Comparative analysis of intensive care unit prognostication scores and their renal components in predicting hospital mortality among critically ill patients

Introduction: Prognostication is essential for risk stratification in the intensive care unit (ICU). The SOFA, APACHE II, and SAPS II scores are widely used severity scoring systems, although their renal components differ. Given the association of acute kidney injury (AKI) with higher morbidity and mortality, this study aimed to evaluate these scoring systems and identify which renal component best predicts ICU outcomes. Such an insight can enhance the precision of risk assessment in critically ill patients. Methods: A retrospective observational cohort study was conducted involving all patients admitted to the ICU of Sultan Ahmad Shah Medical Centre (SASMEC@ICU). SOFA, APACHE II, and SAPS II scores, along with their individual components, were calculated within the first 24 hours of ICU admission. Results: Of the 1,513 patients analysed, 360 (23.8%) died in hospital. The SOFA score had the highest predictive accuracy for hospital mortality with an AUC of 0.78, followed by SAPS II (0.77) and APACHE II (0.72). Optimal cut-off points were identified for practical application. The renal components of the SOFA and SAPS II had similar AUCs of 0.64, while APACHE II’s renal component was lower (0.62). Findings were consistent in the AKI subgroup. Conclusions: The SOFA score outperformed APACHE II and SAPS II in predicting hospital mortality in critically ill patients. The renal components of the SOFA and SAPS II scores were more predictive than the that of APACHE, likely due to the inclusion of urine output criteria. Future multicentre studies using raw patient-level data are needed to develop a robust prognostic model tailored to our local ICU population.