Abstract 13175: Outcomes of Heart Failure (HF) Patients Admitted to the Intensive Care Unit (ICU): Impact of Early or Late ICU Admission

Abstract

Background: Little is known about the outcomes of HF patients who are admitted to an ICU. We examined the outcomes of HF patients who were admitted to directly to the ICU (early) or admitted to the ICU after initial ward admission (late), compared to non-ICU admitted patients. Methods: We examined 118,595 HF patients (ICD-10 code I50) in Ontario, Canada, who were hospitalized from 2003-2012 using the Canadian Institute for Health Information Discharge Abstract Database. We examined the association of ICU admission and timing with: a) 30-day mortality using multiple Cox regression with time-varying covariates, and b) 30-day hospital readmissions using repeated events analysis approach of Prentice, Williams and Peterson. Results: Of the cohort, 24,119 (20%) were admitted to an ICU during the hospital stay, of whom 84% were admitted early (median age 76 years, 54% men) and 16% were admitted later (age 77 years, 53% men). 30-day mortality was higher in early and late ICU compared to no ICU: 13%, 27%, 10.5% (p <.001). Multivariable-adjusted hazard ratios (HR) were: 1.65 (95%CI; 1.58-1.73) for early ICU (p<.001) and 4.59 (95%CI; 4.31-4.89) for late ICU (p<.001) vs. no ICU (referent). All-cause 30-day readmissions were also highest among late ICU, followed by early ICU, and lowest in non-ICU patients: 24.3, 22.9, 21.7 readmissions per 100 person-months (all p <.001). Multivariable-adjusted repeated events analysis demonstrated a progressively increasing HRs for all-cause readmission: 1.07 (95%CI; 1.04-1.11) for early ICU (p<.001) and 1.13 (95%CI; 1.04-1.22) for late ICU (p<.01) vs. no ICU (referent). Median in-hospital costs were $16,553 for late ICU, $8587 for early ICU, and $7296 for non-ICU admitted patients (p <.001). Conclusions: HF patients who are admitted to the ICU are sicker and experience increased risk of 30-day readmissions and death. Late ICU admissions were associated with the highest risk of death and readmission, and incurred substantially higher costs of care.