Delirium in hospitalized COVID-19 patients: a prospective, multicenter, cohort study

Delirium is a prevalent symptom of acute brain dysfunction caused by Coronavirus disease 2019 (COVID-19). However, the understanding of delirium in COVID-19 patients is currently limited. This study aimed to investigate the prevalence of delirium and its risk factors in hospitalized COVID-19 patients for early identification and management of delirium.

This cohort study included hospitalized patients with SARS-CoV-2 infection at seven tertiary hospitals from January to February 2023. Delirium was assessed at a single time point using the 3-Minute Diagnostic Assessment for Delirium by trained research assistants. Demographic data, clinical characteristics, in-hospital mortality and other variables were collected from health information system. Multivariate regression analyses were conducted to investigate the risk factors for delirium and the impact of delirium on in-hospital mortality.

A total of 4589 COVID-19 patients were included, out of which 651 cases (14.2%) were identified as delirium. In the multivariable analysis, aging (OR 3.58 [95%CI 2.75-4.67], p < 0.001), higher aspartic transaminase/alanine transaminase ratio (OR = 1.11, [95%CI 1.02-1.21], p = 0.018), Mg²⁺ (OR = 3.04, [95%CI 2.56-3.62], p < 0.001), blood urea nitrogen (OR = 1.01, [95%CI 1.00, 1.02], p = 0.024), and indwelling urethral catheterization (OR = 1.59, [95%CI 1.21, 2.09], p < 0.001) were associated with an increased risk of delirium. After adjusting for age, sex, and CCI, delirium was found to be associated with an increased risk of in-hospital mortality (OR = 2.42, [95%CI 1.59, 3.67], p < 0.001).

Delirium was a frequent complication among hospitalized COVID-19 patients and was related to unfavorable outcomes. It is crucial to reduce delirium and its long-term effects by addressing the modifiable risk factors.