Document type
ArticleVersion
Published versionPublication date
Publication license
Please use this identifier to cite or link to this item: https://hdl.handle.net/2445/111161
The Influence of Body Mass Index on Outcomes in Patients Undergoing Cardiac Surgery: Does the Obesity Paradox Really Exist?
Journal Title
Director/Tutor
Journal ISSN
Volume Title
Related resource
Abstract
Purpose: Obesity influences risk stratification in cardiac surgery in everyday practice. However, some studies have reported better outcomes in patients with a high body mass index (BMI): this is known as the obesity paradox. The aim of this study was to quantify the effect of diverse degrees of high BMI on clinical outcomes after cardiac surgery, and to assess the existence of an obesity paradox in our patients. Methods: A total of 2,499 consecutive patients requiring all types of cardiac surgery with cardiopulmonary bypass between January 2004 and February 2009 were prospectively studied at our institution. Patients were divided into four groups based on BMI: normal weight (18.5
24.9 kg∙m−2; n = 523; 21.4%), overweight (25
29.9kg∙m−2; n = 1150; 47%), obese (≥30
≤34.9kg∙m−2; n = 624; 25.5%) and morbidly obese (≥35kg∙m−2; n = 152; 6.2%). Follow-up was performed in 2,379 patients during the first year. Results: After adjusting for confounding factors, patients with higher BMI presented worse oxygenation and better nutritional status, reflected by lower PaO2/FiO2 at 24h and higher albumin levels 48h after admission respectively. Obese patients showed a higher risk for Perioperative Myocardial Infarction (OR: 1.768; 95% CI: 1.035
3.022; p = 0.037) and septicaemia (OR: 1.489; 95% CI: 1.282
1.997; p = 0.005). In-hospital mortality was 4.8% (n = 118) and 1-year mortality was 10.1% (n = 252). No differences were found regarding in-hospital mortality between BMI groups. The overweight group showed better 1-year survival than normal weight patients (91.2% vs. 87.6%; Log Rank: p = 0.029. HR: 1.496; 95% CI: 1.062
2.108; p = 0.021). Conclusions: In our population, obesity increases Perioperative Myocardial Infarction and septicaemia after cardiac surgery, but does not influence in-hospital mortality. Although we found better 1-year survival in overweight patients, our results do not support any protective effect of obesity in patients undergoing cardiac surgery.
24.9 kg∙m−2; n = 523; 21.4%), overweight (25
29.9kg∙m−2; n = 1150; 47%), obese (≥30
≤34.9kg∙m−2; n = 624; 25.5%) and morbidly obese (≥35kg∙m−2; n = 152; 6.2%). Follow-up was performed in 2,379 patients during the first year. Results: After adjusting for confounding factors, patients with higher BMI presented worse oxygenation and better nutritional status, reflected by lower PaO2/FiO2 at 24h and higher albumin levels 48h after admission respectively. Obese patients showed a higher risk for Perioperative Myocardial Infarction (OR: 1.768; 95% CI: 1.035
3.022; p = 0.037) and septicaemia (OR: 1.489; 95% CI: 1.282
1.997; p = 0.005). In-hospital mortality was 4.8% (n = 118) and 1-year mortality was 10.1% (n = 252). No differences were found regarding in-hospital mortality between BMI groups. The overweight group showed better 1-year survival than normal weight patients (91.2% vs. 87.6%; Log Rank: p = 0.029. HR: 1.496; 95% CI: 1.062
2.108; p = 0.021). Conclusions: In our population, obesity increases Perioperative Myocardial Infarction and septicaemia after cardiac surgery, but does not influence in-hospital mortality. Although we found better 1-year survival in overweight patients, our results do not support any protective effect of obesity in patients undergoing cardiac surgery.
Subject (English)
Citation
Citation
LÓPEZ DELGADO, Juan Carlos, et al. The Influence of Body Mass Index on Outcomes in Patients Undergoing Cardiac Surgery: Does the Obesity Paradox Really Exist?. PLoS One. 2015. Vol. 10, num. 3, pags. e0118858. ISSN 1932-6203. [consulted: 10 of June of 2026]. Available at: https://hdl.handle.net/2445/111161