DEVELOPMENT AND INTERNAL-EXTERNAL VALIDATION OF THE ACCI-SOFA MODEL FOR PREDICTING IN-HOSPITAL MORTALITY OF PATIENTS WITH SEPSIS-3 IN THE ICU: A MULTICENTER RETROSPECTIVE COHORT STUDY

Abstract

Objective: To achieve a better prediction of in-hospital mortality, the Sequential Organ Failure Assessment (SOFA) score needs to be adjusted and combined with comorbidities. This study aims to enhance the prediction of SOFA score for in-hospital mortality in patients with Sepsis-3. Methods: This study adjusted the maximum SOFA score within the first 3 days (Max Day3 SOFA) in relation to in-hospital mortality using logistic regression and incorporated the age-adjusted Charlson Comorbidity Index (aCCI) as a continuous variable to build the age-adjusted Charlson Comorbidity Index-Sequential Organ Failure Assessment (aCCI-SOFA) model. The outcome was in-hospital mortality. We developed, internally validated, and externally validated the aCCI-SOFA model using cohorts of Sepsis-3 patients from the MIMIC-IV, MIMIC-III (CareVue), and the FAHWMU cohort. The predictive performance of the model was assessed through discrimination and calibration, which was assessed using the area under the receiver operating characteristic and calibration curves, respectively. The overall predictive effect was evaluated using the Brier score. Measurements and main results: Compared with the Max Day3 SOFA, the aCCI-SOFA model showed significant improvement in area under the receiver operating characteristic with all cohorts: development cohort (0.81 vs 0.75, P < 0.001), internal validation cohort (0.81 vs 0.76, P < 0.001), MIMIC-III (CareVue) cohort (0.75 vs 0.68, P < 0.001), and FAHWMU cohort (0.72 vs 0.67, P = 0.001). In sensitivity analysis, it was suggested that the application of aCCI-SOFA in early nonseptic shock patients had greater clinical value, with significant differences compared with the original SOFA scores in all cohorts ( P < 0.05). Conclusion: For septic patients in intensive care unit, the aCCI-SOFA model exhibited superior predictive performance. The application of aCCI-SOFA in early nonseptic shock patients had greater clinical value.