Impact of obesity on outcomes in a multiethnic cohort of medical intensive care unit patients

Purpose: To examine the association of obesity with in-hospital mortality and complications during critical illness. Methods: We performed a retrospective analysis of a multiethnic cohort of 699 patients admitted to medical intensive care unit between January 2010 and May 2011 at Mount Sinai St. Luke’s and Mount Sinai West Hospitals, tertiary care centers in New York City. Multivariate logistic regression analysis was used to evaluate the association between obesity (body mass index [BMI] ≥ 30] and in-hospital mortality. Subgroup analysis was performed in elderly patients (age ≥65 years). Results: Compared to normal BMI, obese patients had lower in-hospital mortality (24.4% vs 17.6%, P ¼.04). On multivariate analysis, obesity was independently associated with lower in-hospital mortality (odds ratio [OR]: 0.49, 95% confidence interval [CI]: 0.27-0.89, P ¼.018). There was no significant difference in rates of mechanical ventilation, reintubation, and vasopressor requirement across BMI categories. In subgroup analysis, elderly obese patients did not display lower in-hospital mortality (adjusted OR: 0.85, 95% CI: 0.40-1.82, P ¼. 68). Conclusion: Our study supports the hypothesis that obesity is associated with decreased mortality during critical illness. However, this finding was not observed among elderly obese patients. Further studies should explore the interaction between age, obesity, and outcomes in critical illness.