title: Analysis of nonmodifiable risk factors for intracranial aneurysm rupture in a large, retrospective cohort.
abstract: BACKGROUND
  The risk factors predictive of intracranial aneurysm rupture remain incompletely defined.
  
  
  OBJECTIVE
  To examine the association between various nonmodifiable risk factors and aneurysm rupture in a large cohort of patients evaluated at a single institution.
  
  
  METHODS
  A retrospective analysis of patients admitted to a cerebrovascular facility between January 2006 and 2010 with a primary diagnosis of cerebral aneurysm. Aneurysms were divided into 2 groups: unruptured or ruptured. The dome diameter, aspect ratio (AR), location, sidedness, neck morphology, and multiplicity were entered into a central database. A full model was constructed, and a systematic removal of the least significant variables was performed in a sequential fashion until only those variables reaching significance remained.
  
  
  RESULTS
  We identified 2347 patients harboring 5134 individual aneurysms, of which 34.90% were ruptured and 65.09% were unruptured. On admission, 25.89% of aneurysms with a dome diameter <10 mm and 58.33% of aneurysms with a dome >10 mm were ruptured (P < .001). Of aneurysms with an AR >1.6, 52.44% presented following a rupture (P < .001). The highest incidence of rupture (69.21%) was observed in aneurysms with an AR >1.6, dome diameter <10 mm, and a deviated neck. Deviated neck-type aneurysms had a significantly greater incidence of rupture than classical neck-type aneurysms (P < .001).
  
  
  CONCLUSIONS
  An AR >1.6, dome diameter >10 mm, a deviated neck, and right-sidedness are independently associated with aneurysm rupture.
authors: Department of Neurological Surgery, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
authors: Peter S
authors: PS
authors: Amenta
authors: Sanjay
authors: S
authors: Yadla
authors: Peter G
authors: PG
authors: Campbell
authors: Mitchell G
authors: MG
authors: Maltenfort
authors: Saugat
authors: S
authors: Dey
authors: Sayantani
authors: S
authors: Ghosh
authors: Muhammad S
authors: MS
authors: Ali
authors: Jack I
authors: JI
authors: Jallo
authors: Stavropoula I
authors: SI
authors: Tjoumakaris
authors: L Fernando
authors: LF
authors: Gonzalez
authors: Aaron S
authors: AS
authors: Dumont
authors: Robert H
authors: RH
authors: Rosenwasser
authors: Pascal M
authors: PM
authors: Jabbour
mesh_terms: D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D015331:Cohort Studies; D016208:Databases, Factual / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors