Economic Impact of Poststroke Delirium and Associated Risk Factors Findings From a Prospective Cohort Study

Background and Purpose: Delirium is a common severe complication of stroke. We aimed to determine the cost-of-illness and risk factors of poststroke delirium (PSD). Methods: This prospective single-center study included n=567 patients with acute stroke from a hospital-wide delirium cohort study and the Swiss Stroke Registry in 2014. Delirium was determined by Delirium Observation Screening Scale or Intensive Care Delirium Screening Checklist 3 times daily during the first 3 days of admission. Costs reflected the case-mix index and diagnosis-related groups from 2014 and were divided into nursing, physician, and total costs. Factors associated with PSD were assessed with multiple regression analysis. Partial correlations and quantile regression were performed to assess costs and other factors associated with PSD. Results: The incidence of PSD was 39.0% (221/567). Patients with delirium were older than non-PSD (median 76 versus 70 years; P<0.001), 52% male (115/221) versus 62% non-PSD (214/346) and hospitalized longer (mean 11.5 versus 9.3 days; P<0.001). Dementia was the most relevant predisposing factor for PSD (odds ratio, 16.02 [2.83-90.69], P=0.002). Moderate to severe stroke (National Institutes of Health Stroke Scale score 16-20) was the most relevant precipitating factor (odds ratio, 36.10 [8.15-159.79], P<0.001). PSD was a strong predictor for 3-month mortality (odds ratio, 15.11 [3.33-68.53], P<0.001). Nursing and total costs were nearly twice as high in PSD (P<0.001). There was a positive correlation between total costs and admission National Institutes of Health Stroke Scale (correlation coefficient, 0.491; P<0.001) and length of stay (correlation coefficient, 0.787; P<0.001) in all patients. Quantile regression revealed rising nursing and total costs associated with PSD, higher National Institutes of Health Stroke Scale, and longer hospital stay (all P<0.05). Conclusions: PSD was associated with greater stroke severity, prolonged hospitalization, and increased nursing and total costs. In patients with severe stroke, dementia, or seizures, PSD is anticipated, and additional costs are associated with hospitalization.