Lower Brain-Derived Neurotropic Factor Levels in Untreated Adolescents With First-Episode Psychosis.

OBJECTIVE: Brain-derived neurotropic factor (BDNF) is known to play a role in the pathogenesis of schizophrenia. However, the relationship between early onset schizophrenia and BDNF has not been extensively studied. The aim of the study was to compare the levels of BDNF between adolescent patients with first-episode psychosis (FEP) and the healthy control subjects.

METHOD: The study was conducted in the Department of Child Psychiatry at Dicle University. A total of 26 adolescent patients aged between 11 and 17 years who had not received previous therapy and whose conditions were diagnosed with psychosis according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and 26 age- and sex-matched healthy adolescent control subjects were included. Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version, and the Positive and Negative Symptom Scale were conducted with all participants. The clinical global impression was used to evaluate disease severity. The BDNF levels were measured in the serum by enzyme-linked immunosorbent assay method.

RESULTS: The mean (SD) age was 14.6 (1.6) years in both FEP group (male/female, 11/15) and the control group (P > 0.05). The FEP group had significantly lower serum BDNF levels (2.0 ± 1.9 ng/mL) compared with the control group (3.4 ± 3.0 ng/mL, P = 0.03). There was no significant relationship between BDNF concentration and the Positive and Negative Symptom Scale (positive and negative scores) scores (r = -0.14, P = 0.74 and r = 0.49, P = 0.22, respectively). There was no significant relationship between the duration of untreated psychosis and serum BDNF levels (r = -0.22, P = 0.32).

CONCLUSIONS: High incidence of schizophrenia in patients with FEP suggests a relationship between BDNF levels and the pathogenesis of schizophrenia. We suggest that BDNF may be a useful neurobiological marker of early onset schizophrenia.