title: Predictors of Delayed Cerebral Ischemia in Patients with Aneurysmal Subarachnoid Hemorrhage with Asymptomatic Angiographic Vasospasm on Admission.
abstract: BACKGROUND
  Risk of delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH) with asymptomatic angiographic vasospasm on admission is unclear in the literature. The goal of this study is to identify predictors of clinical DCI in this group of patients.
  
  
  METHODS
  An exploratory subgroup analysis was conducted in the SAHIT (Subarachnoid Hemorrhage International Trialists) data repository to identify predictors of clinical DCI in patients with good-grade aSAH (World Federation of Neurological Surgeons grade I and II) with angiographic vasospasm on admission. Predictors considered include age, sex, systolic blood pressure at presentation, World Federation of Neurological Surgeon grade, Fisher grade, aneurysm size and location, treatment modality, hydrocephalus requiring external ventricular drain insertion, and severity of vasospasm. The predictors were ranked based on dominance analysis with R2as fit statistics and assessed in a set of logistic regression analysis models.
  
  
  RESULTS
  Four data sets out of 16 studies in the SAHIT database were analyzed, with a total of 4125 patients. One hundred and ninety-one patients (4.6%) had asymptomatic angiographic vasospasm at admission. Of those, 78 patients (40.8%) developed clinical DCI. Univariate analysis showed significant associations between severe vasospasm on admission and development of clinical DCI (odds ratio, 9.5, 95% confidence interval, 2.07-43.50; P = 0.004). None of the studied predictors was associated with the development of clinical DCI on multivariate analysis.
  
  
  CONCLUSIONS
  Asymptomatic angiographic vasospasm in patients with good-grade aSAH on admission is uncommon. Further studies are needed to identify high-risk patients for the development of DCI in the context of asymptomatic early vasospasm.
authors.affiliation: Division of Neurosurgery, Department of Surgery, University of Toronto, Ontario, Canada; Division of Neurosurgery, Department of Surgery, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Abdulrahman
authors.initials: A
authors.lastname: Aldakkan
authors.affiliation: Division of Neurosurgery, Department of Surgery, University of Toronto, Ontario, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Alireza
authors.initials: A
authors.lastname: Mansouri
authors.affiliation: Division of Neurosurgery, St. Michael's Hospital, Labatt Family Centre of Excellence in Brain Injury and Trauma Research, Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Surgery, University of Toronto, Ontario, Canada.
authors.forename: Blessing N R
authors.initials: BN
authors.lastname: Jaja
authors.affiliation: Division of Neurosurgery, Department of Surgery, University of Toronto, Ontario, Canada.
authors.forename: Naif M
authors.initials: NM
authors.lastname: Alotaibi
authors.affiliation: Division of Neurosurgery, Department of Surgery, University of Toronto, Ontario, Canada; Division of Neurosurgery, St. Michael's Hospital, Labatt Family Centre of Excellence in Brain Injury and Trauma Research, Keenan Research Centre for Biomedical Science and the Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Surgery, University of Toronto, Ontario, Canada. Electronic address: macdonaldlo@smh.ca.
authors.forename: R Loch
authors.initials: RL
authors.lastname: Macdonald
mesh_terms: D002545:Brain Ischemia / Q000000981:diagnostic imaging* / Q000453:epidemiology; D002533:Cerebral Angiography / Q000639:trends; D017321:Clinical Trials, Phase I as Topic / Q000379:methods; D017322:Clinical Trials, Phase II as Topic / Q000379:methods; D006801:Humans; D010343:Patient Admission / Q000639:trends; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000000981:diagnostic imaging* / Q000453:epidemiology; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging* / Q000453:epidemiology
keywords: Aneurysmal subarachnoid hemorrhage; Delayed cerebral ischemia; Vasospasm