title: Prognosis of acute subdural haematoma from intracranial aneurysm rupture.
abstract: BACKGROUND
  Acute subdural haematoma (aSDH) is a rare complication of aneurysmal subarachnoid haemorrhage (SAH) and is associated with poor clinical condition on admission and poor outcome.
  
  
  OBJECTIVE
  The aim of this study was to assess whether aneurysmal aSDH is an independent risk factor for poor outcome.
  
  
  METHODS
  In a series of 1632 patients retrieved from our prospectively collected single centre SAH database and fulfilling prespecified inclusion criteria, we found 53 patients with aSDH on the initial CT scan. From the same series, we collected 660 patients in whom aSDH was ruled out by reviewing the initial CT scan. We compared the risk of poor outcome at discharge and at 3 months between patients with and without aSDH by calculating crude risk ratios (RRs) with corresponding 95% CIs, and adjusting for age, sex, location and treatment modality of the aneurysm that bled, clinical condition on admission, intracerebral haemorrhage, intraventricular haemorrhage and hydrocephalus, with Poisson regression.
  
  
  RESULTS
  Patients with aSDH had a higher risk of poor outcome at discharge (crude RR 1.59; 95% CI 1.35 to 1.86) and at 3 months (crude RR: 2.17, 95% CI 1.79 to 2.62) than patients without aSDH. After simultaneous adjustment for five characteristics that affected the crude RR, the RR for poor outcome for patients with aSDH at discharge was 1.15 (95% CI 0.97 to 1.37) and at 3 months 1.30 (95% CI 1.04 to 1.62).
  
  
  CONCLUSIONS
  The presence of aSDH in patients with aneurysmal SAH is an independent risk factor for poor outcome at 3 months.
authors.affiliation: Utrecht Stroke Centre, Department of Neurology and Neurosurgery, Rudolf Magnus Institute of Neuroscience, University Medical Centre, Utrecht, The Netherlands. J.M.Biesbroek@umcutrecht.nl
authors.forename: J Matthijs
authors.initials: JM
authors.lastname: Biesbroek
authors.forename: Jan Willem Berkelbach
authors.initials: JW
authors.lastname: van der Sprenkel
authors.forename: Ale
authors.initials: A
authors.lastname: Algra
authors.forename: Gabriel J E
authors.initials: GJ
authors.lastname: Rinkel
mesh_terms: D017542:Aneurysm, Ruptured / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D002543:Cerebral Hemorrhage / Q000150:complications / Q000175:diagnosis; D005260:Female; D020199:Hematoma, Subdural, Acute / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D006849:Hydrocephalus / Q000150:complications / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012307:Risk Factors; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000175:diagnosis; D014057:Tomography, X-Ray Computed