Relationship between preoperative estimated glomerular filtration rate and postoperative delirium / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the relationship between preoperative estimated glomerular filtration rate (eGFR) and postoperative delirium (POD) in the patients.Methods:Six hundred and twenty-five patients, aged ≥60 yr, of American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅱ, scheduled for elective total knee and hip arthroplasty under combined spinal-epidural anesthesia, were included. Peripheral blood samples were collected before surgery, and serum creatinine levels were measured by the sarcosine oxidase method, and eGFR was calculated using the MDRD equation. After successful spinal-epidural puncture, cerebrospinal fluid 2 ml was collected for determination of β-amyloid 42 (Aβ42), total tau protein (T-tau) and phosphorylated tau protein (P-tau) by enzyme-linked immunosorbent assay. The patients were divided into POD group and non-POD group (NPOD group) according to the occurrence of POD. The logistic regression analysis was used to identify the risk factors for POD, and the mediating effect of CSF biomarkers was analyzed. The receiver operating characteristic (ROC) curve was drawn to evaluate the accuracy of eGFR and biomarkers in predicting POD.Results:A total of 514 patients were finally enrolled in this study, and the incidence of POD was 16.7%. The logistic regression analysis showed that decreased eGFR and increased levels of P-tau and T-tau in CSF were risk factors for POD, while increased CSF Aβ42 level, Aβ42/P-tau ratio and Aβ42/T-tau ratio were protective factors for POD after adjusting for multiple confounding variables ( P<0.05). Analysis of mediating effet The direct effect of eGFR on POD was -0.0 005 267, the total effect was 0.0 046 446, T-tau had a partly mediating role and the mediating effect accounted for 11.3% of the total effect. The area under the ROC curve of eGFR and CSF biomarker in predicting POD was 0.812( P<0.001). Conclusions:Preoperative decrease in eGFR is a risk factor for POD, and T-tau in CSF serves as a key mediator in the relationship between eGFR and POD.