The Impact of Chronic Kidney Disease on Outcomes in the Intensive Care Unit: Epidemiology and Performance of Common Predictive Scoring Systems

Abstract

Purpose: This thesis investigated outcomes of chronic kidney disease (CKD) patients in the intensive care unit (ICU). Methodology: A systematic review evaluated ICU scoring systems performance in CKD patients, and a cohort study assessed associations between CKD stages and outcomes. Results: The systematic review identified 12 heterogeneous studies. APACHE II/III, SAPS II, and SOFA showed good discrimination in end-stage kidney disease (ESKD) patients on dialysis but consistently overestimated mortality and performed poorly among kidney transplant recipients. The cohort study of 531,090 ICU admissions revealed one quarter had pre-existing CKD. Increasing CKD severity was independently associated with higher mortality and greater risk of kidney replacement therapy (KRT). Dialysis dependent stage 5 CKD showed lower mortality compared to non-dialysis dependent stage 5 CKD. Conclusion: CKD is highly prevalent among ICU patients and strongly associated with mortality and KRT dependence. The scoring systems overestimate mortality risk in this population, highlighting the need for CKD stratification specific studies.