Association of preoperative frailty with risk of postoperative delirium in older patients undergoing craniotomy: a prospective cohort study.

Background: Preoperative frailty is a risk factor associated with postoperative delirium (POD), which has attracted more attention from clinicians, but no research has shown that it is related to elderly patients undergoing craniotomy. Therefore, the aim of this study was to determine the effect of preoperative frailty on POD in older patients, especially those who underwent craniotomy.

Methods: From October 2022 to May 2023, older patients who underwent elective craniotomy were collected. Assess the occurrence of frailty using the FRAIL scale one day before surgery. Evaluate the occurrence of POD using the Confusion Assessment Method (CAM) within three days after surgery. Participants were divided into two groups, one group being POD, Logistic regression analysis was used to find the risk variables for POD, and the predictive value of preoperative frailty to POD was determined by using the operating characteristic curve of the subjects.

Results: A total of 300 patients were included in this study, among whom 83 patients (27.7%) exhibited preoperative frailty and 69 patients (23.0%) experienced POD. The results of the multivariate logistic regression analysis indicate that preoperative frailty (OR: 8.816, 95% CI: 3.972-19.572), preoperative hypoalbuminemia (OR: 0.893, 95% CI: 0.811-0.984), low BMI (OR: 0.793, 95% CI: 0.698-0.901), and prolonged operative duration (OR: 1.007, 95% CI: 1.004-1.010) are independent risk factors for POD in older patients who underwent craniotomy. We constructed a risk prediction model using these factors, which had an area under the ROC curve of 0.908 (95% CI: 0.869-0.947, P < 0.001). Preoperative frailty enhanced the discriminative ability of the prediction model by 0.037. POD was associated with a longer length of hospital stay and higher hospitalization costs.

Conclusions: Preoperative frailty is an independent risk factor for POD in older patients undergoing elective craniotomy and can predict the occurrence of POD to a certain extent. In addition, early identification of patients at risk of malnutrition and appropriate surgical planning can reduce the incidence of POD.