Delirium During COVID Hospitalization Raises Disability, Cognitive Risks

Older adults who experienced delirium while hospitalized for COVID-19 had increases in functional disability and cognitive impairment in the 6 months after discharge, according to a prospective cohort study.

Among older patients hospitalized for COVID-19 early in the pandemic, those with delirium had increased functional disability (rate ratio 1.32, 95% CI 1.05-1.66) and cognitive impairment (odds ratio 2.48, 95% CI 1.38-4.82) over the 6 months after discharge compared with those without in-hospital delirium, reported Lauren Ferrante, MD, MHS, of Yale University in New Haven, Connecticut, and colleagues in JAMA Network Open.

Of the 311 people in the functional disability sample (the full cohort), 15.8% had in-hospital delirium. In the cognition sample of 271 patients, 11.4% experienced in-hospital delirium.

“Older adults continue to be hospitalized with COVID-19 throughout the year, and many experience delirium during that hospitalization, yet they are not routinely screened for functional and cognitive impairment after discharge,” Ferrante told MedPage Today in an email.

“Older survivors of a COVID hospitalization who experience in-hospital delirium should be evaluated for functional and cognitive impairment soon after discharge, and referred for physical and cognitive rehabilitation early,” Ferrante emphasized.

Of patients with in-hospital delirium, the unadjusted mean disability count increased from 4 disabilities before hospitalization to 6.6 disabilities at 1 month after discharge, and then decreased to 5.3 disabilities at 6 months postdischarge. In those without in-hospital delirium, the mean number of disabilities before hospitalization was 1.8, increasing to 2.7 at 1 month after discharge, and decreasing to 2.1 disabilities at 6 months.

Among patients who developed in-hospital delirium, 9.7% had cognitive impairment before hospitalization versus 2.9% of those without delirium. At 6 months, the percentage of those with cognitive impairment increased to 34.8% in the group with delirium versus 20.7% in those without delirium.

The study is not the first to find a link between delirium during COVID-19 hospitalization and poor outcomes. A Brazilian study found that cognitive impairment was associated with higher age, less education, and delirium after hospitalization in 2020 with severe COVID.

“Many established delirium prevention efforts were disrupted during the height of the pandemic,” Ferrante commented. Even now, delirium prevention protocols are not always fully implemented for COVID patients, she noted.

“Our study calls for a renewed focus on delirium prevention efforts,” she said. This includes family engagement, early mobilization, treating hearing and vision impairment, frequent orientation, nonpharmacologic sleep preservation protocols, and avoiding sedating medications known to precipitate delirium.

The research included 311 adults ages 60 and older who were hospitalized for COVID-19 from June 2020 through June 2021 at five major tertiary hospitals in the U.S. The mean age was about 71 years and 52.4% were female. More than one-third were patients from minority racial and ethnic groups. Of the 311 participants, only 271 were included in the cognition sample due to missing data.

Researchers evaluated disability using basic activities and instrumental activities of daily living, and three mobility activities. The Montreal Cognitive Assessment 5-minute protocol was used to assess cognition. All assessments took place 1, 3, and 6 months after being discharged from the hospital.

One limitation of the study is that researchers relied on electronic medical records to determine baseline cognitive impairment rather than clinical assessment, so some cases may have been missed. The cohort may have not included the most critically ill patients, resulting in a bias towards a healthier population. Patients were enrolled before the widespread use of COVID-19 vaccines; it’s unclear how vaccination might influence outcomes, the authors noted.