Prognostic significance of IL-18 in acute coronary syndrome patients

Background: After acute coronary syndrome (ACS), inflammation aids healing but may harm the heart. Interleukin (IL)-18 and IL-1 beta are pivotal proinflammatory cytokines released during pyroptosis, a process that initiates and sustains inflammation. This study aimed to evaluate the levels of circulating IL-18 and IL-1 beta during the progression of ACS and to determine their association with subsequent clinical events in ACS patients. HypothesisCirculating levels of IL-18 and IL-1 beta are associated with subsequent clinical events in ACS patients. Methods: Employing immunoassays, we examined plasma levels of IL-1 beta and IL-18 in 159 ACS patients and matched them with 159 healthy controls. The primary composite endpoint included recurrent unstable angina, myocardial infarction, heart failure exacerbation, stroke, or cardiovascular death. Results: ACS patients exhibited a significant increase in plasma IL-18 levels, measuring 6.36 [4.46-9.88] x 10(2) pg/mL, in contrast to the control group with levels at 4.04 [3.21-4.94] x 10(2) pg/mL (p < 0.001). Conversely, plasma levels of IL-1 beta remained unchanged compared to the control group. Following a 25-month follow-up, IL-18 levels exceeding the median remained an important prognostic factor for adverse clinical events in ACS patients (hazard ratio = 2.37, 95% confidence interval: 1.14-4.91, p = 0.021). Besides, IL-18 displayed a nonlinear association with adverse clinical events (p nonlinear = 0.044). Subgroup analysis revealed that the correlation between IL-18 and the risk of adverse clinical events was not significantly affected by factors such as age, sex, history of diabetes, smoking, Gensini score, or ACS type (all p interaction >0.05). Conclusion: IL-18 appears to hold potential as a predictive marker for anticipating clinical outcomes in patients with ACS.