The cause of AAA is unclear. Some researchers believe that it may be associated with atherosclerosis, the buildup of cholesterol and fat (plaque) on the artery walls, or risk factors that contribute to atherosclerosis, such as high blood pressure and smoking.
High-risk populations include:
- Men older than age 60,
- People with high blood pressure,
- People with chronic obstructive pulmonary disease, and
- People with vascular diseases.
Aneurysms may also be genetic, or rarely, can be caused by trauma, connective tissue disease, or bacterial or fungal infections.