TORONTO — Obesity was linked to an increased risk for postsurgical complications in a study of more than 11,000 patients who underwent coronary bypass surgery.
But in this series, obesity did not result in a significantly increased risk for postsurgical mortality, Dr. Mahboob Alam said at the 14th World Congress on Heart Disease.
Obesity also was linked to a significant 38% reduced risk for repeat operations for postoperative bleeding, an unexpected finding that requires further study to understand, said Dr. Alam, a cardiologist at Baylor College of Medicine, Houston.
The retrospective study included 11,417 consecutive patients who underwent coronary artery bypass surgery at St. Luke's Episcopal Hospital in Houston during 1996–2006. The series included 2,257 patients (20%) who were obese, which is defined as having a body mass index of 30 kg/m
The nonobese patients were older, with an average age of 64 years, compared with an average age of 61 in the obese patients. But the obese patients had more comorbidities, with higher rates of unstable angina, coronary artery disease, hypertension, heart failure, and diabetes.
The primary end point for the analysis was mortality during the first 30 days following bypass surgery, and although the obese patients had an 8% increased risk for death in a multivariate analysis, this difference was not statistically significant relative to the nonobese patients, Dr. Alam said at the congress sponsored by the International Academy of Cardiology.
The multivariate analysis showed that obesity was linked with significant increases in the rate of several new-onset morbidities, compared with nonobese patients following coronary artery bypass, including a 43% increased rate of renal insufficiency, a 71% increased rate of myocardial infarction, a 46% rise in respiratory failure, a 2.9-fold increased rate of sternal wound infections, and a 2.1-fold boost in the rate of leg wound infections.
Obesity was tied to a higher risk of renal insufficiency, MI, and respiratory failure. DR. ALAM