Delirium clouds survival outlook in older COVID-19 patients

Delirium is a common occurrence among older adults hospitalized for the novel coronavirus disease (COVID-19), a recent study has found. In turn, delirium seems to worsen mortality risk.

Researchers conducted a multicentre observational cohort study of 516 COVID-19 patients (median age, 78 years; 62 percent male). Delirium on admission was identified using the Diagnostic and Statistical Manual of Mental Disorders, modified Richmond Agitation Sedation Scale, the 4 A’s Test (4-AT), or a physician’s clinical impression.

Seventy-three patients were found to have delirium upon admission, resulting in a prevalence rate of 14.1 percent. These patients were, on average, 7 years older than the no-delirium comparators, were on more prescription medication, and had a greater number of pre-existing diseases.

Multivariable regression analysis identified dementia, having more chronic diseases, and opacities on chest x-ray or computed tomography as significant correlates for delirium.

Over a median follow-up of 19 days, 37 percent (n=191) of the patients died, 278 were discharged to their homes, and 47 were transferred to other care centres of lower-intensity wards. At 30 days from admission, 38 and 145 patients in the delirium and comparator groups died, respectively. The corresponding rates were 53.2 percent and 33.8 percent (p<0.001).

At the same time point, 24.2 percent and 50.1 percent of the patients in the respective groups were discharged from the hospital.

Fully adjusted Cox regression analysis showed that delirium doubled the risk of in-hospital mortality (hazard ratio, 2.00, 95 percent confidence interval, 1.23–3.25).