We examined whether complication rates and resource utilization among elderly patients undergoing coronary artery bypass grafting (CABG) differed from their younger counterparts. A retrospective review of prospectively collected data was conducted of 2936 patients undergoing first-time isolated CABG. Demographic and baseline clinical characteristics were collected, and patients grouped according to age into those <75 years (n=2424, younger) and >or=75 years (n=512, older). Major postoperative complications were recorded and data collected on indicators of resource utilization, which included intensive care unit (ICU) length of stay (LOS), postoperative LOS and total hospital LOS. In comparison with younger patients, older patients were more likely to be female (26.6% vs. 18.1%, P<0.0001) and require an urgent procedure (46.4% vs. 33.3%, P<0.0001). Postoperative complications were significantly higher in elderly patients (43.7% vs. 23.0%; odds ratio (OR)=2.5, 95% confidence interval (CI) [2.0-3.1]; P<0.0001). Older patients incurred longer intensive care stays (2 days interquartile range (IQR) [1-3] vs. 1 day IQR [1-2]; P<0.0001) and a longer postoperative stay (8 days IQR [6-11] vs. 6 days IQR [5-8]; P<0.0001). Multivariate logistic regression analysis showed age >or=75 years was an independent predictor of postoperative LOS (OR=1.23, 95% CI [0.49-1.96]; P=0.001). Older patients aged >or=75 years undergoing CABG had significantly higher rates of postoperative complications and greater resource utilization than their younger counterparts.