title: Decreased Brain-Derived Neurotrophic Factor in Older Adults with Bipolar Disorder.
abstract: Decreased levels of brain derived neurotrophic factor (BDNF) have been found in adult patients with bipolar disorder (BD) compared with a comparison group, yet there are no data specifically examining this in geriatric patients. The objective of this study was to examine whether euthymic late-life BD patients have lower BDNF levels than healthy comparators.
  
  
  
  Cross-sectional study.
  
  
  
  Clinics at the University of Pittsburgh and the Centre for Addiction and Mental Health (Toronto).
  
  
  
  Older patients with BD (age ≥50 years, N = 118) and similarly aged healthy comparators (N = 76). There were both BD type I (N = 91) and type II (N = 27) patients.
  
  
  
  Serum BDNF levels were assessed in BD patients and healthy comparators.
  
  
  
  We found lower levels of BDNF in patients with BD than in healthy comparators (9.0 ± 6.2 versus 12.3 ± 8.9 pg/µg, t(192) = -3.01, p = 0.002), which remained even after controlling for age, sex, lithium use, and site (F(1,176) = 4.32, p = 0.039). This decrease was found specifically in patients with BD type I (8.0 ± 5.5 versus 12.3 ± 8.9 pg/µg, t(165) = 3.7, Bonferroni p < 0.001), but not type II (12.0 ± 7.5 versus 12.3 ± 8.9 pg/µg, t(101) = 0.14, Bonferroni p = 1.0).
  
  
  
  Older patients with BD have lower serum levels of BDNF compared with similarly aged comparators. These effects appear to be specific to patients with BD type I. Future studies are needed to investigate the impact of reduced BDNF levels on cognition, mood, and other aspects of BD throughout the life course.
authors.affiliation: Department of Internal Medicine, Geriatrics Discipline, University of Sao Paulo, Brazil.
authors.forename: Aline T
authors.initials: AT
authors.lastname: Soares
authors.affiliation: Department of Psychiatry, University of Toronto, Canada; Department of Pharmacology, University of Toronto, Canada; Department of Psychiatry, Centre for Addiction and Mental Health, Toronto, Canada. Electronic address: ana.andreazza@utoronto.ca.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Andreazza
authors.affiliation: Department of Psychiatry, University of Toronto, Canada; Department of Psychiatry, Centre for Addiction and Mental Health, Toronto, Canada.
authors.forename: Soham
authors.initials: S
authors.lastname: Rej
authors.affiliation: Department of Psychiatry, University of Toronto, Canada; Department of Psychiatry, Centre for Addiction and Mental Health, Toronto, Canada.
authors.forename: Tarek K
authors.initials: TK
authors.lastname: Rajji
authors.affiliation: Department of Psychiatry, University of Pittsburgh, PA, USA.
authors.forename: Ariel G
authors.initials: AG
authors.lastname: Gildengers
authors.affiliation: Department of Psychiatry, University of Sao Paulo, Brazil.
authors.forename: Beny
authors.initials: B
authors.lastname: Lafer
authors.affiliation: Department of Psychiatry, University of Toronto, Canada; Department of Pharmacology, University of Toronto, Canada; Department of Psychiatry, Centre for Addiction and Mental Health, Toronto, Canada.
authors.forename: L Trevor
authors.initials: LT
authors.lastname: Young
authors.affiliation: Department of Psychiatry, University of Toronto, Canada; Department of Psychiatry, Centre for Addiction and Mental Health, Toronto, Canada.
authors.forename: Benoit H
authors.initials: BH
authors.lastname: Mulsant
mesh_terms: D000368:Aged; D000375:Aging / Q000097:blood*; D001714:Bipolar Disorder / Q000097:blood* / Q000188:drug therapy; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008094:Lithium / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009864:Ontario; D010414:Pennsylvania; D011569:Psychiatric Status Rating Scales
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D008094:Lithium
keywords: aging; bipolar disorder; brain-derived neurotrophic factor; elderly