CBC-Derived Biomarkers Associated With Recurrence After Sinus Surgery in Chronic Rhinosinusitis

Recurrence of chronic rhinosinusitis (CRS) after endoscopic sinus surgery (ESS) is common; however, biomarkers for long-term risk stratification remain limited. We examined associations between complete blood count (CBC)-derived biomarkers and long-term CRS recurrence after ESS.

A retrospective cohort of 543 CRS patients undergoing ESS was analyzed using time-to-event methods. Prespecified variables comprised CBC-derived biomarkers: absolute eosinophil count (AEC); eosinophil-to-lymphocyte, -monocyte, and -neutrophil ratios; monocyte-, neutrophil-, basophil-, and platelet-to-lymphocyte ratios; systemic immune-inflammation index (SII); systemic inflammation response index; and red cell distribution width, together with prespecified clinical covariates. Variable selection was performed using LASSO-penalized Cox regression with multicollinearity screening, followed by multivariable Cox modeling to estimate adjusted hazard ratios (HRs). Incremental prognostic value and longitudinal patterns were assessed.

A total of 254 patients (46.8%) developed recurrence. In the multivariable model, higher AEC (HR: 2.868) and SII (HR: 1.320) were associated with recurrence, along with shorter symptom duration, asthma, NSAID hypersensitivity, nasal polyps, and higher Lund-Mackay scores. Addition of AEC improved model discrimination (C-index 0.778-0.797; ΔC = 0.019; p < 0.001), whereas SII provided minimal additional value (C-index 0.797-0.798; ΔC = 0.001; p = 0.513). In longitudinal analyses, baseline AEC and SII were associated with recurrence, but their changes over time did not differ between groups, with no significant temporal trends.

Higher AEC and SII were independently associated with long-term CRS recurrence after ESS, with AEC providing greater incremental prognostic value than SII. These markers may reflect underlying host predisposition rather than dynamic disease activity.