- A subarachnoid haemorrhage (SAH) occurs when a bulge in a weakened artery, called an aneurysm, bursts in the brain.
- The chances of surviving are only about 50%, and victims who live often face a lifetime of disability.
- Researchers in Korea investigated 426 cases of SAH between 2002 and 2004.
- Patients were compared with a group of 426 people matched for age and sex who had not experienced a brain bleed.
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