Validation of PREdiction of DELIRium in ICu patients (PRE‐DELIRIC) among patients in intensive care units: A retrospective cohort study

BACKGROUND: An intensive care unit (ICU) delirium prediction tool, PREdiction of DELIRium in ICu patients (PRE-DELIRIC), has been developed and calibrated in a multinational project. However, there is a lack of evidence regarding the predictive ability of the PRE-DELIRIC among Chinese ICU patients. AIM: To evaluate the predictive validity (discrimination and calibration) of PRE-DELIRIC. DESIGN: This is a retrospective cohort study. METHODS: A retrospective cohort study was conducted. Consecutive participants (a) admitted to the ICU for ≥24 hours, (b) aged ≥18 years, and (c) admitted to the ICU for the first time were included. Ten predictors (age, APACHE-II, urgent and admission category, urea level, metabolic acidosis, infection, coma, sedation, and morphine use) assessed within 24 hours upon ICU admission were assessed. Delirium was assessed using the Confusion Assessment Method for ICU. Outcomes included ICU length of stay and mortality. Discrimination and calibration were determined by the areas under the receiver operating characteristic curve (AUROC), box plot, and calibration plot. RESULTS: A total of 375 ICU patients were included, with 44.0% of patients being delirious. Delirium was significantly associated with age, PRE-DELIRIC score, ICU length of stay, and mortality. The AUROC was 0.81 (95% confidence interval, 0.77-0.86). The optimal cut-off point identified by max Youden index was 49%. The calibration plot of pooled data demonstrated a calibration slope of 0.894 and an intercept of -0.178. CONCLUSIONS: The PRE-DELIRIC has high predictive value and is suggested to be adopted in ICUs for early initiation of preventive interventions against delirium among high-risk patients. RELEVANCE TO CLINICAL PRACTICE: Clinicians can adopt the PRE-DELIRIC among ICU patients to screen patients at high risk of developing delirium. Early initiative interventions could be implemented to reduce the negative impacts of ICU delirium.