title: Characteristics of brain arteriovenous malformations with coexisting aneurysms: a comparison of two referral centers.
abstract: BACKGROUND
  Patients harboring a brain arteriovenous malformation (BAVM) often have coexisting arterial aneurysms. Experts have argued about the clinical significance of these aneurysms, which may be important for risk stratification in patient management and clinical trials. We studied the association between coexisting aneurysms and initial presentation with intracranial hemorrhage (ICH) in patients with BAVM evaluated at two tertiary-care centers.
  
  
  METHODS
  Demographic and clinical data were collected from a prospective series of patients evaluated for BAVM at the University of California, San Francisco (UCSF; n=82), and Columbia-Presbyterian Medical Center, New York (CPMC; n=254). Using multivariate logistic regression, we examined the independent association between ICH presentation and the presence of a coexisting aneurysm, and compared the association at the two hospitals.
  
  
  RESULTS
  Aneurysms were associated with 28 BAVMs at UCSF (34%) and 74 at CPMC (29%; P=0.39). Initial presentation with ICH was associated with the presence of a coexisting aneurysm at CPMC (odds ratio 1.8, 95% confidence interval 1.0 to 3.0, P=0.044). The opposite trend was observed at UCSF (odds ratio 0.4, 95% confidence interval 0.2 to 1.1, P=0.085). We observed an interaction by site involving the association between ICH presentation and aneurysm (P=0.016).
  
  
  CONCLUSIONS
  Although many BAVM characteristics were similar at the referral centers studied, the association between initial presentation with ICH and coexisting aneurysms was not. This heterogeneity between populations undermines the validity of inferences on the role of aneurysms from any single referral series, and emphasizes the complexity in creating BAVM risk-stratification models that incorporate aneurysms.
authors.affiliation: Departments of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94110, USA.
authors.forename: Alexander X
authors.initials: AX
authors.lastname: Halim
authors.forename: Vineeta
authors.initials: V
authors.lastname: Singh
authors.forename: S Claiborne
authors.initials: SC
authors.lastname: Johnston
authors.forename: Randall T
authors.initials: RT
authors.lastname: Higashida
authors.forename: Christopher F
authors.initials: CF
authors.lastname: Dowd
authors.forename: Van V
authors.initials: VV
authors.lastname: Halbach
authors.forename: Michael T
authors.initials: MT
authors.lastname: Lawton
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Gress
authors.forename: Charles E
authors.initials: CE
authors.lastname: McCulloch
authors.forename: William L
authors.initials: WL
authors.lastname: Young
mesh_terms: D000328:Adult; D002533:Cerebral Angiography; D002536:Cerebral Arteries / Q000002:abnormalities / Q000000981:diagnostic imaging; D002543:Cerebral Hemorrhage / Q000175:diagnosis* / Q000453:epidemiology; D002550:Cerebral Veins / Q000002:abnormalities / Q000000981:diagnostic imaging; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000453:epidemiology; D002538:Intracranial Arteriovenous Malformations / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D015999:Multivariate Analysis; D009518:New York / Q000453:epidemiology; D016017:Odds Ratio; D011446:Prospective Studies; D012017:Referral and Consultation; D018570:Risk Assessment; D012495:San Francisco / Q000453:epidemiology