Associations between delirium and SARS-CoV-2 pandemic visitor restrictions among hospitalized patients.

Objectives: Delirium is associated with increased morbidity and mortality, but environmental and behavioral factors may decrease the risk of developing delirium and thus must be considered. To investigate trends in delirium prevalence and examine associations of visitor restrictions with delirium diagnoses among all patients hospitalized during and prior to the novel coronavirus SARS-CoV-2 (COVID-19) pandemic.

Study Design: Retrospective epidemiological assessment.

Methods: The medical records of all patients (n = 33,141) hospitalized within a three-hospital academic medical center system in a large Midwestern metropolitan area from March 20, 2019, through March 19, 2021, were analyzed.

Results: The overall prevalence of delirium during COVID-19 was 11.26% (confidence interval [CI]: 10.79%, 11.73%) compared to 9.28% (CI: 8.82%, 9.73%) before COVID-19. From our adjusted logistic regression analyses, we observed that the odds of delirium among non-isolated patients were significantly higher during COVID-19 visitor restrictions (adjusted odds ratio [aOR]: 1.354; 95% CI: 1.233, 1.488; P < 0.0001) than before. The odds of delirium among isolated patients were not significantly higher during COVID-19 visitor restrictions (aOR: 1.145; 95% CI: 0.974, 1.346; P = 0.1006) than before.

Conclusions: Medically isolated patients remained at high risk of developing delirium both prior to and during COVID-19 era visitor restrictions. However, non-medically isolated patients had a significantly increased risk of delirium during the social isolation of visitor restrictions compared to prior to visitor restrictions.