Effect of Vitamin D Supplementation on Inflammatory Biomarkers in School-Aged Children with Attention Deficit Hyperactivity Disorder

Background and Objective. Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent psychiatric and developmental disorders in children. Low serum vitamin D concentration and elevated inflammation biomarkers might be involved in neuropsychiatric disorders, such as ADHD. The purpose of this study was to evaluate the effect of vitamin D supplementation on TNF-alpha and IL-6 levels in children with attention deficit hyperactivity disorder. Method. This randomized double-blind, placebo-controlled trial was conducted on 75 school-aged children with a diagnosis of ADHD based on DSM-V criteria. Children were randomly allocated to receive either vitamin D3 (2000 IU/day) or a placebo for 3 months. Serum IL-6, TNF-alpha, and 25(OH) D were assessed before and after the intervention to determine the effects of vitamin D on the highlighted parameters. Results. Serum levels of 25(OH) D increased significantly in the vitamin D group (P=0.01). However, no significant differences in serum IL-6 and TNF-alpha were found between both groups at the baseline and at the end of the intervention. Conclusion. The findings revealed that vitamin D supplementation for 3 months is not efficacious in reducing inflammatory cytokines in children with ADHD. Further studies are required to confirm these results.