Course and Recognition of Poststroke Delirium: A Prospective Noninferiority Trial of Delirium Screening Tools.

BACKGROUND AND PURPOSE

Poststroke delirium (PSD) is an independent predictor of unfavorable outcome. Despite its individual and socioeconomic burden, its frequency, clinical course, and routine detection remain unresolved. This study aimed to assess psychometric properties of established delirium screening tools and investigate the natural course of PSD.

METHODS

This study investigated patients presenting with high-risk transient ischemic attacks or ischemic stroke within 24 hours during a 3-month period. Twice-daily screenings for PSD were done using the confusion assessment method, nursing delirium scale, and rapid delirium assessment, and evaluated for noninferiority against Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria. We investigated demographic and stroke characteristics as predictors of PSD, neurological deficits as predictors of false screening results, and conducted a simulation study to estimate the best timing to identify PSD.

RESULTS

We enrolled 141 patients (73.8±10.4 years of age, 61 female) with a mean National Institutes of Health Stroke Scale score of 6.4±6.5. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition based PSD incidence was 39%, which manifested within 24 hours in 25% and 72 hours in almost all cases. The confusion assessment method was the only screening tool noninferior to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition ratings providing a sensitivity of 82% and specificity of 80%. Age (odds ratio, 1.07 [1.02-1.13] per year, =0.004) and National Institutes of Health Stroke Scale (odds ratio, 1.24 [1.15-1.34] per point, <0.001) were predictors of PSD. False-positive screening results were associated with stroke-induced disorientation (odds ratio, 6.1 [3.2-11.61], <0.001) and neglect (odds ratio, 2.17 [1.22-3.87], =0.008). Simulations revealed that one in 4 cases is missed with less than daily screenings.

CONCLUSIONS

PSD is a common complication of stroke and transient ischemic attack. Detection is challenged by confounding effects such as focal neurological deficits and the necessity for at least daily screenings. Future studies are required to investigate implementation of these findings in clinical routine. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03930719.