Association between alcohol use disorder and the incidence of delirium in the intensive care unit: a retrospective cohort study using propensity score matching

Background: Although alcohol consumption is considered one of the risk factors for delirium in intensive care unit (ICU) patients, quantitative research on the association between alcohol use disorder (AUD) and the development of delirium in the ICU remains relatively scarce.

Methods: This retrospective cohort study was conducted using the Medical Information Mart for Intensive Care-IV database, including all patients admitted to the ICU for the first time and underwent delirium assessment. Patients were divided into AUD and non-AUD groups, with the primary outcome being the occurrence of ICU delirium. Propensity score matching (PSM) was used to balance baseline characteristics between the two groups. The association between AUD and the occurrence of ICU delirium was evaluated using Cox proportional hazards and competing risk models, with sensitivity and subgroup analyses to assess the stability of the results.

Results: A total of 35,053 patients were included, with 3,455 (9.9%) in the AUD group. The incidence of ICU delirium and ICU mortality were significantly higher in the AUD group compared to the non-AUD group, with a longer median ICU stay. Multivariable Cox regression analysis, adjusting for all covariates, revealed a significant association between AUD and increased risk of ICU delirium (HR 1.59, 95% CI 1.50-1.69, P < 0.01). After PSM, multivariable Cox regression analysis showed consistent results (HR 1.52, 95% CI 1.41-1.65, P < 0.01), and these results remained consistent after performing competitive risk analysis.

Conclusions: We found a significant correlation between AUD and the incidence of delirium in the ICU, highlighting the importance of assessing and managing the risk of delirium in patients with AUD in the ICU.

Clinical trial number: Not applicable.