Effect of gender on postoperative outcomes and hospital stays after coronary artery bypass grafting

Background. Compared to men, women undergoing coronary artery bypass grafti ng appear to have a higher morbidity and mortality, particularly in the per ioperative period. This study was designed to answer the questions of wheth er such differences in clinical outcomes between men and women still exist with improvements in surgical techniques and determine whether it is gender or associated comorbid conditions in women that lead to higher morbidity. Methods. An analysis of a single center's contemporary experience (1994 to 1997) of 1,743 consecutive patients undergoing primary coronary artery bypa ss grafting was performed. Only reoperations were excluded. Data were colle cted prospectively and presented as mean +/- standard deviation (p < 0.05). Results. Women represented 30.0% of patients. Compared with men, women were older (68.4 versus 63.8 years; p < 0.05), and had more urgent surgical int erventions (70.0% versus 56.7%; p < 0.05), a higher incidence of diabetes ( 42.1% versus 26.7%; p < 0.05), hypertension (82.0% versus 73.9%; p < 0.05), lower body surface area (1.73 +/- 0.18 m(2) versus 2.03 +/- 0.19 m(2); p < 0.05), and hematocrit (31.7% +/- 3.9% versus 36.2% +/- 3.9%; p < 0.05). Ej ection fraction, incidence of previous myocardial infarction, chronic obstr uctive pulmonary disease, left main (LM) disease, renal insufficiency, exte nt of coronary disease, and preoperative intraaortic balloon pump were simi lar. Women received fewer arterial grafts (91.0% versus 95.5%; p < 0.05) an d distal anastomoses (3.31 +/- 0.88 versus 3.49 +/- 0.94 p < 0.05). Despite these differences, there were no statistical differences in the incidence of postoperative death (1.5% versus 1.0%), myocardial infarction (0.6% vers us 0.6%), or cerebrovascular accident/transient ischemic attack (1.1% versu s 0.4%) between men and women. Women had a higher inotropic support (10.2% versus 4.4%; p < 0.05) and longer hospital stays (7.3 +/- 5.7 days versus 6 .3 +/- 4.2 days; p < 0.05). Using multivariate analysis, female gender was not an independent predictor of death or postoperative complications but wa s a predictor of length of hospital stay, use of arterial grafts, and exten t of coronary revascularization. Conclusions. After accounting: for differences in their risk variables, the incidences of death, perioperative myocardial infarction and cerebrovascul ar accident/ transient ischemic attack after coronary artery bypass graftin g in women and men were not statistically significant. Perioperative compli cations are related to comorbid risk factors but not to female gender itsel f. Further studies are warranted.