Early and Late Mortality Following Discharge From the ICU: A Multicenter Prospective Cohort Study*

Abstract

OBJECTIVES: To identify the frequency, causes, and risk factors of early and late mortality among general adult patients discharged from ICUs. DESIGN: Multicenter, prospective cohort study. SETTING: ICUs of 10 tertiary hospitals in Brazil. PATIENTS: One-thousand five-hundred fifty-four adult ICU survivors with an ICU stay greater than 72 hours for medical and emergency surgical admissions or greater than 120 hours for elective surgical admissions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The main outcomes were early (30 d) and late (31 to 365 d) mortality. Causes of death were extracted from death certificates and medical records. Twelve-month cumulative mortality was 28.2% (439 deaths). The frequency of early mortality was 7.9% (123 deaths), and the frequency of late mortality was 22.3% (316 deaths). Infections were the leading cause of death in both early (47.2%) and late (36.4%) periods. Multivariable analysis identified age greater than or equal to 65 years (hazard ratio, 1.65; p = 0.01), pre-ICU high comorbidity (hazard ratio, 1.59; p = 0.02), pre-ICU physical dependence (hazard ratio, 2.29; p < 0.001), risk of death at ICU admission (hazard ratio per 1% increase, 1.008; p = 0.03), ICU-acquired infections (hazard ratio, 2.25; p < 0.001), and ICU readmission (hazard ratio, 3.76; p < 0.001) as risk factors for early mortality. Age greater than or equal to 65 years (hazard ratio, 1.30; p = 0.03), pre-ICU high comorbidity (hazard ratio, 2.28; p < 0.001), pre-ICU physical dependence (hazard ratio, 2.00; p < 0.001), risk of death at ICU admission (hazard ratio per 1% increase, 1.010; p < 0.001), and ICU readmission (hazard ratios, 4.10, 4.17, and 1.82 for death between 31 and 60 days, 61 and 90 days, and greater than 90 days after ICU discharge, respectively; p < 0.001 for all comparisons) were associated with late mortality. CONCLUSIONS: Infections are the main cause of death after ICU discharge. Older age, pre-ICU comorbidities, pre-ICU physical dependence, severity of illness at ICU admission, and ICU readmission are associated with increased risk of early and late mortality, while ICU-acquired infections are associated with increased risk of early mortality.