Inpatient Rehabilitation Delirium Screening: Impact on Acute Care Transfers and Functional Outcomes

Background: Delirium is well studied in the acute care setting, but there is limited understanding of its impact in the postacute care setting, particularly in the inpatient rehabilitation facility (IRF). Objective: To investigate the prevalence and related outcomes of delirium in the IRF setting, particularly patients' transfers to acute care hospitals. Design: Retrospective cohort study. Setting: A freestanding IRF. Participants: Patients discharged from an IRF between January 2016 and December 2016 (12 months). Interventions: Not applicable. Main Outcome Measures: Transfer to acute care hospitals, motor and cognitive Functional Independence Measures (FIM), length of stay, discharge disposition. Results: A total of 1567 patients (53.9% female, mean age 72.9 ± 13.9) were included in the analysis. Positive scores were found among 142 (9.1%) patients on a 3-Minute Diagnostic Interview for Confusion Assessment Method (3D-CAM), indicating delirium on admission. Fifty-nine (3.8%) were unscorable on 3D-CAM. Twice as many delirium patients were transferred to acute care hospitals compared to non-delirium patients (22.5% vs. 10.8%, P <.001). Multivariate logistic regression showed that, for patients with 3D-CAM positive scores, there was an increased risk of transfers to acute care hospitals at an odds ratio of 1.61 (1.03-2.53, P =.04) after adjusting for age, gender, neurological diagnosis, and motor FIM score. The delirium group also showed lower gains in motor function, increased lengths of stay, and reduced discharges to home when compared to the non-delirium group (P <.001). Conclusions: This study finds that delirium on admission to an IRF is associated with worsened outcomes related to function, length of stay, discharge status, and transfer to acute care hospitals. Positive delirium screening is an independent predictor for transfer to acute care hospitals from an IRF. Early identification of delirium is recommended in order to mitigate preventable transfers.