What causes a brain aneurysm?
A person may inherit the tendency to form aneurysms, or aneurysms may develop because of hardening of the arteries (atherosclerosis) and aging. Some risk factors that can lead to brain aneurysms can be controlled, and others can’t. The following risk factors may increase your risk for an aneurysm or, if you already have an aneurysm, may increase your risk of it rupturing:
- Family history. People who have a family history of brain aneurysms are more likely to have an aneurysm than those who don’t.
- Previous aneurysm. People who have had a brain aneurysm are more likely to have another.
- Gender. Women are more likely to develop a brain aneurysm or to suffer a subarachnoid hemorrhage.
- Race. African Americans are more likely than whites to have a subarachnoid hemorrhage.
- High blood pressure. The risk of subarachnoid hemorrhage is greater in people who have a history of high blood pressure.
- Smoking. In addition to being a cause of high blood pressure, the use of cigarettes may greatly increase the chances of a brain aneurysm rupturing.
What causes an abdominal aortic aneurysm
Most aortic aneurysms occur in the part of your aorta that’s in your abdomen. Although the exact cause of abdominal aortic aneurysms is unknown, a number of factors may play a role, including:
- Tobacco use. Cigarette smoking and other forms of tobacco use appear to increase your risk of aortic aneurysms. In addition to the damaging effects that smoking causes directly to the arteries, smoking contributes to the buildup of fatty plaques in your arteries (atherosclerosis) and high blood pressure. Smoking can also cause your aneurysm to grow faster by further damaging your aorta.
- Hardening of the arteries (atherosclerosis). Atherosclerosis occurs when fat and other substances build up on the lining of a blood vessel, increasing your risk of an aneurysm.
- Infection in the aorta (vasculitis). In rare cases, abdominal aortic aneurysm may be caused by an infection or inflammation that weakens a section of the aortic wall.