Association Between Dexamethasone and Delirium in Critically ill Patients: A Retrospective Cohort Study of a Large Clinical Database

Abstract

BackgroundDelirium is a common complication in ICU patients, and it can significantly increase the length of hospital stay and cost. Dexamethasone is widely used in various inflammatory diseases and is a glucocorticoid commonly used in critically ill patients. There are no studies on the effect of dexamethasone on the development of delirium in critically ill patients, therefore, this study aimed to confirm the effect of dexamethasone use and the dose on the incidence of delirium and patient prognosis in critically ill patients through a large cohort study.MethodsA retrospective cohort study was conducted using data extracted from the MIMIC III database, and the primary outcome was the development of delirium, using multivariate logistic regression analysis to reveal the relationship between dexamethasone and delirium. Secondary endpoints were in-hospital mortality, total length of stay and length of ICU stay, and the relationship between dexamethasone and prognosis was assessed with Cox proportional hazards models. The Lowess smoothing technique was used to investigate the dose correlation between dexamethasone and outcomes, subgroup analysis was used to account for heterogeneity, and different correction models and propensity matching analysis were used to eliminate potential confounders.ResultsFinally, 38,509 patients were included, and 2,204 (5.7%) used dexamethasone. A significantly higher incidence of delirium (5.0% vs. 3.4%, P < 0.001), increased in-hospital mortality (15.0% vs. 11.3%, P < 0.001), and longer length of stay and ICU stay were observed in patients taking dexamethasone compared with those not taking dexamethasone. Multivariate logistic and Cox regression analyses confirmed that dexamethasone was significantly associated with delirium (adjusted OR = 1.45, 95% CI = 1.08-1.95, P = 0.014) and in-hospital mortality (adjusted HR = 1.19, 95% CI = 1.02-1.40, P = 0.032). The risk of delirium and in-hospital death was lower with dexamethasone less than 10 mg, and subjects with 10-14 mg had the shortest length of hospital stay.ConclusionsThis study demonstrated that the use of dexamethasone in critically ill patients exacerbated the occurrence of delirium, while increasing the risk of in-hospital death and length of stay, and the use of low-dose dexamethasone had a lower risk of delirium and death, which appeared to be safer.