Coronary artery bypass graft surgery outcomes among African-Americans and Caucasian patients

There have been few studies to date that investigate the effect of race on outcomes related to coronary artery bypass grafting. The objective of the present study was to investigate race as an independent predictor of outcomes among patients undergoing coronary artery bypass graft (CABG). A nested case-control study from a twelve-year hospitalization cohort (N=9671) in which data were collected prospectively was conducted. Cases were African-American patients undergoing CABG (N=644). Controls were randomly selected Caucasian patients undergoing CABG (N=1932). Controls were matched to cases 3:1 on year of surgery. Fifteen preoperative and intraoperative risk factors and 14 outcomes were examined. The 14 outcomes of interest were length of stay, readmission to ICU, total ICU stay, total hours on ventilator post-op, reoperation for bleeding/tamponade, deep sternal wound infection, neurological complications, pneumonia, other pulmonary complications, renal failure, gastrointestinal complications, atrial fibrillation requiring treatment, in-hospital mortality, and intraoperative complications. Regression analysis was used to control for risk factors. Multivariate analysis revealed African-Americans were at greater risk for renal complications (OR 1.88, 95% CI 1.27-2.77), neurological complications (OR 1.34, 95% CI 1.01-1.77), and pulmonary complications (OR 2.11, 95% CI 1.72-2.59). African Americans had a significantly longer hospitalization post-operatively (OR 0.79, 95% CI 0.66-0.96), but were less likely to experience post-operative atrial fibrillation requiring treatment than Caucasians (OR 0.64, 95% CI 0.49-0.84). Even after multiple adjustments, African-Americans undergoing CABG surgery had significantly greater morbidity compared to Caucasian patients.