Prospective Study of Long-term Outcome After Non-aneurysmal Subarachnoid Hemorrhage

Spontaneous subarachnoid hemorrhage (SAH) is usually caused by rupture of an intracranial aneurysm, but in up to 15% of patients with spontaneous SAH, no discernible bleeding source can be identified despite of repetitive radiological imaging. The blood distribution can be described as perimesencephalic/prepontine or non-perimesencephalic. Depending on the pattern of SAH the clinical course of the patients can be similar to aneurysmal SAH. In general, patients with a perimesencephalic SAH (PM-SAH) are considered to achieve good outcome and to have lower rebleeding risk. However, long-term outcome data on patients suffering from spontaneous non-aneurysmal SAH (non-aSAH) is scarce and lacking for physical and psychological outcome. Therefore, the aim of the present study was to investigate the long-term physical and psychological outcome in patients suffering from non-aneurysmal spontaneous SAH.

SAH was confirmed on computed tomography (CT) or lumbar puncture. Only patients with a non-traumatic SAH were included. In our hospital algorithm all patients with SAH underwent angiography including 3D digital subtraction angiography (DSA) since 2002 to rule out intracranial sources for SAH. In case of a negative initial angiography, DSA was repeated after 14 days. Additionally, magnetic resonance imaging (MRI) of head/spine was performed to rule out any spinal bleeding sources. In patients with blood distribution exceeding the typical perimesencephalic pattern, a third DSA was performed 3 months after SAH. The first (short-term) follow-up (F/U) was performed six months after ictus. Outcome was measured according to the modified Rankin Scale (mRS) and stratified into favorable (mRS 0-2) and unfavorable (mRS 3-6) after six months. Patients with non-aSAH were divided into perimesencephalic SAH (PM-SAH), non-perimesencephalic SAH (NPM-SAH) and excellent Outcome group (mRS 0). Also the NPM-SAH group was further stratified into Fisher 3 blood pattern and NPM-SAH without Fisher 3 blood pattern.

Patients, at least 18 months after ictus of a non-aneurysmal SAH, received a regular mail including a letter explaining the study purpose and the postal questionnaire consisting a short-form health survey with 36 simple questions. If we didn't receive answers after three months we made telephone interviews with the patients' family members or their general practitioner.