Prevalence, determinants, and prognostic significance of delirium in patients with acute heart failure

Background: Delirium is a serious syndrome in critically ill patients. However, the prognostic impact of delirium and its determinants in acute heart failure (AHF) patients have not been fully elucidated. Methods: We examined 611 AHF patients who were admitted to our institution. Delirium was diagnosed based on the Intensive Care Delirium Screening Checklist (ICDSC). Results: Delirium developed in 139 patients (23%) during hospitalization. Patients with delirium had higher incidence of non-cardiovascular death (p = 0.046) and worsening heart failure (p < 0.001) during hospitalization. Among patients who survived at discharge, the incidence of all-cause death, cardiovascular death and non-cardiovascular death after discharge were significantly higher in patients with delirium than those without (log-rank; p < 0.001, p = 0.001, p < 0.001, respectively) during a median follow-up period of 335 days. In multivariable model, the development of delirium was an independent determinant of worsening heart failure during hospitalization (OR: 2.44, 95% CI: 1.27-4.63) and all-cause death after discharge (HR: 2.38, 95% CI: 1.30-4.35). Furthermore, multivariate analysis indicated that history of cerebrovascular disease (OR: 2.13, 95% CI: 1.36-3.35), age (OR: 1.43, 95% CI: 1.15-1.80), log BNP (OR: 1.39, 95% CI: 1.09-1.79), serum albumin (OR: 0.84, 95% CI: 0.76-0.93) and blood glucose levels (OR: 1.03, 95% CI: 1.00-1.06) were independent determinants of delirium. Conclusion: In patients with AHF, the development of delirium was associated with poor clinical outcomes, suggesting the importance of early screening and careful monitoring of delirium in such patients. (C) 2016 Elsevier Ireland Ltd. All rights reserved.