title: How does prior health status (age, comorbidities and frailty) determine critical illness and outcome?
abstract: Critical illness has a significant impact on an individual's physical and mental health. However, it is less clear to what degree outcomes after critical illness are due to patients' preexisting characteristics, rather than the critical illness itself. In this review, we summarize recent findings regarding the role of age, comorbidity and frailty on long-term outcomes after critical illness.
  
  
  
  Age, comorbidity and frailty are all associated with an increased risk of critical illness. Although severity of illness drives the risk of acute mortality, recent data suggest that longer term outcomes are much more closely aligned with prior health status. There are growing data regarding the important role of noncardiovascular comorbidity, including psychiatric illness and obesity, in determining long-term outcomes. Finally, preadmission frailty is associated with poor long-term outcomes after critical illness; further data are needed to evaluate the attributable impact of critical illness on the health trajectories of frail individuals.
  
  
  
  Age, comorbidity and frailty play a critical role in determining the long-term outcomes of patients requiring intensive care.
authors.affiliation: aDepartment of Surgery and Interdepartmental Division of Critical Care, University of Toronto bDepartment of Critical Care Medicine, Sunnybrook Health Sciences Centre cDepartment of Anesthesia and Interdepartmental Division of Critical Care, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Barbara
authors.initials: B
authors.lastname: Haas
authors.forename: Hannah
authors.initials: H
authors.lastname: Wunsch
mesh_terms: D000367:Age Factors; D015897:Comorbidity; D003422:Critical Care; D016638:Critical Illness / Q000453:epidemiology / Q000628:therapy*; D000073496:Frailty; D006304:Health Status; D006801:Humans; D008603:Mental Health; D017063:Outcome Assessment, Health Care