Abdominal Aortic Aneurysm - Causes

Causes

The exact causes of the degenerative process remain unclear. There are, however, some hypotheses and well-defined risk factors.

• Tobacco smoking: Greater than 90% of people who develop an AAA have smoked at some point in their life.
• Genetic influences: The influence of genetic factors is highly probable. The high familial prevalence rate is most notable in male individuals. There are many hypotheses about the exact genetic disorder that could cause higher incidence of AAA among male members of the affected families. Some presumed that the influence of alpha 1-antitrypsin deficiency could be crucial, while other experimental works favored the hypothesis of X-linked mutation, which would explain the lower incidence in heterozygous females. Other hypotheses of genetic etiology have also been formulated. Connective tissue disorders, such as Marfan syndrome and Ehlers-Danlos syndrome, have also been strongly associated with AAA. Both relapsing polychondritis and pseudoxanthoma elasticum may cause abdominal aortic aneurysm.
• Atherosclerosis: The AAA was long considered to be caused by atherosclerosis, because the walls of the AAA are frequently affected heavily. However, this hypothesis cannot be used to explain the initial defect and the development of occlusion, which is observed in the process.
• Other causes: Other causes of the development of AAA include: infection, trauma, arteritis, cystic medial necrosis (m. Erdheim).