EVALUATING THE SYSTEMIC IMMUNE-INFLAMMATION INDEX FOR ADVERSE OUTCOMES IN ELDERLY ACUTE CORONARY SYNDROME PATIENTS

Introduction: Acute coronary syndrome is a fatal clinical manifestation of coronary artery disease. A newly defined index-Systemic Immune- Inflammation Index-has recently been reported to have prognostic value in patients with cardiovascular disease. This investigation was aimed at evaluating the systemic immune-inflammation index predictive value for in-hospital and 1-year follow-up clinical outcomes in elderly patients with acute coronary syndrome. Materials and method: We retrospectively enrolled 910 consecutive patients in the study. We divided the patients into two groups: young patients with acute coronary syndrome (Group 1) and elderly patients with acute coronary syndrome (Group 2). The patients were followed up on for one year. We compared the two groups' systemic immune-inflammation index results, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio. Results: The neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and systemic immune-inflammation index were significantly higher in Group 2. According to multivariate logistic regression analyses, systemic immune-inflammation index, and platelet-to-lymphocyte ratio (p < 0.001, and p = 0.013, respectively) emerged as independent predictors of in-hospital mortality in Group 2. Group 2 had significantly worse in-hospital mortality rates than those of Group 1. However, the groups' long-term outcomes were similar. Conclusion: High systemic immune-inflammation index values were independently associated with an elevated risk of in-hospital mortality in Group 2. This investigation may be the first to demonstrate that this index is independently linked with in-hospital and long-term mortality in elderly acute coronary syndrome patients. It could be used as an easy, inexpensive, and practical predictor to identify high-risk elderly patients with acute coronary syndrome.