Many people who experience severe headaches are often concerned about having a brain aneurysm. What prompted this post is a patient I just saw who was found to have a small (3 mm) aneurysm on a routine MRI scan as well as a new article just published in The Lancet Neurology.
Considering that over 36 million Americans suffer from migraine headaches, this is by far the most common cause of severe headaches. However, aneurysms are not rare – more than 7 million Americans have them. The vast majority of these people do not know that they have an aneurysm and in 50 to 80 percent they never cause headaches or any other problems. Every year, more than 30,000 people do suffer a rupture of the aneurysm. The rupture of an aneurysm is what causes a very severe headache and about one in seven people with a rupture die before reaching the hospital. In addition to a severe headache, the hemorrhage from a ruptured aneurysm can cause a stiff neck, drowsiness, weakness or numbness on one side, difficulty speaking and other symptoms of a stroke.
Dutch researchers analyzed the available data, trying to find predictors of aneurysm rupture. They discovered that the risk goes up with age, high blood pressure (hypertension), history of a previous brain hemorrhage, aneurysm size, its location and the geographic region. There is nothing one can do about age and other factors, but blood pressure is one factor that can be controlled.
If the aneurysm is less than 5 mm, as in my recent patient, the risk of a rupture is very low. However, if the aneurysm is larger, surgical treatment is usually indicated, especially if other risk factors are present.
It is not clear why, but people living in Finland and Japan are about 3 times more likely to have an aneurysm rupture than those in the rest of Europe and North America.
