Risk of epilepsy in long-term survivors of surgery for aneurysmal subarachnoid hemorrhage: a population-based study in Iceland

Epilepsia. 2000 Sep;41(9):1201-5. doi: 10.1111/j.1528-1157.2000.tb00326.x.


Purpose: Epilepsy is known to result from aneurysmal subarachnoid hemorrhage (SAH). There are no population-based estimates of the absolute risk or the duration for which this risk is elevated. We have conducted a population-based study in Iceland of the risk of epilepsy after a ruptured cerebral aneurysm to address these questions.

Methods: The index patients are all of the patients who presented with SAH caused by ruptured cerebral aneurysm in Iceland during an 11-year period (1958 to 1968) and survived more than 6 months. We determined the number of index patients who developed epilepsy. The observed number of cases of epilepsy was compared with that expected based on the incidence of epilepsy in Iceland.

Results: There were 44 index patients; 11 (25%) developed epilepsy, all within 4 years of the insult. Seven (70%) of 10 patients with acute symptomatic seizures (defined as seizures during the first 2 weeks after the hemorrhage) developed epilepsy (relative risk, 7.0; 95% confidence interval, 2.3-21.6). Epilepsy was more frequent in patients with severe neurological residua (48%) compared with patients without (20%) (relative risk, 2.5; 95% confidence interval, 0.9-6.3).

Conclusions: The risk for epilepsy among survivors of SAH caused by ruptured cerebral aneurysm is substantially increased. Both acute symptomatic seizure and persistent neurological impairment are associated with a further increase in the risk of epilepsy.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Epilepsy / epidemiology*
  • Epilepsy / etiology
  • Humans
  • Iceland / epidemiology
  • Intracranial Aneurysm / surgery
  • Postoperative Complications / epidemiology*
  • Postoperative Complications / etiology
  • Rupture
  • Subarachnoid Hemorrhage / surgery*