Association between the unaccompanied nursing care model and postoperative delirium in older adults with hip fractures: a retrospective before-and-after cohort study.

Background: Reduced family participation and restricted visitation have been shown to increase the risk of delirium in older adults. The unaccompanied nursing care model (UNCM), characterized by limited family participation and reduced visitation frequency, differs from the traditional accompanied nursing care model (TNCM), which allows greater family participation. However, clear evidence is lacking regarding whether UNCM, compared with TNCM, is associated with an increased incidence of postoperative delirium (POD) in older adults with hip fractures. Therefore, this study aimed to investigate the potential association between UNCM and POD in this population. Methods: This retrospective cohort study analyzed the medical records of patients who underwent hip fractures surgery at a tertiary medical center between January 2022 and December 2025. Patients were divided into TNCM and UNCM groups according to the UNCM implementation date at this institution (1 July 2024). Propensity score matching (PSM) was performed to balance baseline characteristics between the groups. A 1.59:1 matching approach with a caliper width of 0.2 was used to reduce confounding bias. Covariate balance was evaluated using standardized mean differences (SMDs). A multivariable logistic regression analysis was conducted to examine the independent association between UNCM and POD. Subgroup analyses and interaction tests were performed to explore the potential effect of modification. Results: A total of 645 patients were enrolled, with an overall POD incidence of 14.42%. The POD incidence was 13.9% in the TNCM group and 15.29% in the UNCM group, with no significant difference between the groups ( Conclusion: UNCM may not increase the occurrence of POD in older adults with hip fractures and limited family participation.