Long term outcome after subarachnoid haemorrhage of unknown aetiology.

Background And Purpose: The aim of this study was to assess the long term outcome after non-aneurysmal subarachnoid haemorrhage (SAH).

Methods: 1154 patients with SAH were treated in our hospital between 1989 and 1999. From this patient population, 97 patients had a non-aneurysmal SAH. All hospital records and death certificates were studied and 33 patients were examined by MRI and MR angiography more than 9 years (mean 12 years) after the initial bleeding.

Results: The cohort consisted of 97 patients. Mean follow-up time was 9 years (range 0-19). During the follow-up period, 13 patients (13%) died. Four (4%) died from the initial bleeding less than 5 weeks after the initial haemorrhage. There was no delayed mortality due to SAH or subsequent bleedings. MR angiography revealed no new findings in 33 surviving patients.

Conclusions: Excess mortality during the first year after SAH was higher than 4%, and remained thereafter comparable with the general population. There were no rebleedings and MR imaging did not reveal any vascular pathology that could explain the earlier SAH.