Outcomes in octogenarians undergoing coronary artery bypass grafting

Abstract

Background: Although octogenarians are being referred for coronary artery bypass grafting (CABG) with increasing frequency, contemporary outcomes have not been well described. We examined data from 4 Canadian centres to determine outcomes of CABG in this age group.

Methods: Data for the years 1996 to 2001 were examined in a comparison of octogenarians with patients less than 80 years of age. Logistic regression analysis was used to adjust for preoperative factors and to generate adjusted rates of mortality and postoperative stroke.

Results: A total of 15,070 consecutive patients underwent isolated CABG during the study period. Overall, 725 (4.8%) were 80 years of age or older, the proportion increasing from 3.8% in 1996 to 6.2% in 2001 (p for linear trend = 0.03). The crude rate of death was higher among the octogenarians (9.2% v. 3.8%; p < 0.001), as was the rate of stroke (4.7% v. 1.6%, p < 0.001). The octogenarians had a significantly greater burden of comorbid conditions and more urgent presentation at surgery. After adjustment, the octogenarians remained at greater risk for in-hospital death (odds ratio [OR] 2.64, 95% confidence interval [CI] 1.95-3.57) and stroke (OR 3.25, 95% CI 2.15-4.93). Mortality declined over time for both age groups (p for linear trend < 0.001 for both groups), but the incidence of postoperative stroke did not change (p for linear trend = 0.61 [age < 80 years] and 0.08 [age > or = 80 years]). Octogenarians who underwent elective surgery had crude and adjusted rates of death (OR 1.31, 95% CI 0.60-2.90) and stroke (OR 1.59, 95% CI 0.57-4.44) that were higher than but not significantly different from those for non-octogenarians who underwent elective surgery.

Interpretation: In this study, rates of death and stroke were higher among octogenarians, although the adjusted differences in mortality over time were decreasing. The rate of adverse outcomes in association with elective surgery was similar for older and younger patients.

Fig. 1: Adjusted mortality over time (with 95% confidence intervals). For patients less than 80 years old, p for linear trend < 0.001; for those 80 years of age and older, p for linear trend < 0.001. The rates were adjusted for the following variables: centre, sex, urgency, presence of diabetes, preoperative renal failure, ejection fraction, hypertension, cerebrovascular disease, peripheral vascular disease, chronic obstructive pulmonary disease, heart failure, previous myocardial infarcation, redo surgery, left main disease; age and year of surgery were excluded.

Fig. 2: Adjusted stroke rates over time (with 95% confidence intervals). For patients less than 80 years old, p for linear trend = 0.61; for those 80 years of age and older, p for linear trend = 0.08. The rates were adjusted for the following variables: centre, sex, urgency, presence of diabetes, preoperative renal failure, ejection fraction, hypertension, cerebrovascular disease, peripheral vascular disease, chronic obstructive pulmonary disease, heart failure, previous myocardial infarction, redo surgery and left main disease; age and year of surgery were excluded.