Delirium In ICU Patients With Malignancy: Patient Characteristics, Resource Utilization and Outcomes

Abstract

Background: Whereas delirium in the general intensive care unit (ICU) population is common and well studied, knowledge on ICU delirium in patients with malignancy is scarce. The aim was to assess the frequency of delirium and its impact on resource utilizations and outcomes in ICU patients with malignancy.Methods: This retrospective, single-center longitudinal cohort study included all patients with malignancy admitted to ICUs of a University Hospital during one year. Delirium was diagnosed by an Intensive Care Delirium Screening Checklist (ICDSC) score ≥ 4. Groups were compared with Fisher’s exact and Mann-Whitney U tests. Multivariate analysis included binary logistic regression, Cox regression and multiple linear regression. Results are given as number (percentage; confidence interval (CI)) and median (interquartile range).Results: Of 488 ICU patients with malignancy, 176/488 (36%) developed delirium. Frequencies were high in patients with hepatic (13/21 [62%]; 95% CI 41-82%), lung (29/65 [45%]; 95% CI 33-56%) and colorectal malignancies (15/37 [41%]; 95% CI 24-56%). Delirious patients were older (66 [55-72] vs 61 [51-69] years, p = 0.001), had higher SAPS II (41 [27-68] vs 24 [17-32], p < 0.001) and more frequently sepsis (26/176 [15%] vs 6/312 [1.9%], p < 0.001) and / or shock (30/176 [6.1%] vs 6/312 [1.9%], p < 0.001). In multivariate analysis, delirium was independently associated with lower discharge home (OR [95% CI] 0.366 [0.236-0.567], p < 0.001), longer ICU (HR [95% CI] 0.295 [0.234-0.371], p < 0.001) and hospital length of stay (HR [95% CI] 0.619 [0.500-0.765], p < 0.001), longer mechanical ventilation (HR [95% CI] 0.401 [0.282-0.572], p < 0.001), higher ICU nursing workload (B [95% CI] 1.917 [1.665-2.206], p < 0.001) and ICU (B [95% CI] 2.077 [1.811-2.382], p < 0.001) and total costs (B [95% CI] 1.442 [1.301-1.597], p < 0.001). However, delirium was not independently associated with in-hospital mortality (OR [95% CI] 2.263 [0.925-5.537], p = 0.074).Conclusions: In ICU patients with malignancy, delirium was a frequent complication independently associated with high resource utilizations, however, it was not independently associated with in-hospital mortality.

The economic cost of delirium: A systematic review and quality assessment

“…Full texts of these studies were retrieved and reviewed for inclusion. Finally, 24 potentially eligible studies were excluded 9,27‐49 , leaving 17 studies for inclusion (Appendix B). Table 1 provides an overview of the included studies.…”