Predictive Value of Pan-Immune-Inflammation Value for Recurrence of Chronic Subdural Hematoma after Burr Hole Drainage

Objective: The Pan-Immune-Inflammation Value (PIV) is a novel composite biomarker that reflects systemic inflammatory status. This study aimed to assess the prognostic value of preoperative PIV in predicting recurrence after burr hole drainage (BHD) in patients with chronic subdural hematoma (CSDH). Methods: We conducted a retrospective analysis of 521 patients who underwent BHD for CSDH between January 2015 and October 2025. Preoperative inflammatory markers, including PIV, the systemic Immune-Inflammation Index (SII), and the systemic Inflammation Response Index (SIRI), were calculated. We performed receiver operating characteristic (ROC) curve analysis and multivariate logistic regression to identify predictive factors for recurrence after BHD. Results: Recurrence was observed in 123 patients (23.6%). The recurrence group had a significantly higher mean PIV value compared to the non-recurrence group (481.8 ± 211.2 vs. 259.4 ± 164.7, p = 0.020). ROC analysis showed that PIV had the highest predictive accuracy for recurrence, with an area under the curve of 0.801 (95% confidence interval [CI] 0.753-0.850; p < 0.001). The optimal cutoff value for PIV to predict recurrence after BHD was determined to be 311.4. In multivariate analysis, elevated SII (≥ 551.2) (odds ratio [OR] 1.12, 95% CI 1.06-1.38; p = 0.048) and elevated PIV (≥ 311.4) (OR 1.28, 95% CI 1.08-1.86; p = 0.022) were identified as independent predictors of recurrence after BHD. Conclusion: Preoperative PIV is a strong, independent predictor of CSDH recurrence following BHD. Further research is needed to validate the prognostic role of PIV in patients with CSDH.