting in‑hospital morbidity among diabetic patients with STEMI.