Effect of obesity on intensive care morbidity and mortality: a meta-analysis. Crit Care Med

Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Western New York Respiratory Research Center, University at Buffalo School of Medicine and Biomedical Sciences, Buffalo, NY, USA.
Critical care medicine (Impact Factor: 6.31). 01/2008; 36(1):151-8. DOI: 10.1097/01.CCM.0000297885.60037.6E
Source: PubMed

ABSTRACT To evaluate the effect of obesity on intensive care unit mortality, duration of mechanical ventilation, and intensive care unit length of stay among critically ill medical and surgical patients.
Meta-analysis of studies comparing outcomes in obese (body mass index of > or = 30 kg/m2) and nonobese (body mass index of < 30 kg/m2) critically ill patients in intensive care settings.
MEDLINE, BIOSIS Previews, PubMed, Cochrane library, citation review of relevant primary and review articles, and contact with expert informants.
Not applicable.
A total of 62,045 critically ill subjects.
Descriptive and outcome data regarding intensive care unit mortality and morbidity were extracted by two independent reviewers, according to predetermined criteria. Data were analyzed using a random-effects model.
Fourteen studies met inclusion criteria, with 15,347 obese patients representing 25% of the pooled study population. Data analysis revealed that obesity was not associated with an increased risk of intensive care unit mortality (relative risk, 1.00; 95% confidence interval, 0.86-1.16; p = .97). However, duration of mechanical ventilation and intensive care unit length of stay were significantly longer in the obese group by 1.48 days (95% confidence interval, 0.07-2.89; p = .04) and 1.08 days (95% confidence interval, 0.27-1.88; p = .009), respectively, compared with the nonobese group. In a subgroup analysis, an improved survival was observed in obese patients with body mass index ranging between 30 and 39.9 kg/m2 compared with nonobese patients (relative risk, 0.86; 95% confidence interval, 0.81-0.91; p < .001).
Obesity in critically ill patients is not associated with excess mortality but is significantly related to prolonged duration of mechanical ventilation and intensive care unit length of stay. Future studies should target this population for intervention studies to reduce their greater resource utilization.

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Available from: Ali El Solh, Jul 26, 2014
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    Injury 11/2014; 45(11):1798–1799. DOI:10.1016/j.injury.2013.09.033 · 2.14 Impact Factor
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    • "However, published data on outcome in overweight children and adults is conflicting [11–14]. Broadly, adult intensive care unit (AICU) data suggest increased duration of mechanical ventilation and ICU stay but no clear association with mortality [15–17]. "
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    Intensive Care Medicine 07/2014; 40(8). DOI:10.1007/s00134-014-3381-x · 7.21 Impact Factor
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    • "Findings to date are not conclusive, with some studies reporting no association between obesity and mortality [14,15], and others finding that low body mass index (BMI) is associated with increased mortality [15-17], or that excess weight is a negative prognostic factor [18,19]. Two meta-analyses pooling data on studies evaluating the impact of obesity on outcomes in ICU patients did not find an association between obesity and mortality in critical illness [20,21]. "
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    ABSTRACT: Background Obesity and diabetes mellitus are well-defined risk factors for cardiovascular mortality. The impact of antecedent hyperglycemia and body size on mortality in critical ill patients in intensive care units (ICUs) may vary across their range of values. Therefore, we prospectively analyzed the relationship between in-hospital mortality and preexisting hyperglycemia and body size in critically ill ICU patients to understand how mortality varied among normal, overweight, and obese patients and those with low, intermediate, and high glycated hemoglobin (HbA1c) levels. Methods Medical history, weight, height, physiologic variables, and HbA1c were obtained during the first 24 h for patients who were consecutively admitted to the high complexity ICU of Hospital de Clínicas de Porto Alegre, Brazil, from April to August 2011. The relationships between mortality and obesity and antecedent hyperglycemia were prospectively analyzed by cubic spline analysis and a Cox proportional hazards model. Results The study comprised 199 patients. The overall hospital mortality rate was 43.2% during a median 16 (8–28) days of follow-up. There was a progressive risk of in-hospital mortality with higher HbA1c levels, with the relationship becoming significant at HbA1c >9.3% compared with lower levels (hazard ratio 1.74; 95% confidence interval with Bonferroni correction 1.49–2.80). In contrast, mean body mass index (BMI) was higher in survivors than in nonsurvivors (27.2 kg/m2 ± 7.3 vs. 24.7 kg/m2 ± 5.0 P = 0.031, respectively). Cubic spline analysis showed that these relationships differed nonlinearly through the spectrum of BMI values. In a Cox proportional hazards model adjusted for Acute Physiology and Chronic Health Evaluation II score and HbA1c, the risk of in-hospital mortality progressively decreased with increasing BMI (BMI <20 vs. 20–23.9 kg/m2, P = 0.032; BMI <20 vs. 24–34.9 kg/m2, P = 0.010; BMI <20 vs. ≥35 kg/m2, P = 0.032). Conclusions Our findings suggest that significant hyperglycemia prior to ICU admission is a risk factor for in-hospital mortality. Conversely, increasing BMI may confer an advantageous effect against mortality in critical illness independently of previous glycemic control.
    BMC Endocrine Disorders 06/2014; 14(1):50. DOI:10.1186/1472-6823-14-50 · 1.71 Impact Factor
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