The impact of obesity on outcomes after critical illness: a meta-analysis

Intensive Care Med. 2009 Jul;35(7):1152-70. doi: 10.1007/s00134-009-1424-5. Epub 2009 Feb 3.


Purpose: To assess whether obesity is associated with mortality or other adverse intensive care unit (ICU) and post-ICU outcomes.

Methods: A meta-analysis of studies from PubMed and EMBASE databases.

Results: Twenty-two studies (n = 88,051 patients) were included. Pooled analysis demonstrated no difference in ICU mortality, but lower hospital mortality for obese and morbidly obese subjects (RR 0.76; 95% CI 0.59, 0.92; RR 0.83; 95% CI 0.66, 1.04, respectively) versus normal weight subjects. There was no association between obesity and duration of mechanical ventilation or ICU stay. Morbidly obese versus normal weight patients had longer hospitalizations. No study reported physical function, mental health, or quality of life outcomes after discharge.

Conclusions: Obesity is not associated with increased risk for ICU mortality, but may be associated with lower hospital mortality. There is a critical lack of research on how obesity may affect complications of critical illness and patient long-term outcomes.

Publication types

  • Meta-Analysis
  • Review

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Critical Illness / mortality*
  • Humans
  • Intensive Care Units
  • Middle Aged
  • Obesity / complications*
  • Treatment Outcome*
  • Young Adult