Lack of relationship between obesity and mortality or morbidity after coronary artery bypass grafting

Area of Science:

• Cardiovascular Surgery
• Obesity Research
• Surgical Outcomes

Background:

• Obesity presents significant cardiovascular risks.
• Existing data on body mass index (BMI) and coronary artery bypass grafting (CABG) outcomes are conflicting.
• Understanding BMI's impact on CABG patients is crucial for surgical decision-making.

Purpose of the Study:

• To compare the outcomes of coronary artery bypass grafting (CABG) patients across different body mass index (BMI) categories.
• To investigate whether obesity is associated with increased mortality or morbidity after CABG.

Main Methods:

• Retrospective analysis of isolated CABG patients from July 2010 to June 2012.
• Patients were categorized into four BMI groups: normal (≤25 kg/m²), overweight (>25-30 kg/m²), obese (>30-35 kg/m²), and morbidly obese (>35 kg/m²).
• Outcomes including 30-day mortality, composite morbidity, and long-term survival were compared across groups.

Main Results:

• Increasing BMI correlated with younger age and higher creatinine clearance.
• Obesity was linked to higher rates of Maori/Pacific ethnicity and hypertension.
• Morbid obesity was associated with female sex, higher deprivation index, diabetes, longer operation times, and sternal wound infection.
• Crucially, 30-day mortality, composite morbidity, and survival rates were similar across all BMI categories.

Conclusions:

• Over a third of CABG patients were overweight or obese, with 13% being morbidly obese.
• Contrary to some expectations, obesity was not found to be a risk factor for adverse outcomes after CABG.
• These results indicate that obesity should not be considered a contraindication for CABG surgery.