Association Between Systemic Inflammatory Indices and Lund–Mackay Score in Chronic Rhinosinusitis with Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous inflammatory disease in which identifying simple biomarkers reflecting disease severity remains challenging. This study aimed to evaluate the relationship between systemic inflammatory indices and radiological disease severity assessed by the Lund–Mackay (LM) score. This retrospective study included 90 adult patients with CRSwNP who underwent endoscopic sinus surgery. Preoperative computed tomography findings were scored using the LM system, and systemic inflammatory indices, including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), eosinophil-to-lymphocyte ratio (ELR), neutrophil-to-monocyte ratio (NMR), systemic immune-inflammatory index (SII), systemic inflammation response index (SIRI), and eosinophil/leukocyte ratio, were calculated from complete blood count parameters. Spearman correlation and univariate logistic regression analyses were performed. ELR (r = 0.49, p < 0.001) and eosinophil/leukocyte ratio (r = 0.46, p < 0.001) showed moderate positive correlations with LM score, whereas other indices were not significantly associated. In logistic regression analysis, both ELR (OR = 5.44 × 104, p < 0.001) and eosinophil/leukocyte ratio (OR = 4.99 × 1012, p = 0.001) were significantly associated with high disease burden (LM ≥ 15). These findings suggest that eosinophil-based inflammatory indices may better reflect radiological disease severity in CRSwNP compared to traditional systemic inflammatory markers.