BDNF serum concentrations in first psychotic episode drug-naive schizophrenic patients: Associations with personality and BDNF Val66Met polymorphism

Aims: To investigate the relationship among brain derived neurotrophic factor (BDNF) serum concentrations, BDNF Val66Met polymorphism and personality profile in drug-naive schizophrenic patients with first-episode psychosis (FEP) and healthy participants. Main methods: This cross-sectional study included fifty FEP patients and fifty healthy participants who served as controls. To study their personality profile the standardized Greek version of the Alternative Five-Factor Zuckerman-Kuhlman Personality Questionnaire (ZXPQ) was administered. Serum BDNF levels were measured and genotyping of BDNF Val66Met polymorphism was performed in patients and healthy subjects. Key findings: FEP patients presented lower BDNF serum concentrations (P=0.002) and higher scores in ZKPQ Neuroticism (P=0.001) and Aggression-Hostility (P=0.002) scales while lower scores in the ZKPQ Sociability scale (P<0.001) than healthy participants. Multivariate analysis revealed that the odds of being assessed with FEP were 0.4 times lower in those with higher BDNF values (P<0.001) and 1.8 times greater in those with higher Neuroticism scores (P<0.001). There were no significant differences with respect to the Val66Met polymorphism between patients and healthy participants. Significance: Reduced BDNF serum concentrations along with higher Neuroticism scores might be associated with FEP. A complex interplay between BDNF serum concentrations, personality traits, BDNF Val66Met polymorphism, and psychotic symptomatology has been arisen but further investigation is needed to better clarify the observed associations. (C) 2013 Elsevier Inc. All rights reserved.