gms | German Medical Science

Objective: Subarachnoid hemorrhage (SAH) is usually caused by a ruptured intracranial aneurysm, but in some patients no source of hemorrhage can be detected. More recent data showed increasing numbers of spontaneous non-aneurysmal SAH (non-aSAH). Our objective was to analyze factors, especially patients using systemic anticoagulation and/or antiplatelet medication (aCP+), influencing the increasing numbers and the clinical outcome.

Method: Between 1999 and 2013 214 patients suffered from non-aSAH, 14% of all patients with SAH. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months. Risk factors were identified based on the outcome.

Results: We identified increasing numbers of patients with non-aSAH. Over the periods the rate of perimesencephalic (PM) SAH decreased, whereas the rate of non-PM (NPM) SAH increased. The rate of aCP+ increased statistically significant. Favorable outcome (mRS 0 - 2) was achieved in 85%, but aCP+ patients had a significant higher risk for an unfavorable outcome. The further analysis showed that especially the subgroup of 'Fisher 3 bleeding pattern' had a high risk for an unfavorable outcome, whereas the subgroup NPM-SAH without Fisher 3 bleeding pattern had a similar favorable outcome like PM-SAH.

Conclusions: Due to changes of patients' admission in the last years we identified significant higher rates of aCP+ and therefore higher amounts of bleedings and worse outcome. Especially elderly patients with Fisher type 3 blood patterns and aCP+ were at risk for unfavorable outcome. Therefore, for further investigations NPM-SAH should be stratified into patients with or without Fisher 3 blood pattern.