Impact of delirium on the outcome of stroke: a prospective, observational, cohort study

INTRODUCTION: Delirium is an acute fluctuating disorder of attention and awareness, which often complicates the clinical course of several conditions, including acute stroke. The aim of the present study was to determine whether delirium occurrence impacts the outcome of patients with acute stroke. METHODS: The study design is single center, prospective, observational. We consecutively enrolled patients admitted to the stroke unit from April to October 2020. Inclusion criteria were age ≥ 18 years and diagnosis of acute stroke. Exclusion criteria were stroke mimics, coma, and terminal conditions. All patients were screened for delirium upon admission, within 72 h, and whenever symptoms suggesting delirium occurred by means of the Confusion Assessment Method for Intensive Care Unit and the Richmond Agitation Sedation Scale. Outcomes were evaluated with the 90-days modified Rankin Scale (mRS) by telephone interview. RESULTS: The final study cohort consisted of 103 patients (62 men; median age 75 years, interquartile range 63–81). Thirty-one patients (30%) developed delirium. In the multivariate ordinal logistic regression, patients with delirium had higher mRS scores at 3 months (DLR + : mRS = 4 (3–6); DLR–: mRS = 1 (1–3); adjusted odds ratio = 4.83; CI = 1.88–12.35; p = 0.006). Delirium was a risk factor for death (mRS = 6) in the univariate logistic regression (OR 4.5, CI = 1.44–14.07; p = 0.010), but not in the adjusted analysis (OR 3.45; CI = 0.66–17.95; p = 0.142). Survival time during 90-days follow-up was shorter in the delirium group (Log Rank χ(2) 3.89; p = 0.048). CONCLUSION: Delirium negatively impacts the prognosis of patients with acute stroke. Patients with post-stroke delirium have a worse functional outcome and a shorter survival.