Abdominal Aortic Aneurysm – More Common In Men, More Dangerous In Women
Abdominal aortic aneurysms in women are known to be more aggressive than in men. In women abdominal aortic aneurysms expand more rapidly and are more prone to rupture. Abdominal aortic aneurysms in women are also associated with a higher death when they rupture.
Men are much more likely to have an abdominal aortic aneurysm than women. Up to 5% of men may have an abdominal aortic aneurysm compared to up to 1% of women. The standard definition of an abdominal aortic aneurysm is a diameter of ≥ 30mm, a definition that may lead to underestimating the true number of significant aneurysms in woman.
Abdominal aortic aneurysms are more aggressive in women. They grow faster, there are more likely to rupture and they are more likely to result in death when they rupture. The rupture typically occurs at smaller aorta sizes when compared to men. Unfortunately, fewer women undergo repair once they present with rupture, which likely further contributes to the poor outcomes seen in women.
Risk Factors For Abdominal Aortic Aneurysm In Woman
Risk factors for the development of abdominal aortic aneurysm include many of the classic risk factors for cardiovascular disease such as age, smoking, blood pressure etc.
Abdominal aortic aneurysm is a result of degeneration of the wall of the aorta. The wall of the aorta is made up of many different cell types that are surrounded by a matrix that acts as a scaffold. There is a complex interplay going on at all times between cells that build up the wall and scaffold and cells that break this down. In aneurysm formation, experimental studies suggest that there is inflammation and activation of cells break down the aortic wall and weaken it. It is also felt that estrogen in women plays a protective role against aneurysm formation while in men, male hormones can be somewhat destructive.
Should Woman Be Routinely Tested For Abdominal Aortic Aneurysm?
In men, ultrasound scans of the abdomen have been demonstrated as an effective method of screening for abdominal aortic aneurysm. Current guidelines from the leading societies recommend a one time screening ultrasounds to all men 65 or older who have ever smoked or who have a family history of abdominal aortic aneurysm. Amazingly there are no current widespread recommendations for screening women with ultrasound. This is mainly due to a lack of evidence as most the research has been done on men and the data regarding women is mixed in its findings. Some recommendations are against screening women as they say it would not be effective whereas others recommend screening woman age 65 or older that have smoked or have had a family history of abdominal aortic aneurysm.
Should Abdominal Aortic Aneurysm Be Fixed Earlier In Women?
Since aneurysms are more likely to rupture in women even at a smaller size, there is a debate over whether abdominal aortic aneurysms should be fixed earlier in women. In trials looking at fixing abdominal aortic aneurysms earlier in the population in general, women were underrepresented and so it’s difficult to draw conclusions. It’s important to note that when women undergo surgery in general for abdominal aortic aneurysm that they have worse outcomes as compared to men. For this reason many people feel that it is not appropriate to operate earlier than the standard recommendations in women.
How Are Abdominal Aortic Aneurysms Fixed In Women?
As things stand the minimally invasive, non surgical, EVAR has become the mainstay of treatment for abdominal aortic aneurysm, however some studies report that in women the outcomes are significantly worse as compared to men. Other studies however report similar results of EVAR in men and women.
There have been may suggested reasons for women doing worse in general after procedures for abdominal aortic aneurysm. Women typically develop abdominal aortic aneurysm at a later age and are also less likely to receive attention to risk factors such as smoking, blood pressure and cholesterol. When undergoing repair with EVAR, women are more likely to have access site complications such as damage to the leg vessels through which the procedure is performed. This is likely because women have smaller leg vessels in general.