Intracranial aneurysms: family history and risk of rupture

Intracranial aneurysms are acquired dilations of the arteries in the brain. Approximately 3% of the adult population has an intracranial aneurysm. When an intracranial aneurysm bursts (this is also called rupture) this results in aneurysmal subarachnoid haemorrhage (aSAH), a subtype of stroke. The most important group of persons at increased risk for aSAH are those who have family members who have had an aSAH (also called those with a positive family history for aSAH). In persons with a positive family history, aSAH can be prevented by imaging the brain’s arteries looking for intracranial aneurysms. Intracranial aneurysms detected in this way can then be treated before aSAH occurs.

In this thesis, we present a family history questionnaire to identify whether a relative experienced an aSAH or another stroke type. We also describe two models to predict the presence of an intracranial aneurysm at first and during follow-up screening in persons with a positive family history of aSAH. Additionally, we show a higher rupture risk of intracranial aneurysms in women and in persons with a positive family history of aSAH compared to men and persons without a positive family history of aSAH.

In conclusion, this thesis presents ways to optimise the identification and screening of persons with a positive family history of aSAH. A more aggressive preventive treatment approach of unruptured intracranial aneurysms in women and in persons with a positive family history of aSAH may be justified.