title: Serum brain-derived neurotrophic factor levels and personality traits in patients with major depression.
abstract: BACKGROUND
  Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors. Previous studies have demonstrated lower serum BDNF levels in patients with major depressive disorder (MDD) and reported an association between BDNF levels and depression-related personality traits in healthy subjects. The aim of the present study was to explore for a possible association between peripheral BDNF levels and personality traits in patients with MDD.
  
  
  METHODS
  In this cross-sectional study, a total of 123 inpatients with MDD (Diagnostic and Statistical Manual for Mental Disorders, 4th edition) at the Juntendo University Koshigaya Hospital were recruited. Serum levels of BDNF were measured. Personality traits were assessed using the 125-item short version of the Temperament and Character Inventory (TCI).
  
  
  RESULTS
  Multiple regression analysis adjusted for age, sex, body mass index, dose of antidepressant, and depression severity showed that TCI Self-Directedness (SD) scores were negatively associated with serum BDNF levels (β = -0.23, p = 0.026).
  
  
  CONCLUSIONS
  MDD patients who have low SD did not show the reduction in serum BDNF levels that is normally associated with depressive state. Our findings suggest that depression-related biological changes may not occur in these individuals.
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. hnomoto@juntendo.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nomoto
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. hbaba@juntendo.ac.jp.|Juntendo University Mood Disorder Project (JUMP), Department of Psychiatry, Juntendo University Koshigaya Hospital, 560 Fukuroyama, 343-0032, Koshigaya, Saitama, Japan. hbaba@juntendo.ac.jp.
authors.forename: Hajime
authors.initials: H
authors.lastname: Baba
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. esatomu@juntendo.ac.jp.
authors.forename: Emi
authors.initials: E
authors.lastname: Satomura
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. hitoshim@juntendo.ac.jp.|Juntendo University Mood Disorder Project (JUMP), Department of Psychiatry, Juntendo University Koshigaya Hospital, 560 Fukuroyama, 343-0032, Koshigaya, Saitama, Japan. hitoshim@juntendo.ac.jp.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Maeshima
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. nuemura@juntendo.ac.jp.|Juntendo University Mood Disorder Project (JUMP), Department of Psychiatry, Juntendo University Koshigaya Hospital, 560 Fukuroyama, 343-0032, Koshigaya, Saitama, Japan. nuemura@juntendo.ac.jp.
authors.forename: Naoko
authors.initials: N
authors.lastname: Takebayashi
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. yukia@juntendo.ac.jp.|Juntendo University Mood Disorder Project (JUMP), Department of Psychiatry, Juntendo University Koshigaya Hospital, 560 Fukuroyama, 343-0032, Koshigaya, Saitama, Japan. yukia@juntendo.ac.jp.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Namekawa
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. psuzukit@juntendo.ac.jp.|Juntendo University Mood Disorder Project (JUMP), Department of Psychiatry, Juntendo University Koshigaya Hospital, 560 Fukuroyama, 343-0032, Koshigaya, Saitama, Japan. psuzukit@juntendo.ac.jp.
authors.forename: Toshihito
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Psychiatry, Juntendo University, School of Medicine, 2-1-1 Hongo, Tokyo, Bunkyo-ku, Japan. heii@juntendo.ac.jp.
authors.forename: Heii
authors.initials: H
authors.lastname: Arai
mesh_terms: D000928:Antidepressive Agents / Q000627:therapeutic use*; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D002605:Character; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000097:blood / Q000175:diagnosis / Q000188:drug therapy / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D010551:Personality / Q000502:physiology*; D010555:Personality Inventory; D012044:Regression Analysis; D013694:Temperament / Q000502:physiology
chemical_list: D000928:Antidepressive Agents; D019208:Brain-Derived Neurotrophic Factor