Impact of Delirium and Its Motor Subtypes on Stroke Outcomes

Delirium is an acute and fluctuating impairment of attention, cognition, and behavior. Although common in stroke, studies that associate the clinical subtypes of delirium with functional outcome and death are lacking. We aimed to evaluate the influence of delirium occurrence and its different motor subtypes over stroke patients' prognosis.

Prospective cohort of stroke patients with symptom onset within 72 hours before research admission. Delirium was diagnosed by Confusion Assessment Method for the Intensive Care Unit, and its motor subtypes were defined according to the Richmond Agitation-Sedation Scale. The main outcome was functional dependence or death (modified Rankin Scale>2) at 90 days comparing: delirium versus no delirium patients; and between motor subtypes. Secondary outcomes included modified Rankin Scale score >2 at 30 days and 90-day-mortality.

Two hundred twenty-seven patients were enrolled. Delirium occurred in 71 patients (31.3%), with the hypoactive subtype as the most frequent, in 41 subjects (57.8%). Delirium was associated with increased risk of death and functional dependence at 30 and 90 days and higher 90-day mortality. Multivariate analysis showed delirium (odds ratio, 3.28 [95% CI, 1.17-9.22]) as independent predictor of modified Rankin Scale >2 at 90 days.

Delirium is frequent in stroke patients in the acute phase. Its occurrence-specifically in mixed and hypoactive subtypes-seems to predict worse outcomes in this population. To our knowledge, this is the first study to prospectively investigate differences between delirium motor subtypes over functional outcome three months poststroke. Larger studies are needed to elucidate the relationship between motor subtypes of delirium and functional outcomes in the context of acute stroke.