title: Brain-derived neurotrophic factor levels in first episode of psychosis: A systematic review.
abstract: OBJECTIVE
  To systematically review studies measuring peripheric brain-derived neurotrophic factor (BDNF) levels on first-episode psychosis patients and variables related to them.
  
  
  METHODS
  A systematic search was made of articles published in the Medline database from 2002 up to June 2014. Included are original studies that report enzyme-linked immunosorbent assay measurement of BDNF levels in serum or plasma in patients with a diagnosis of first episode psychosis (FEP) and age- and gender- matched healthy controls.
  
  
  RESULTS
  Of the initially identified 147 articles, only 18 satisfied the inclusion criteria. Of this, 15 found a significant reduction in patients with FEP compared with age- and gender - matched controls.
  
  
  CONCLUSIONS
  Peripheral BDNF levels are generally reduced in FEP patients. There are some factors that may influence BDNF levels that need to be further studied. Furthermore, a future meta-analysis in this topic is needed.
authors: Alba Toll, Anna Mané, Institut de Neuropsiquitria i Addiccions, Parc de Salut Mar, 08003 Barcelona, Spain.
authors: Alba
authors: A
authors: Toll
authors: Alba Toll, Anna Mané, Institut de Neuropsiquitria i Addiccions, Parc de Salut Mar, 08003 Barcelona, Spain.
authors: Anna
authors: A
authors: Mané
keywords: Brain-derived neurotrophic factor; Psychosis