Systemic immune inflammation index is associated with ulcerative plaque in patients with acute ischemic stroke: A single center exploratory study

Abstract Purpose This study explored the correlation between inflammatory markers and ulcerative plaques based on Carotid Doppler Ultrasound (CDU) in individuals with Acute Ischemic Stroke (AIS). Methods A total of 202 cases diagnosed with AIS associated with atherosclerotic plaque (AP) in the carotid artery were enrolled in this research. CDU was used to assess carotid atherosclerotic vulnerability and vulnerability-related component features. The AP was classified into different types based on symmetric features and location. Logistic regression and receiver operating characteristic (ROC) curve were employed to analyze the correlation between inflammatory indexes, the shape and position of AP, the degree of carotid artery stenosis, and the presence of ulcerative plaques. Cut-off values were determined accordingly. Results The Systemic Immune Inflammation index (SII) and high sensitivity CRP (hs-CRP) were independent risk factors for the formation of vulnerable carotid plaques. SII level, type A plaque, plaque above carotid bifurcation, and severe carotid stenosis were independent risk factors for ulcerative plaque. The AUC value of SII in predicting ulcerative plaque was 0.895, the sensitivity, specificity, the best cut-off value was 93.3%, 89.2%, 537.4(10 9 /L), respectively. Conclusion Elevated SII levels at admission were found to be independently associated with the presence of AIS with vulnerable plaque, especially ulcerative plaques. Moreover, plaque ulceration was more likely to form when the area of higher plaque thickness was located in the upstream arterial wall of maximum plaque thickness (WTmax), plaque was above the carotid bifurcation, and severe carotid stenosis, providing new insights into the formation of vulnerable plaques.