One-year survival and resource use after critical illness: impact of organ failure and residual organ dysfunction in a cohort study in Brazil

Otavio T. Ranzani, Fernando G. Zampieri, Bruno A. M. P. Besen, Luciano C. P. Azevedo, Marcelo Park

To evaluate the impacts of organ failure and residual dysfunction on one-year survival and health care resource utilization, using the ICU discharge as the starting point. A historical cohort study, including all adult patients discharged alive after at least 72 h of ICU stay in a tertiary teaching hospital in Brazil. The starting point of follow-up was ICU discharge. Organ failure was defined as a value of three or four in its corresponding component of the SOFA score, and residual organ dysfunction was defined as a score of 1-2. We fit a multivariate flexible Cox model to predict one-year survival. We analyzed 690 patients. Mortality at one year after discharge was 27 %. Using multivariate modelling, age, chronic obstructive pulmonary disease, cancer, organ dysfunctions and albumin at ICU discharge were the main determinants of one-year survival. Age and organ failure were non-linearly associated with survival, and the impact of organ failure diminished over time. We conducted a subset analysis with 561 patients (81 %) discharged without organ failure over the previous 24 h of discharge, and the number of residual organs in dysfunction remained strongly associated with reduced one-year survival. The utilization of health care resources among hospital survivors was substantial within one year: 40 % of the patients were re-hospitalized, 52 % visited the emergency department, 90 % were seen at the outpatient clinic, 14 % attended rehabilitation outpatient services, 11 % were followed by the psychological/psychiatric service, and 7 % used the day hospital facility. Use of health care resources up to 30 days after hospital discharge was associated with the number of organs in dysfunction at ICU discharge. Organ failure was an important determinant of one-year outcomes of critically ill survivors. Nevertheless, the impact of organ failure tended to diminish over time. Resource utilization after critical illness was elevated among ICU survivors, and a targeted action is needed to deliver appropriate care and to reduce the late critical illness burden.