Aneurysms – to treat or not to treat?
Not all brain aneurysms that are discovered by chance will rupture (tear). But various factors increase the risk of a rupture, causing bleeding in the brain.
When a brain aneurysm is diagnosed, doctors try to determine the risk of complications. In other words, they try to find out how likely it is that the aneurysm will eventually burst and cause life-threatening bleeding in the brain.
This risk is higher if the aneurysm has particular characteristics or if you have certain other medical conditions. Habits like smoking can increase the risk too.
What increases the likelihood of rupture?
The larger the aneurysm, the greater the risk of complications. There is no specific size at which “harmless” aneurysms become “dangerous.” But experts believe that aneurysms that are smaller than seven millimeters in diameter don't need to be treated at first, and can simply be monitored.
There's still a chance that small aneurysms will rupture, though. Because of this, other risk factors should be considered too when deciding whether or not to have treatment. For example, the risk of rupture is considered to be higher if an aneurysm
- grows over time
- is located in the brain arteries that supply the back part of the brain
- has an irregular shape
The risk is also higher in patients who have more than one brain aneurysm – particularly if one of them has already bled.
Aside from the characteristics of the aneurysm itself, complications are more common in
- people with high blood pressure,
- people who smoke or drink a lot of alcohol,
- older people and
- people with a family history of the disease – in other words, people who have a close relative such as a brother, sister or parent who has already had a ruptured aneurysm.
What can I do to lower my risk?
You can avoid or at least influence the following important risk factors:
- High blood pressure
- Too much alcohol
You can do quite a bit to lower high blood pressure. Changes in diet, weight loss, and getting more exercise can help. There are also effective medications for high blood pressure.
Smokers diagnosed with an aneurysm can reduce the risk of rupture by quitting smoking. Many smokers find this difficult to do. But various things can help you quit smoking.
The same applies to alcohol. Depending on how much you drink, you may need professional help to quit. If you want to drink less alcohol but not stop completely, try to drink only occasionally or at special events.
Does the risk suggest that treatment is needed?
After a brain aneurysm is diagnosed, the main focus is on deciding whether the aneurysm needs to be treated. To make a decision, it's important to know how likely it is that the aneurysm will eventually rupture.
If the risk of bleeding in the brain is very low, treatment might cause more harm than good because it is associated with risks and side effects itself. On the other hand, treatment could prevent life-threatening bleeding in the brain in people who are at very high risk. For them, the benefits outweigh the possible side effects.
Whether an aneurysm will eventually rupture depends on many different factors. Also, the risk of bleeding in the brain must be weighed against the possible side effects and risks associated with the treatment. The treatment-related risks vary from person to person too. For all of these reasons, it's sometimes difficult to decide whether or not to have treatment. It's important to talk to doctors who specialize in the treatment of brain aneurysms.
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