Evaluation the levels of serum growth factors, galanin and the factors that may be related to them in children aged 6-12 years diagnosed with attention deficit hyperactivity disorder

Although attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disorder in childhood, its etiology has not been fully elucidated yet. In our study, it was aimed to investigate the levels of serum brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), glial cell-derived neurotrophic factor (GDNF) and galanin in children and adolescents diagnosed with ADHD and to compare the findings with healthy controls. Our sample was composed of 58 ADHD aged 6-12 years and 60 healthy control cases. During diagnostic evaluation, along with DSM-5 criteria, Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version-Turkish Version applied to all cases. Sociodemographic data form, DSM-IV-Based Child and Adolescent Behavioral Disorders Screening and Rating Scale, Conners' Parent/Teacher Rating Scale-Revised Long Form, Child Depression Inventory, State-Trait Anxiety Inventory for Children applied. All cases included in the study were evaluated in terms of serum BDNF, NGF, GDNF and galanin levels at baseline. Then, methylphenidate treatment was started and ADHD cases were reevaluated in terms of serum BDNF, NGF, GDNF and galanin levels in the tenth week of treatment. In the ADHD group baseline levels of serum BDNF, NGF, GDNF and galanin were found significantly higher than healthy controls. However, post-treatment levels of serum BDNF, NGF, GDNF and galanin were found significantly lower compared to baseline levels. There was no correlation between scale scores and levels of serum BDNF, NGF, GDNF and galanin. As a result of our study, it is thought that serum growth factors and galanin are worth evaluating parameters in patients with ADHD. Further studies with longer-term treatments and larger sample groups are required for to elucidate the etiopathogenesis of ADHD and neurochemical processes that change with treatment. Keywords: Attention deficit hyperactivity disorder, BDNF, NGF, GDNF, galanin