Predictive Value of the Systemic Immune‐Inflammation Index and CRUSADE Score for Bleeding and Mortality in Older Patients With Acute Coronary Syndrome

BACKGROUND: There are currently no adequate studies evaluating the relationship between the systemic immune-inflammation index (SII) and bleeding in older patients presenting with acute coronary syndrome (ACS). This study investigated the predictive value of SII for in-hospital bleeding and the CRUSADE Bleeding Score (CBS) for long-term mortality in older patients with ACS. METHODS: The study included 367 older patients, aged 75 years and above, admitted with ACS between April 2015 and January 2023. Predictors of in-hospital bleeding were determined using multivariate logistic regression analysis. Survival curves were generated using the Kaplan-Meier method. RESULTS: The patients' median age was 81 (77-85), and 179 (48.8%) were male. The median follow-up was 24 months (Q1-Q3: 5-47, maximum: 96). In-hospital bleeding was significantly elevated in patients in the high SII group (p = 0.005); all long-term mortality was significantly increased in those with a high CBS (p = 0.001). Multivariate logistic regression analysis revealed that the estimated glomerular filtration rate (eGFR) (odds ratio [OR]: 0.980, 95% confidence interval [CI]: 0.964-0.995, p = 0.009) and SII (OR: 1.001, 95% CI: 1.001-1.003, p = 0.001) were independent predictors of in-hospital bleeding. Kaplan-Meier analysis confirmed that the all-cause mortality rate in patients with high CBS (≥ 46) was significantly higher than that of patients with low CBS (Long Rank: 37.12, p = 0.001). CONCLUSION: A high SII was an independent predictor of in-hospital bleeding, and a high CBS at admission was associated with increased long-term mortality in older patients with ACS.