Synthesizing the risk of postoperative delirium in organ transplantation

Abstract

This letter provides a critical appraisal of the comprehensive meta-analysis by Hou et al, which synthesizes the incidence and risk factors for postoperative delirium (POD) in organ transplant recipients. Their work establishes a pooled POD incidence of 20%, with significant variability across organ types (lung 34%, liver 22%, kidney 6%), and identifies key risk factors including primary graft dysfunction, hepatic encephalopathy, and high model for end-stage liver disease/acute physiology and chronic health evaluation II scores. This commentary acknowledges the study's strength in providing a robust, trans-organ synthesis of current evidence. However, it critically discusses the substantial heterogeneity, the counterintuitive non-significance of age as a risk factor, and the unavoidable limitation of unmeasured confounders inherent in meta-analyses, such as preoperative cognitive/psychiatric status and anesthetic protocols. While the findings provide an essential evidence base for risk stratification and prevention, this letter argues that the high heterogeneity underscores the need for organ-specific analysis and calls for large-scale, prospective studies with standardized protocols to translate these findings into reliable clinical prediction tools and targeted interventions.

Keywords: Postoperative delirium; Organ transplant; Risk factors; Statistical heterogeneity; Model for end-stage liver disease/acute physiology and chronic health evaluation II scores

Core Tip: The meta-analysis by Hou et al provides a crucial summary, establishing a 20% overall incidence of postoperative delirium in organ transplant patients, with rates varying significantly by organ. Key risk factors identified, such as primary graft dysfunction and high model for end-stage liver disease/acute physiology and chronic health evaluation II scores, offer actionable targets for clinical prevention. However, the study's substantial heterogeneity and the unexpected non-significance of age as a risk factor highlight the limitations of pooling diverse studies. This commentary emphasizes that while the meta-analysis is a valuable evidence synthesis, its findings should be interpreted with caution, paving the way for future prospective, organ-specific research with standardized protocols to develop robust clinical tools.