Influence of obesity on in-hospital and early mortality and morbidity after myocardial revascularization.

OBJECTIVE: Obese patients are thought to have an increased risk for complications in coronary artery bypass surgery. Several risk stratification systems do not identify obesity as a variable for risk adjustment. The aim of this study is to evaluate the in-hospital and early (one year) mortality and morbidity in obese and non-obese patients after a CABG in the UMC St Radboud. METHODS: The data of 1130 patients undergoing a myocardial revascularization from January 2000 to August 2002 were analyzed. Obesity was measured by the body mass index (BMI). A BMI>or=30 kg/m2 was defined as obese. We compared 206 obese patients with 924 non-obese patients. Uni- and multivariate analysis were used to analyze the results. The 1-year survival was analyzed using Kaplan-Meier methods. RESULTS: There were no significant differences between obese and non-obese patients according to postoperative myocardial infarction, re-operation for bleeding, in-hospital mortality, renal complications, neurological complications, pulmonary complications, gastrointestinal complications, re-intubation, re-admission on intensive care, ventilation time, days on intensive care, days in hospital and late mortality. Only the incidence of postoperative wound infections was increased in obese patients, 8.3% in the obese versus 4.4% in the non-obese (P=0.02). Multivariate analysis identified obesity only as risk factor for postoperative for wound infections (P=0.04, odds ratio: 1.97). CONCLUSIONS: Obese patients do not have an increased risk of in-hospital and early (1 year) mortality after CABG. However, obese patients have an increased risk of postoperative wound infections compared to non-obese patients.