In the present series , overweight and obese patients had similar or slightly lower in-hospital mortality rates after cardiac surgery compared with normal-weight individuals .
Conversely , postoperative complication rates increased with higher BMI levels .
Most studies included in the review showed that overweight and obese patients had at least the same mortality rate as normal-weight patients , or even a lower death risk .
Pooled- data of the meta- analysis provided evidence on the association between higher BMI levels and a lower all-cause in-hospital mortality rate after cardiac surgery
The relationship between higher body mass index ( BMI ) , decreased morbidity and mortality is known as the " obesity paradox " , and has been described in cohorts of patients with hypertension , diabetes , heart failure , coronary and peripheral artery diseases , non-cardiac surgery , and end-stage renal disease .
Here we investigated the relationship between BMI and short-term outcomes after adult cardiac surgery to explore the existence of an obesity paradoxical effect .
A secondary objective was to perform an up date d systematic review to further analyze the association between BMI and 30-day in-hospital mortality after cardiac surgery .
Relationship of body mass index with outcomes after coronary artery bypass graft surgery.
BACKGROUND A debate exists whether obesity is a risk factor for operative mortality after  coronary artery bypass graft surgery ( CABG ) . The contradictory findings in the literature may largely be attributable to the variety of method ological approaches used to model the association between body mass index ( BMI ) and post-CABG outcomes . This study aims to investigate this association , and to uncover possible explanations for the lack of consensus across prior studies . METHODS Data were prospect ively collected on 80,792 patients who underwent a CABG procedure during a 14-year period at the 45 Department of Veterans Affairs cardiac surgery programs .  Generalized additive models were used to estimate the relationship of BMI and outcomes after a CABG procedure . RESULTS We found that the relationship of BMI with post-CABG mortality and morbidity is U-shaped with the minimum risk located around a BMI of 30 kg/m2 , indicating that patients classified as overweight have the lowest risk , and those in the lower end of the obese range do not have seriously elevated risk . This U-shape relationship is significantly nonlinear and robust to adjustment for other risk factors . CONCLUSIONS This study demonstrates that BMI is an independent predictor of mortality and morbidity after CABG surgery . Previous studies that model BMI linearly or as categories can not accurately capture this U-shaped relationship and are unlikely to find a significant contribution by including BMI . Further research is needed to determine the mechanisms of risk for patients with low and high BMI and whether interventions to modify BMI may improve patient outcomes
In the present series , overweight and obese patients had similar or slightly lower in-hospital mortality rates after cardiac surgery compared with normal-weight individuals .
Conversely , postoperative complication rates increased with higher BMI levels .
Most studies included in the review showed that overweight and obese patients had at least the same mortality rate as normal-weight patients , or even a lower death risk .
Pooled- data of the meta- analysis provided evidence on the association between higher BMI levels and a lower all-cause in-hospital mortality rate after cardiac surgery
The relationship between higher body mass index ( BMI ) , decreased morbidity and mortality is known as the " obesity paradox " , and has been described in cohorts of patients with hypertension , diabetes , heart failure , coronary and peripheral artery diseases , non-cardiac surgery , and end-stage renal disease .
Here we investigated the relationship between BMI and short-term outcomes after adult cardiac surgery to explore the existence of an obesity paradoxical effect .
A secondary objective was to perform an up date d systematic review to further analyze the association between BMI and 30-day in-hospital mortality after cardiac surgery .