title: Outcome after conservative management or intervention for unruptured brain arteriovenous malformations.
abstract: OBJECTIVE
  Whether conservative management is superior to interventional treatment for unruptured brain arteriovenous malformations (bAVMs) is uncertain because of the shortage of long-term comparative data.
  
  
  OBJECTIVE
  To compare the long-term outcomes of conservative management vs intervention for unruptured bAVM.
  
  
  METHODS
  Population-based inception cohort study of 204 residents of Scotland aged 16 years or older who were first diagnosed as having an unruptured bAVM during 1999-2003 or 2006-2010 and followed up prospectively for 12 years.
  
  
  METHODS
  Conservative management (no intervention) vs intervention (any endovascular embolization, neurosurgical excision, or stereotactic radiosurgery alone or in combination).
  
  
  METHODS
  Cox regression analyses, with multivariable adjustment for prognostic factors and baseline imbalances if hazards were proportional, to compare rates of the primary outcome (death or sustained morbidity of any cause by Oxford Handicap Scale [OHS] score ≥2 for ≥2 successive years [0 = no symptoms and 6 = death]) and the secondary outcome (nonfatal symptomatic stroke or death due to bAVM, associated arterial aneurysm, or intervention).
  
  
  RESULTS
  Of 204 patients, 103 underwent intervention. Those who underwent intervention were younger, more likely to have presented with seizure, and less likely to have large bAVMs than patients managed conservatively. During a median follow-up of 6.9 years (94% completeness), the rate of progression to the primary outcome was lower with conservative management during the first 4 years of follow-up (36 vs 39 events; 9.5 vs 9.8 per 100 person-years; adjusted hazard ratio, 0.59; 95% CI, 0.35-0.99), but rates were similar thereafter. The rate of the secondary outcome was lower with conservative management during 12 years of follow-up (14 vs 38 events; 1.6 vs 3.3 per 100 person-years; adjusted hazard ratio, 0.37; 95% CI, 0.19-0.72).
  
  
  CONCLUSIONS
  Among patients aged 16 years or older diagnosed as having unruptured bAVM, use of conservative management compared with intervention was associated with better clinical outcomes for up to 12 years. Longer follow-up is required to understand whether this association persists.
authors.affiliation: Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland.
authors.forename: Rustam
authors.initials: R
authors.lastname: Al-Shahi Salman
authors.affiliation: Institute for Ageing and Health, Newcastle University, Newcastle-upon-Tyne, England.
authors.forename: Philip M
authors.initials: PM
authors.lastname: White
authors.affiliation: Division of Applied Health Sciences, University of Aberdeen, Aberdeen, Scotland.
authors.forename: Carl E
authors.initials: CE
authors.lastname: Counsell
authors.affiliation: Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland.
authors.forename: Johann
authors.initials: J
authors.lastname: du Plessis
authors.affiliation: Department of Neurosurgery, Leiden University Medical Center, Leiden, the Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: van Beijnum
authors.affiliation: Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Colin B
authors.initials: CB
authors.lastname: Josephson
authors.affiliation: Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland.
authors.forename: Tim
authors.initials: T
authors.lastname: Wilkinson
authors.affiliation: University College London Institute for Global Health, London, England.
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Wedderburn
authors.affiliation: Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland.
authors.forename: Zoe
authors.initials: Z
authors.lastname: Chandy
authors.affiliation: Institute of Neurological Sciences, Southern General Hospital, Glasgow, Scotland.
authors.forename: E Jerome
authors.initials: EJ
authors.lastname: St George
authors.affiliation: Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland.
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Sellar
authors.affiliation: Division of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Warlow
mesh_terms: D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D016634:Radiosurgery; D012606:Scotland; D016019:Survival Analysis; D016896:Treatment Outcome; D057832:Watchful Waiting