Study Seeks to Evaluate Intervention Threshold for AAAs in Women
March 9, 2018—In Journal of Vascular Surgery (JVS), Stephanie M. Tomee, et al published findings from a study that analyzed sex-related differences in the epidemiology of ruptured abdominal aortic aneurysms (AAAs) to establish an intervention threshold for an endovascular versus surgical strategy in treating women (2018;67:735–739).
The analysis included all patients with emergency or elective AAA repair between January 1, 2013, and December 31, 2015, who were registered in the Dutch Surgical Aneurysm Audit, a compulsory, nationwide registry of AAA repairs in The Netherlands. The main outcomes were age, sex, AAA diameter at time of rupture, and 30-day postoperative mortality.
As summarized in JVS, 1,561 ruptured AAA repairs (14.7% women) and 7,063 cases of elective AAA repairs (13.7% women) were included in the analysis. Women had significantly smaller mean AAA diameter at the time of rupture than men (70.5 ± 14.4 mm vs 78.6 ± 17.5 mm). In male patients, 8% of ruptures occurred at diameters below the 55-mm intervention threshold. The female equivalent of this eighth percentile is 52 mm.
The investigators reported that female patients had significantly higher 30-day mortality after emergency repair than male patients (33% vs 24.2%), but they were also significantly older (76.7 ± 7.1 years vs 73.9 ± 8.3 years). Correcting for age reduced the 30-day mortality risk for women after ruptured AAA repair from 1.53 (95% confidence interval [CI], 1.14–2.04) to 1.27 (95% CI, 0.92–1.73). Outcomes after open elective repair was significantly worse for women compared with men, with a 30-day mortality of 7.97% versus 4.27% (P < .01).
The equivalent of the 55-mm intervention threshold for elective endovascular AAA repair in men is 52 mm in women. The mortality risk for elective open repair in women was almost doubled, which implies that the optimal point for open repair is at higher diameters, very possibly at least 55 mm, concluded the investigators in JVS.