Lederle FA et al. (2008) Abdominal aortic aneurysm events in the women's health initiative: cohort study. BMJ 337: a1724

Little is known about the etiology of and risk factors for abdominal aortic aneurysm (AAA) in women. Lederle et al. have now published data from a large, multicenter, prospective, observational study that has revealed that hormone replacement therapy and diabetes exert protective effects against AAA in their all-female cohort.

The Women's Health Initiative enrolled a total of 161,808 postmenopausal women aged 50–79 years (mean 65.2 years), 301 of whom reported having a previous aortic aneurysm. During follow-up of the whole cohort (mean 7.8 years) 184 AAA events occurred, which resulted in 14 deaths. Multivariate analysis identified several strong predictors of risk for AAA in this population, including having ever smoked (OR 1.94), being a current smoker (OR 4.19 or 8.73 compared with never having smoked), hypertension (OR 2.14), coronary artery disease (OR 2.38), peripheral artery disease (OR 1.81), and the patient's age (OR 1.77). The consumption of alcohol did not increase the risk of AAA. Current and past use of postmenopausal hormone therapy was associated with a reduced risk of AAA (ORs 0.48 and 0.76, respectively). Furthermore, women with diabetes were around 70% less likely to experience AAA than were those without diabetes. This finding supports the negative association between diabetes and AAA previously seen among men. The authors advocate further studies to elucidate the biological mechanisms responsible for these risk reductions.