What causes brain aneurysms?

What causes brain aneurysms?

It’s not clear why a brain aneurysm forms. Researchers believe these factors irritate and weaken blood vessels:

• Smoking.
• Blood infection.
• High blood pressure (hypertension).
• Amphetamine and cocaine use.
• Traumatic brain injury (often caused by car crashes).
• Atherosclerosis (fatty buildup on blood-vessel walls).