title: Brain-derived neurotrophic factor Val66Met polymorphism predicts worse functional outcome after surgery in patients with unruptured brain arteriovenous malformation.
abstract: OBJECTIVE
  The Val66Met polymorphism of brain-derived neurotrophic factor is associated with decreased brain-derived neurotrophic factor secretion and poor outcome after acute neurological injury. We hypothesized that the Met allele is associated with worsening of functional outcome after brain arteriovenous malformation resection.
  
  
  METHODS
  Three hundred forty-one surgically treated patients with brain arteriovenous malformation with outcome data were genotyped for Val66Met. Outcome was change in modified Rankin Scale preoperatively versus postoperatively, dichotomized into poor (change >0) or good outcome (change ≤0). Likelihood ratio tests for interactions and logistic regression analysis were performed.
  
  
  RESULTS
  A significant interaction (P=0.03) of Val66Met genotype and hemorrhagic presentation existed; thus, ruptured and unruptured patients were considered separately. The Met allele was associated with increased risk of poor outcome among patients presenting unruptured (OR, 2.15; 95% CI, 1.02-4.55; P=0.045) but not ruptured (OR, 0.54; 95% CI, 0.19-1.53; P=0.25), adjusting for covariates.
  
  
  CONCLUSIONS
  The Val66Met polymorphism is associated with worsened surgical outcome in patients with unruptured brain arteriovenous malformation, a group that currently has no good risk predictors. Further studies replicating these findings are needed.
authors: Center for Cerebrovascular Research, Department of Anesthesia and Perioperative Care, University of California, San Francisco, San Francisco, CA 94110, USA.
authors: Erick M
authors: EM
authors: Westbroek
authors: Ludmila
authors: L
authors: Pawlikowska
authors: Michael T
authors: MT
authors: Lawton
authors: Charles E
authors: CE
authors: McCulloch
authors: William L
authors: WL
authors: Young
authors: Helen
authors: H
authors: Kim
mesh_terms: D000328:Adult; D000483:Alleles; D019943:Amino Acid Substitution; D000704:Analysis of Variance; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000235:genetics* / Q000601:surgery*; D016015:Logistic Models; D008297:Male; D008715:Methionine / Q000235:genetics; D008875:Middle Aged; D019635:Neurosurgical Procedures; D011110:Polymorphism, Genetic / Q000235:genetics; D011237:Predictive Value of Tests; D012422:Rupture, Spontaneous / Q000473:pathology; D016896:Treatment Outcome; D014633:Valine / Q000235:genetics
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D008715:Methionine; D014633:Valine