Serum Brain-derived neurotrophic factor levels in Chinese children with autism spectrum disorders: a pilot study

Brain-derived neurotrophic factor (BDNF) plays a critical role in the pathogenesis of Autism spectrum disorders (ASD). The purpose of this study was to investigate the potential role of BDNF in Chinese children with ASD. Sixty patients (48 male, 12 female) diagnosed with ASD and 60 healthy sex and age control subjects were assessed for serum BDNF content at admission. BDNF were assayed with enzyme-linked immunosorbent assay methods, and severity of ASD was evaluated with the Childhood Autism Rating Scale (CARS) Score. The results indicated that the median serum BDNF levels were significantly (P<0.0001) higher in children with ASD as compared to normal cases [17.6(IQR: 13.7-21.4) ng/ml and 11.5(9.6-13.8) ng/ml, respectively]. Based on the receiver operating characteristic (ROC) curve, the optimal cut-off value of serum BDNF levels as an indicator for auxiliary diagnosis of autism was projected to be 15.0 ng/ml. Further, we found that an increased risk of ASD was associated with BDNF levels >15.0 ng/ml (adjusted OR 10.4, 95% CI: 4.39-29.32) after adjusting for above possible confounders. Our study demonstrated that serum BDNF levels were associated with ASD, and higher levels could be considered as an independent risk factor of ASD.