[Correlation between the systemic immune-inflammation index and carotid atherosclerosis: A cross-sectional study based on a health examination population].

OBJECTIVES: Carotid atherosclerosis (CAS) plaques are independent risk factors for stroke, and chronic vascular inflammation is involved in their pathogenesis. This study aims to explore the association between the systemic immune-inflammation index (SII) and CAS, analyze sex-specific differences in this association, and provide evidence for the early prevention and control of atherosclerosis. METHODS: This single-center cross-sectional study included adults who underwent health examinations and completed carotid ultrasound assessments at Xiangya Hospital of Central South University between January and December 2023, among whom those with CAS were classified as a CAS group, and those without CAS were classified as a normal control group. Demographic characteristics, anthropometric measurements, and laboratory data were collected. Participants were categorized into Quartile 1 to 4 based on SII . Four binary logistic regression models were constructed to progressively adjust for confounders and evaluate the association between SII and CAS, with further stratification by sex. Mediation analyses stratified by sex. Mediation analyses stratified by sex were performed using the Bootstrap method (5 000 resamplings), with white blood cell and monocyte counts as mediators. Sensitivity analyses were conducted to verify robustness. RESULTS: