Interaction Between Childhood Trauma and BDNF Influences Clinical Symptoms in First-Episode Schizophrenia

Background: Schizophrenia (SZ), a complex psychiatric disorder affecting ~1% of the population, involves gene-environment interactions. This study investigates how BDNF gene polymorphisms and childhood trauma jointly influence clinical symptoms in first-episode SZ patients. Methods: Employing a case-control design, 93 first-episode SZ patients and 64 healthy controls were assessed using the Childhood Trauma Questionnaire (CTQ) and Positive and Negative Syndrome Scale (PANSS). BDNF polymorphisms (rs6265, rs2030324 and rs11030101) were analyzed. Generalized linear models (SPSS 20.0) evaluated interactions between genetic variants and trauma, adjusting for demographics and clinical variables. Results : SZ patients exhibited significantly higher CTQ scores in emotional neglect (EN), physical abuse (PA), emotional abuse (EA), sexual abuse (SA), physical neglect (PN), and total trauma (all P <0.05). EN, PA, PN, and total CTQ positively correlated with positive symptoms (r=0.250–0.286), while EA correlated with excitement/hostility (r=0.221). Trauma subtypes (EN, EA, SA, PN, total CTQ) also linked to depression/anxiety (r=0.213–0.384). Genetic interactions revealed rs6265 (CT/TT) with PN inversely associated with anxiety-depression ( P <0.05), whereas rs11030101 (TA) interacted with SA to elevate anxiety-depression and inversely correlated PN/total CTQ with negative symptoms. Conclusion: First-episode SZ patients report higher childhood trauma exposure than controls, with trauma severity strongly linked to positive, excitement-hostility, and depression-anxiety symptoms. BDNF polymorphisms modulate trauma’s effects: rs6265-PN interactions mitigate anxiety-depression, while rs11030101-SA interactions exacerbate it. These findings highlight gene-environment interplay in SZ pathogenesis, emphasizing BDNF’s role in shaping trauma-related symptom profiles.