title: Increased BDNF levels after electroconvulsive therapy in patients with major depressive disorder: A meta-analysis study.
abstract: We performed a systematic review and meta-analysis to estimate brain-derived neurotrophic factor (BDNF) level in patients with major depressive disorder (MDD) after electroconvulsive therapy (ECT).
  
  
  
  A comprehensive search of the Cochrane Library, MEDLINE, LILACS, Grey literature, and EMBASE was performed for papers published from January 1990 to April 2016. The following key terms were searched: "major depressive disorder", "unipolar depression", "brain-derived neurotrophic factor", and "electroconvulsive therapy".
  
  
  
  A total of 252 citations were identified by the search strategy, and nine studies met the inclusion criteria of the meta-analysis. BDNF levels were increased among patients with MDD after ECT (P value = 0.006). The standardized mean difference was 0.56 (95% CI: 0.17-0.96). Additionally, we found significant heterogeneity between studies (I2= 73%).
  
  
  
  Our findings suggest a potential role of BDNF as a marker of treatment response after ECT in patients with MDD.
authors.affiliation: Laboratório de Epidemiologia, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Programa de Pós-Graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: Renan Boeira
authors.initials: RB
authors.lastname: Rocha
authors.affiliation: Laboratório de Epidemiologia, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: Eduardo Ronconi
authors.initials: ER
authors.lastname: Dondossola
authors.affiliation: Laboratório de Epidemiologia, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Programa de Pós-graduação em Saúde Coletiva, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: Antônio José
authors.initials: AJ
authors.lastname: Grande
authors.affiliation: Laboratório de Epidemiologia, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Programa de Pós-Graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: Tamy
authors.initials: T
authors.lastname: Colonetti
authors.affiliation: Programa de Pós-graduação em Saúde Coletiva, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: Luciane Bisognin
authors.initials: LB
authors.lastname: Ceretta
authors.affiliation: UT Center of Excellence on Mood Disorder, Department of Psychiatry and Behavioral Sciences, The University of Texas Science Center at Houston, Houston, TX, USA; Bipolar Disorder Program, Laboratory of Molecular Psychiatry, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil.
authors.forename: Ives C
authors.initials: IC
authors.lastname: Passos
authors.affiliation: Programa de Pós-Graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; UT Center of Excellence on Mood Disorder, Department of Psychiatry and Behavioral Sciences, The University of Texas Science Center at Houston, Houston, TX, USA; Translational Psychiatry Program, Department of Psychiatry and Behavioral Sciences, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA; Neuroscience Graduate Program, The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX, USA.
authors.forename: Joao
authors.initials: J
authors.lastname: Quevedo
authors.affiliation: Laboratório de Epidemiologia, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Programa de Pós-Graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Programa de Pós-graduação em Saúde Coletiva, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil. Electronic address: mir@unesc.net.
authors.forename: Maria Inês
authors.initials: MI
authors.lastname: da Rosa
mesh_terms: D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism*; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D003865:Major Depressive Disorder / Q000378:metabolism* / Q000628:therapy*; D004565:Electroconvulsive Therapy / Q000379:methods*; D006801:Humans
chemical_list: D019208:Brain-Derived Neurotrophic Factor
keywords: BDNF; Electroconvulsive therapy; Major depressive disorder; Meta-analysis