Delirium in the Acute Phase of Ischemic Stroke: Incidence, Risk Factors, and Effects on Functional Outcome

Objective: The aim of this prospective cohort study was to assess the incidence and risk factors of delirium following acute ischemic stroke, as well as its effects on functional outcome. Methods: Two hundred and sixty-one patients with acute ischemic stroke were screened for delirium during the first week after admission. Delirium was diagnosed according to the Confusion Assessment Method. If delirium was present, delirium rating scale-revised-98 was used to assess its severity. Neurologic deficits were assessed with the National Institutes of Health Stroke Scale (NIHSS). Brain magnetic resonance imaging assessment quantified the infarction, white matter lesions, and medial temporal lobe atrophy. Functional outcome assessment included the modified Rankin Scale and Lawton Instrumental Activities of Daily Living scale at 3 and 6 months after the index stroke. Results: Thirty-eight (14.6%) patients with acute ischemic stroke developed delirium during the first week of admission. Patients with poststroke delirium (PSD) were older, had higher NIHSS scores on admission, and were more likely to have a previous stroke, an infection, and a left cortical infarct. Furthermore, left cortical infarction, older age, severer neurological deficit and having a previous stroke increased the risk of PSD. PSD was associated with a worse functional outcome. Conclusion: The incidence of delirium was 14.8% in the first week after admission with acute ischemic stroke. Age, having a previous stroke, stroke severity, and left-cortical infarction were independently predictors of PSD. PSD may result in a significantly worse functional outcome.