Abstract
BACKGROUND: While both the systemic immune-inflammation index (SII) and prognostic nutritional index (PNI) have demonstrated prognostic value in various diseases, the clinical utility of their combined score (SII-PNI) for predicting outcomes in patients with severe community-acquired pneumonia (SCAP) remains incompletely understood. The aim of this study is to explore the predictive value of SII-PNI score in patients with SCAP. METHODS: We conducted a retrospective analysis of the clinical data of 138 patients diagnosed with SCAP. The SII, PNI, and the SNII-PNI score were calculated. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal threshold of SII-PNI. Multivariable logistic regression models were used to assess the association between the SII-PNI score and 28-day mortality. RESULTS: The cutoff values for predicting 28-day mortality were >4689.82 for SII and <32.18 for PNI, respectively, with sensitivities of 59.1% and 60.3% and specificities of 85.3% and 68.2%. Multivariate analysis reveals that a SII-PNI score of 2 (OR, 14.11; 95% CI, 3.18-62.66; p = 0.001) was independently associated with a high risk of 28-day mortality. CONCLUSION: Our results indicate that a higher SII-PNI score at admission was linked to poor prognosis in SCAP patients. The combined SII-PNI score can effectively help clinicians assess disease progression and optimize risk assessment and clinical management for SCAP patients.