A cerebral aneurysm is a “weak spot” in an artery in the brain. This weakness allows the vessel to balloon outward and fill with blood, possibly leading to pressure on a nerve or brain tissue near the aneurysm. Aneurysms also can leak or rupture, causing blood to spill into the surrounding tissue (hemorrhage). What causes them and how do they relate to headaches?
Causes of Cerebra Aneurysms
Most aneurysms are present from birth (congenital), and may be present in as many as 3 to 6% of the population. They are more common in people with certain diseases or conditions, especially polycystic kidney disease and ateriovenous malformations. Other inherited risk factors for developing cerebral aneurysms include:
- Autosomal dominant polycystic kidney disease
- Type IV Ehlers-Danlos syndrome
- Pseudoxanthoma elasticum
- Hereditary hemorrhagic telangiectasia
- Neurofibromatosis type 1
- Alpha1-antitrypsin deficiency
- Coarctation of the aorta
- Fibromuscular dysplasia
- Klinefelter's syndrome
- Tuberous sclerosis
- Noonan's syndrome
- Alpha-glucosidase deficiency
- Age over 50 years
- Female gender
- Current cigarette smoking
- Alcohol use
- Cocaine use
- Infection of vessel wall
- Head trauma
- Intracranial neoplasm or neoplastic emboli
There is some evidence oral contraceptives (birth control pills) may be associated with the development of aneurysms, but the strength of that evidence is still unclear.
What Can Go Wrong With Cerebral Aneurysms?
The most significant problem with cerebral aneurysms is that they may rupture, causing bleeding into the surrounding brain tissue. This bleeding prevents blood (and oxygen) to flow to some areas of the brain, resulting in a stroke. Strokes can lead to potential permanent nerve damage or even death. If bleeding occurs into the space between the skull and brain (subarachnoid hemorrhage), there can eventually be a buildup of fluid surrounding the brain, putting additional pressure on the brain tissue.
How Are Cerebral Aneurysms and Headaches Related?
While cerebral aneurysms are often symptomless, they can cause headaches on occasion. While not common, even an aneurysm that has not ruptured may cause headaches in some individuals. A person may notice an abrupt, severe headache, or a series of headaches different from their “usual” ones. In the case of a ruptured aneurysm, patients will usually experience “the worse headache of their lives.” This headache may also be accompanied by nausea and vomiting, a brief loss of consciousness, one-sided weakness or vision loss, or severe neck pain.
What Should I Do?
In the case of a sudden, severe headache, you should call your health care provider right away. He or she can tell you what the best course of action at that time would be. You will likely need an emergency evaluation to determine if you have an aneurysm that has ruptured. Because aneurysms do not usually have symptoms until a catastrophe happens, it is difficult to know exactly what to do. Focusing on reducing the risks over which you have control (smoking, diet, etc.) would be the first step. Discussing any concerns you may have with your physician is another thing you can do to determine your risk and any appropriate testing. As with all headache symptoms, you and your health care provider should discuss headache warning signs so you can react appropriately.
“Cerebral Aneurysm Fact Sheet.” From the National Institute of Neurologic Disorders and Stroke website. Accessed 28 October 2009. http://www.ninds.nih.gov/disorders/cerebral_aneurysm/detail_cerebral_aneurysm.htm
Vega C, Kwoon JV, Lavine SD. “Intracranial aneurysms: current evidence and clinical practice.” Am Fam Physician. 2003 Apr 1;67(7):1438-9.