Gender and 30-day outcome in patients undergoing endovascular aneurysm repair (EVAR): An analysis using the ACS NSQIP dataset

Abstract

Prior studies have demonstrated higher in-hospital mortality in women undergoing open abdominal aortic aneurysm repair. The current study evaluates the relationship between gender and 30-day outcomes for endovascular aneurysm repair (EVAR) in a multicenter, contemporary patient population. Patients in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) participant use file that underwent EVAR of abdominal aortic aneurysm (AAA) from 2005 to 2007 were identified by CPT codes. Outcomes analyzed were 30-day mortality, morbidity (one or more of 21 complications defined by the ACS NSQIP protocol), length of hospital stay, and six complication subgroups. Preoperative risk factors, intraoperative variables, and outcomes were compared across genders using chi(2) (binary and categorical variables) and t tests (continuous variables). The relationship of gender to outcomes was further evaluated using multivariate logistic regressions to adjust for pre- and intraoperative risk variables. In 3662 EVAR patients, 647 (17.7%) were women and 3015 (82.3%) men with mean ages of 75.1 +/- 9.0 and 73.7 +/- 8.5 years (P < .001). Tube graft (360, 9.8%); bifurcated, one docking limb (1624, 44.3%); bifurcated, two docking limbs (1294, 35.3%); unibody (218, 5.9%); and aorto-uni-iliac/femoral (166, 4.4%) repairs were performed. Tube and aorto-uni-iliac/femoral grafts were more common in women (21.4% vs 12.8%, P < .001) than men, as were femoral/femoral crossovers (3.9% vs 1.8%, P = .011) and iliac or brachial exposures (2.8% vs 1.0%, P = .009). Overall morbidity and mortality were 11.9% and 2.1%, respectively. Mortality in women was significantly higher (3.4% vs 2.1%, P = .014), as was morbidity (17.8% vs 10.6%, P < .001). Of thirteen independent preoperative risk factors for mortality or morbidity, women had a higher incidence in five: emergent operation, functional dependence, recent weight loss, underweight status or morbid obesity, and severe chronic obstructive pulmonary disease (COPD). After adjustment for these variables, the odds ratio (OR) for mortality in women vs men was 1.52 (95% confidence interval [CI] 0.85-2.69, P = .157); OR for morbidity was 1.65 (95% CI 1.28-2.14, P < .001). Female gender was also found to be an independent risk factor for length of stay (Beta 0.7 days, 95% CI 0.2-1.2, P = .006), infectious complications (OR 1.49, 95% CI 1.10-2.03, P = .011), wound complications (OR 1.80, 95% CI 1.12-2.90, P = .015) and postoperative transfusion (OR 2.92, 95% CI 1.39-6.13, P = .002). Mortality and morbidity were higher in women than men undergoing EVAR. Multivariate analysis showed that the increased risk of mortality was related to women presenting more emergently, more debilitated (recent weight loss and functional dependence), and requiring iliac or brachial exposure. After adjustment for multiple preoperative and operative factors, women remained at significantly higher risk for the development of a broad range of complications and increased length of stay.