Meta-analysis of the incidence and risk factors of postoperative delirium in organ transplant patients.

Background: Postoperative delirium (POD) is a concerning complication of organ transplantation. With organ transplantation offering hope to patients with end-stage organ disease, understanding the incidence and risk factors of POD is crucial, as it can significantly affect patients' prognosis and healthcare costs.

Aim: To systematically evaluate the incidence and risk factors of POD following organ transplantation to facilitate clinical prevention and optimize patient management and prognosis.

Methods: Multiple databases such as PubMed and their reference lists were comprehensively searched using a combination of keywords related to organ transplantation and POD. Relevant observational studies on patients who had undergone solid organ transplantation and randomized controlled trials containing relevant analyses were included. Duplicated, data-deficient, non-English, and non-original data studies were excluded. Data were extracted independently by two researchers and then cross-checked. The Newcastle-Ottawa scale was used to evaluate the quality of the included studies. RevMan 5.3 was employed for data analysis. The pooled incidence of POD was calculated according to the data type, and the fixed or random effect model was employed to analyze risk factors based on heterogeneity. Subsequently, sensitivity analysis and publication bias assessments were performed.

Results: A total of 39 relevant literatures were included. The overall incidence of POD in the organ transplant group was 20% [95% confidence interval (CI): 18%-22%]; liver transplant group, 22% (95%CI: 17%-26%); lung transplant group, 34% (95%CI: 23%-45%); and kidney transplant group, 6% (95%CI: 2%-10%). Primary graft dysfunction increased the POD risk, with a pooled odds ratio (OR) (95%CI) of 1.78 (1.09-2.91). A history of hepatic encephalopathy increased the POD risk, with a pooled OR (95%CI) of 3.19 (2.30-4.43). The higher the Acute Physiology and Chronic Health Evaluation II score, the greater the POD risk, with a pooled OR (95%CI) of 1.52 (1.09-2.12). A history of alcohol abuse increased the POD risk, with a pooled OR (95%CI) of 2.84 (1.74-4.65). Thus, the higher the model for end-stage liver disease score, the greater the POD risk, with a pooled OR (95%CI) of 2.49 (1.14-5.43). POD was more likely to develop in patients with preoperative infections, with a pooled OR (95%CI) of 2.78 (1.56-4.97). The use of diuretics increased the POD risk, with a pooled OR (95%CI) of 2.36 (1.38-4.04).

Conclusion: In this study, the overall incidence of POD in patients who underwent organ transplantation is 20%. The incidence varies among different types of organ transplantation, and multiple factors can increase the POD risk.