title: The Met allele of the BDNF Val66Met polymorphism predicts poor outcome among survivors of aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  Brain-derived neurotrophic factor (BDNF) plays a role in neuronal survival, plasticity and neurogenesis. The BDNF gene contains a common Val66Met polymorphism; the Met allele is associated with lower depolarization-induced BDNF release and differences in memory functions and brain morphology. We hypothesized that the Met allele is associated with poor recovery from subarachnoid hemorrhage.
  
  
  METHODS
  A sample of 105 survivors was assessed at 3 months after subarachnoid hemorrhage using Glascow Outcome Scale. Poor outcome was defined as severe disability or worse. DNA samples were genotyped for the Val66Met polymorphism.
  
  
  RESULTS
  Higher percentage of the Met carriers had a poor outcome (29%) as compared with the Val/Val group (10%; P=0.011). In multiple logistic regression, this association between the Met allele and poor outcome was independent of several other prognostic factors such as patient age, clinical condition, and radiological severity of the bleeding (odds ratio 8.40; 95% CI, 1.60 to 44.00; P=0.012).
  
  
  CONCLUSIONS
  Genetically influenced variation in BDNF function plays a role in recovery from subarachnoid hemorrhage. These data indicate that augmentation of BDNF signaling may be beneficial to recovery from brain injury.
authors.forename: Jari
authors.initials: J
authors.lastname: Siironen
authors.forename: Seppo
authors.initials: S
authors.lastname: Juvela
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Kanarek
authors.forename: Juhani
authors.initials: J
authors.lastname: Vilkki
authors.forename: Juha
authors.initials: J
authors.lastname: Hernesniemi
authors.forename: Jaakko
authors.initials: J
authors.lastname: Lappalainen
mesh_terms: D000328:Adult; D000483:Alleles; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008715:Methionine / Q000235:genetics; D008875:Middle Aged; D011110:Polymorphism, Genetic; D011237:Predictive Value of Tests; D020127:Recovery of Function; D013345:Subarachnoid Hemorrhage / Q000235:genetics* / Q000503:physiopathology*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D008715:Methionine