Relationship between severity of preoperative brain injury and postoperative delirium in elderly patients: a latent class analysis of markers of brain injury / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the relationship between the severity of preoperative brain injury and postoperative delirium (POD) in elderly patients using latent class analysis based on markers of brain injury.Methods:One hundred and thirty-one American Society of Anesthesiologists Physical Status classification Ⅰ-Ⅲ patients, aged 65-84 yr, with a body mass index of 18-28 kg/m 2, scheduled for elective unilateral total hip arthroplasty in our hospital, were selected. Cognitive function was assessed using the Mini-Mental State Examination before surgery. Arterial blood samples were collected before anesthesia to measure the plasma concentrations of brain-derived neurotrophic factor, inducible nitric oxide synthase, prostaglandin E2, central nervous system-specific protein (S100β), glial fibrillary acidic protein, neurofilament light chain, matrix metalloproteinase-9, fibroblast growth factor 23, complement 3, complement 3a, complement 5a and irisin using enzyme-linked immunosorbent assay. POD was evaluated using the Confusion Assessment Method within 3 days after operation, and the patients were divided into POD group and non-POD group. The patients were divided into different injury severity subtypes based on the levels of brain injury markers using latent class analysis, and logistic multivariate regression was used to analyze the independent risk factors for POD. Results:Compared with non-POD group, the concentrations of neurofilament light chain, glial fibrillary acidic protein, S100β and prostaglandin E2 were significantly different in POD group ( P<0.05). Using these four brain injury markers for latent class analysis, patients were divided into a high severity of brain injury group (91.51%) and a low severity of brain injury group (8.49%). The results of logistic multivariate regression analysis showed that subtypes of brain injury ( OR=8.31, 95% confidence interval [ CI] 1.77-38.90, P=0.007), age ( OR=1.14, 95% CI 1.03-1.24, P=0.007), and plasma irisin concentrations ( OR=0.99, 95% CI 0.98-0.99, P=0.027) were independent risk factors for POD. Conclusions:Higher severity of preoperative brain injury is an independent risk factor for POD in elderly patients.