Women have worse long-term outcomes after coronary artery bypass grafting than men.

Background: Multiple studies have shown that women have worse in-hospital outcomes than men after coronary artery bypass grafting (CABG). The impact of sex on long-term results following CABG, however, is not as well established.

Objective: To compare long-term results in men and women undergoing CABG.

Methods: A total of 3404 patients underwent isolated CABG between 1995 and 1999 with follow-up until 2000. Univariate comparisons between men and women were carried out based on pre- and intraoperative variables and short- and long-term adverse outcomes. Long-term adverse outcomes were defined as all-cause mortality or rehospitalization for any cardiac cause, and were risk-adjusted using multivariate modelling techniques.

Results: Compared with men, women undergoing CABG were, on average, older (67.8 years versus 64.2 years), more likely to have diabetes (P<0.0001) and hypertension (P<0.0001), and more likely to present for surgery with urgent/emergent status (P<0.0001). Intra-operatively, women had fewer bypasses (3.0 versus 3.3; P<0.0001) and were less likely to receive a left internal mammary artery graft (P=0.0001). While rates of in-hospital mortality were comparable between women and men (2.9% versus 2.2%; P=0.22), women were more likely to experience a long-term adverse event (30.2% versus 23.5%; P<0.0001). After adjusting for clinical differences between men and women, sex emerged as an independent predictor of long-term adverse outcomes following CABG (hazard ratio = 1.18, P=0.03).

Conclusions: Women presented for CABG with more comorbid illness, advanced symptoms and greater urgency than did men. After adjusting for differences in clinical presentation, sex emerged as an independent predictor of long-term adverse outcomes following CABG.