Comparison of serum IL-18, IL-1β and caspase-1 levels in patients with chronic venous insufficiency and coronary artery bypass grafting

Aim: Chronic venous insufficiency (CVI) and coronary artery disease requiring coronary artery bypass grafting (CABG) are both associated with systemic inflammation. Inflammasome-mediated pathways involving caspase-1, interleukin-1Beta (IL-1β), and interleukin-18 (IL-18) contribute to vascular inflammation. This study compared circulating inflammasome-related biomarkers and hematological inflammatory indices between patients with CVI and CABG.

Material and Methods: This prospective observational study included 40 patients (20 with CVI and 20 undergoing elective CABG). Serum IL-18, IL-1β, and caspase-1 concentrations were measured using enzyme-linked immunosorbent assay (ELISA). Hematological inflammatory indices, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII), were calculated from complete blood counts. Group comparisons were performed using the Mann–Whitney U test, correlations using Spearman’s rank correlation analysis, and adjusted analyses using analysis of covariance (ANCOVA) controlling for age and sex.

Results: In the unadjusted analyses, serum IL-18, IL-1β, and caspase-1 levels were significantly higher in the CABG group than in the CVI group (all p < 0.05). Neutrophil count, NLR, and SII were also significantly higher in CABG patients, whereas platelet counts were higher in the CVI group. The SII showed a positive correlation with IL-18 in the CABG group (r = 0.655, p = 0.021). After adjustment for age and sex, only serum caspase-1 remained independently associated with the study group, whereas differences in IL-1β and IL-18 were no longer statistically significant.

Conclusion: Although CABG patients exhibited greater inflammasome-related inflammatory activity than CVI patients in unadjusted analyses, only serum caspase-1 remained independently associated with disease status after adjustment for demographic variables. Caspase-1 may, therefore, represent a more robust biomarker of inflammasome activation in advanced coronary artery disease.