title: Brain-derived neurotrophic factor increase during treatment in severe mental illness inpatients.
abstract: Meta-analytical evidence suggests that brain-derived neurotrophic factor (BDNF) is altered in various psychiatric disorders. However, meta-analyses may be hampered by the heterogeneity of BDNF assays, lack of BDNF standard values and heterogeneity among the populations included in the studies. To address these issues, our study aimed to test, in a 'true-to-life' setting, the hypothesis that the serum BDNF level is nonspecifically reduced in acute severe mental illness (SMI) patients and increases during inpatient treatment. Consecutive samples of 236 inpatients with SMI and 100 healthy controls were recruited. SMI includes schizophrenia and severe mood disorders, and is characterized in the sample by the presence of at least 2 years of psychiatric treatment and disability. Generalized estimating equations were used to analyze BDNF serum levels at admission and upon discharge controlled by confounding factors. BDNF levels increased significantly between admission and discharge in SMI patients. BDNF levels showed significant reductions compared with controls both at admission and upon discharge. In addition, BDNF levels showed no difference among SMI patient diagnostic subgroups (unipolar depression, bipolar depression, schizophrenia and manic episode). The increase but non-restoration of BDNF levels, even with the general acute improvement of clinical scores, may reflect the progression of the disorder characteristically seen in these patients. BDNF levels could be considered as a marker for the presence of a nonspecific psychiatric disorder and possibly a transdiagnostic and nonspecific marker of disease activity.
authors.affiliation: Hospital de Clínicas de Porto Alegre, Postgraduate Program in Medical Sciences: Psychiatry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: G L
authors.initials: GL
authors.lastname: Nuernberg
authors.affiliation: Laboratory of Molecular Psychiatry, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors.forename: B
authors.initials: B
authors.lastname: Aguiar
authors.affiliation: Laboratory of Molecular Psychiatry, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
authors.forename: G
authors.initials: G
authors.lastname: Bristot
authors.affiliation: Hospital de Clínicas de Porto Alegre, Postgraduate Program in Medical Sciences: Psychiatry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: M P
authors.initials: MP
authors.lastname: Fleck
authors.affiliation: Hospital de Clínicas de Porto Alegre, Postgraduate Program in Medical Sciences: Psychiatry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: N S
authors.initials: NS
authors.lastname: Rocha
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000097:blood / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D001938:Brazil; D003865:Major Depressive Disorder / Q000097:blood / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D005260:Female; D005500:Follow-Up Studies; D006760:Hospitalization; D006769:Hospitals, General; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000097:blood* / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011567:Psychiatric Department, Hospital; D012559:Schizophrenia / Q000097:blood / Q000175:diagnosis / Q000628:therapy; D012565:Schizophrenic Psychology
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human