Risk factors
By Mayo Clinic staffA number of factors can contribute to weakness in an artery wall and increase the risk of a brain aneurysm. Brain aneurysms are more common in adults than in children and more common in women than in men. Some of these risk factors develop over time; others are present at birth.
Risk factors that develop over time
These include:
- Older age
- Smoking
- High blood pressure (hypertension)
- Hardening of the arteries (arteriosclerosis)
- Drug abuse, particularly the use of cocaine
- Head injury
- Heavy alcohol consumption
- Certain blood infections
- Lower estrogen levels after menopause
Risk factors present at birth
These include:
- Inherited connective tissue disorders, such as Ehlers-Danlos syndrome, that weaken blood vessels
- Polycystic kidney disease, an inherited disorder that results in fluid-filled sacs in the kidneys and usually increases blood pressure
- Abnormally narrow aorta (coarctation of the aorta), the large blood vessel that delivers oxygen-rich blood from the heart to the body
- Cerebral arteriovenous malformation (brain AVM), an abnormal connection between arteries and veins in the brain that interrupts the normal flow of blood between them
- Family history of brain aneurysm, particularly a first-degree relative, such as a parent, brother or sister
- Cerebral aneurysm fact sheet. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/cerebral_aneurysm/detail_cerebral_aneurysm.htm. Accessed Feb. 28, 2011.
- Singer RJ, et al. Treatment of aneurysmal subarachnoid hemorrhage. http://www.uptodate.com/home/index.html. Accessed Feb. 18, 2011.
- Cerebral aneurysm. American Association of Neurological Surgeons. http://www.aans.org/Patient%20Information/Conditions%20and%20Treatments/Cerebral%20Aneurysm.aspx. Accessed Feb. 28, 2011.
- Singer RJ, et al. Unruptured intracranial aneurysms. http://www.uptodate.com/home/index.html. Accessed Feb. 18, 2011.
- Westerlaan HE, et al. Intracranial aneurysms in patients with subarachnoid hemorrhage: CT angiography as a primary examination tool for diagnosis - a systematic review and meta-analysis. Radiology. 2011;258:134.
- Naggara ON, et al. Endovascular treatment of intracranial unruptured aneurysms: Systematic review and meta-analysis of the literature on safety and efficacy. Radiology. 2010;256:887.
- Hacein-Bey L, et al. Current imaging assessment and treatment of intracranial aneurysms. American Journal of Roentgenology. 2011;196:32.


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