title: Clinical, laboratory, and radiographic predictors of the occurrence of seizures following aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  At present, the administration of prophylactic antiepileptic medication following aneurysmal subarachnoid hemorrhage (SAH) is controversial, and the practice is heterogeneous. Here, the authors sought to inform clinical decision making by identifying factors associated with the occurrence of seizures following aneurysm rupture.
  
  
  METHODS
  Exploratory analysis was performed on 413 patients enrolled in CONSCIOUS-1 (Clazosentan to Overcome Neurological Ischemia and Infarction Occurring after Subarachnoid Hemorrhage), a prospective randomized trial of clazosentan for the prevention of angiographic vasospasm. The association among clinical, laboratory, and radiographic covariates and the occurrence of seizures following SAH were determined. Covariates with a significance level of p < 0.20 on univariate analysis were entered into a multivariate logistic regression model. Receiver operating characteristic (ROC) curve analysis was used to define optimal predictive thresholds.
  
  
  RESULTS
  Of the 413 patients enrolled in the study, 57 (13.8%) had at least 1 seizure following SAH. On univariate analysis, a World Federation of Neurosurgical Societies grade of IV-V, a greater subarachnoid clot burden, and the presence of midline shift and subdural hematomas were associated with seizure activity. On multivariate analysis, only a subarachnoid clot burden (OR 2.76, 95% CI 1.39-5.49) and subdural hematoma (OR 5.67, 95% CI 1.56-20.57) were associated with seizures following SAH. Using ROC curve analysis, the optimal predictive cutoff for subarachnoid clot burden was determined to be 21 (of a possible 30) on the Hijdra scale (area under the curve 0.63).
  
  
  CONCLUSIONS
  A greater subarachnoid clot burden and subdural hematoma are associated with the occurrence of seizures after aneurysm rupture. These findings may help to identify patients at greatest risk for seizures and guide informed decisions regarding the prescription of prophylactic anticonvulsive therapy. Clinical trial registration no.: NCT00111085 (ClinicalTrials.gov).
authors.affiliation: Division of Neurosurgery, St. Michael's Hospital, Labatt Family Centre of Excellence in Brain Injury and Trauma Research, Keenan Research Centre of the Li Ka Shing Knowledge Institute of St. Michael's Hospital, and Department of Surgery, University of Toronto, Ontario, Canada.
authors.forename: George M
authors.initials: GM
authors.lastname: Ibrahim
authors.forename: Aria
authors.initials: A
authors.lastname: Fallah
authors.forename: R Loch
authors.initials: RL
authors.lastname: Macdonald
mesh_terms: D000328:Adult; D000368:Aged; D000927:Anticonvulsants / Q000627:therapeutic use*; D003657:Decision Making; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011859:Radiography; D012306:Risk; D012640:Seizures / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D013345:Subarachnoid Hemorrhage / Q000150:complications* / Q000000981:diagnostic imaging
chemical_list: D000927:Anticonvulsants