Postoperative delirium increases follow-up mortality following hip arthroplasty in older patients with femoral neck fracture.

Objective: This study aimed to identify independent perioperative risk factors and follow-up mortality associated with postoperative delirium in older patients undergoing hip arthroplasty at a large teaching hospital in South China. We aimed to establish a specialised model to predict the risk of postoperative delirium.

Methods: This retrospective observational study was conducted in the orthopaedics department of the hospital between January 2018 and December 2022. Participants were stratified into two groups: those with and those without postoperative delirium. The study included demographics, clinical characteristics, surgery-related and laboratory specifics, as well as details on delirium.

Results: In this study of 241 participants, the median age was 80 years (IQR, 74.5-85), with postoperative delirium observed in 43 individuals (18%). Multivariate logistic regression analysis identified age (OR, 1.07; 95% CI, 1.01-1.14; p = .03), arrhythmia (OR, 7.97; 95% CI, 2.25-28.29; p = .001), dementia (OR, 7.08; 95% CI, 1.73-28.95; p = .006) and a lower level of red blood cells (RBC) (OR, .33; 95% CI, .17-.64; p < .001) as independent factors associated with postoperative delirium after hip arthroplasty. Patients experiencing both preoperative and postoperative delirium had significantly higher follow-up mortality compared to those with postoperative delirium only and those without delirium (80% vs. 38% vs. 24%, p = .02).

Conclusions: The specialised model was established to effectively predict delirium following hip arthroplasty in patients with femoral neck fracture. Postoperative delirium strongly associates with follow-up mortality. Proactive management is crucial for minimising delirium occurrence after hip arthroplasty and improving patient outcomes.