Postoperative Serum Albumin Decrease Independently Predicts Delirium in the Elderly Subjects after Total Joint Arthroplasty

Background: Postoperative delirium (POD), a neurobehavioral syndrome induced by dysfunction of neural activity, is a common and serious complication. This current study aimed to investigate independent predictors for POD in elderly subjects after total joint arthroplasty (TJA). Methods: Eligible elderly patients (≥65 years) who underwent elective unilateral primary hip or knee arthroplasty under epidural anesthesia from October 2016 to January 2019 were consecutively enrolled. POD was diagnosed following the guidance of the 5th edition of Diagnostic and Statistical Manual of Mental Disorders, (DSM V, 2013). The relative change in serum Alb (ΔAlb) was defined as the absolute value of (preoperative Alb value– nadir value within postoperative day 2)/preoperative Alb x100%. The predictive value of ΔAlb for POD was evaluated by receiver operating characteristic (ROC) curve analysis. Univariate and multivariate logistic regression analyses were used for evaluating risk factors for POD. Results: A total of 328 patients were enrolled in the analysis, of which 68 (20.7%, 68/328) patients developed POD within postoperative 7 days. ΔAlb was an effective predictor for POD with an area under the curve (AUC) of 0.821, a sensitivity of 76.15% and a specificity of 70.59%, respectively (P<0.001). Univariate and multivariate logistic regression analyses indicated that ΔAlb was the only independent risk factor for POD (OR: 2.43, 95%CI: 1.17–4.86, P=0.015). Conclusion: ΔAlb was an independent risk factor for POD in elderly subjects after TJA.