HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:
Guest Access | Sign In via User Name/Password

This Article Full Text Free Full Text (PDF) Free Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to My Personal Article Archive Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (47) Citing Articles via Google Scholar Google Scholar Articles by Tremblay, A. Articles by Bandi, V. Search for Related Content PubMed PubMed Citation Articles by Tremblay, A. Articles by Bandi, V.

Impact of Body Mass Index on Outcomes Following Critical Care^*

^* From the Department of Pulmonary and Critical Care Medicine, Baylor College of Medicine, Houston, TX.

Correspondence to: Alain Tremblay, MDCM, Division of Respiratory Medicine, Health Sciences Center, 3330 Hospital Dr NW, Calgary, AB, T2N 4N1 Canada; e-mail: atrembla{at}ucalgary.ca

Study objectives: To determine the impact of body mass index (BMI) on outcomes in critically ill patients.

Design: Retrospective analysis of a large multi-institutional ICU database.

Measurements: The influence of BMI classification (underweight, < 20 kg/m²; normal [control subjects], 20 to 25 kg/m²; overweight, 25 to 30 kg/m²; obese, 30 to 40 kg/m²; severe obesity, > 40 kg/m²) on hospital survival, functional status at hospital discharge, and ICU/hospital length of stay (LOS) was analyzed via multivariate analysis, adjusting for age, gender, type of hospital admission, and severity score (ie, simplified acute physiologic score [SAPS] II and mortality prediction model [MPM] at time zero). Univariate analysis also was performed according to the quartile of the severity score. All comparisons were to the normal BMI group.

Results: Of 63,646 patient datasets, 41,011 were complete for height, weight, and at least one of the two severity scores. We found increased mortality in underweight patients (odds ratio [OR] of death: SAPS group, 1.19; MPM group, 1.26) but not in overweight, obese, or severely obese patients. ICU and hospital LOS were increased in both the severely obese (OR of discharge: ICU, 0.81 and 0.84, respectively; hospital, 0.83 and 0.87, respectively) and underweight groups (OR of discharge: ICU, 0.96 and 0.94, respectively; hospital, 0.91 and 0.90, respectively). Only in the SAPS group did the obese group have increased ICU LOS (OR, 0.96) and hospital LOS (OR, 0.96). Functional status at discharge was impaired in underweight patients (OR of disability: ICU, 1.11; hospital, 1.19). Overweight patients had decreased discharge disability (OR of disability: SAPS, 0.93; MPM, 0.94), while the results in the obese group were discordant between the two severity score groups (SAPS, not significant; MPM, 0.91; p < 0.05 for all ORs).

Conclusions: Low BMI, but not high BMI, is associated with increased mortality and worsened hospital discharge functional status. LOS is increased in severely obese patients and, to a lesser extent, in underweight patients. Patients in the overweight and obese BMI groups may have improved mortality and discharge functional status.

Key Words: body mass index • ICU • length of stay • mortality • nutrition • obesity • severity of illness • underweight • weight

This article has been cited by other articles:

				K. M. Flegal, B. I. Graubard, D. F. Williamson, and M. H. Gail Cause-Specific Excess Deaths Associated With Underweight, Overweight, and Obesity JAMA, November 7, 2007; 298(17): 2028 - 2037. [Abstract] [Full Text] [PDF]

				G. J. Rodrigo and V. Plaza Body Mass Index and Response to Emergency Department Treatment In Adults With Severe Asthma Exacerbations: A Prospective Cohort Study Chest, November 1, 2007; 132(5): 1513 - 1519. [Abstract] [Full Text] [PDF]

				A. M. Cheung, C. M. Tansey, G. Tomlinson, N. Diaz-Granados, A. Matte, A. Barr, S. Mehta, C. D. Mazer, C. B. Guest, T. E. Stewart, et al. Two-Year Outcomes, Health Care Use, and Costs of Survivors of Acute Respiratory Distress Syndrome Am. J. Respir. Crit. Care Med., September 1, 2006; 174(5): 538 - 544. [Abstract] [Full Text] [PDF]

				A. S. Buchman, R. S. Wilson, J. L. Bienias, R. C. Shah, D. A. Evans, and D. A. Bennett Change in body mass index and risk of incident Alzheimer disease Neurology, September 27, 2005; 65(6): 892 - 897. [Abstract] [Full Text] [PDF]

				D. E. Ray, S. C. Matchett, K. Baker, T. Wasser, and M. J. Young The Effect of Body Mass Index on Patient Outcomes in a Medical ICU Chest, June 1, 2005; 127(6): 2125 - 2131. [Abstract] [Full Text] [PDF]

				M. J. Schultz, P. E. Spronk, C. Goulenok, and A. Cariou Overweight in ICU Patients: Is the Body Mass Index Reliable? Chest, February 1, 2005; 127(2): 683 - 684. [Full Text] [PDF]

				J.-P. Frat Obesity in ICU Patients: Increase or Decrease in Mortality? Chest, January 1, 2005; 127(1): 414 - 414. [Full Text] [PDF]

				J. M. O'Brien Jr., C. H. Welsh, R. H. Fish, M. Ancukiewicz, A. M. Kramer, and for the National Heart, Lung, and Blood Institute Excess Body Weight Is Not Independently Associated with Outcome in Mechanically Ventilated Patients with Acute Lung Injury Ann Intern Med, March 2, 2004; 140(5): 338 - 345. [Abstract] [Full Text] [PDF]