Introduction : Attention-Deficit/Hyperactivity Disorder (ADHD) is a disorder that occurs during childhood development, which presents with signs of reduced attention and hyperactivity [1]. Necessary nutrients, such as trace minerals, including manganese, iron, zinc, iodine, selenium, copper, and chromium, are associated with changes in neuronal function that can lead to adverse effects on behavior and learning [2]. In addition to these, social, emotional, behavioral problems, and cognitive impairments such as executive dysfunctions are common in ADHD [3]. Goal: To evaluate the hair elements and intelligence quotient in children with ADHD. Materials and Methods: This is a cross-sectional comparative study conducted at elementary schools of Ulaanbaatar city. All in all 60 children of both genders aged between 7-12 years old were included in the study. Children were divided into two groups as children with ADHD group and a control group. Each group had 30 children. For assessment of emotional Intelligence EQ-i:YV - Emotional Quotient Inventory: Youth Version (Bar-On & Parker, 2000; it ad. Sannio Fancello, & Cianchetti, 2012) was used. Scalp hair samples were randomly collected from approximately ten sites around both sides of posterior parietal eminences and external occipital protuberance. Samples were then packed at room temperature and submitted for laboratory analysis. The study was approved by the Research Ethics Committee of Mongolian National University of Medical Sciences (Reg. No. 2018/Д-10). Results: The IQ of children with ADHD group were 85.03±16.86 p<.0001 and the IQ of control group =108.9±21.22, p<.0001. We identified hair minerals such as Mg, Zn, Pb, Se, Mn. We have then compared to each group and normal ranges of ages. ADHD group and the control group had Pb concentration that was slightly higher and inversely Mg concentration was slightly lower (r=-0.502, p=.005). Concentration of Pb, IQ were directly opposite (r=-0.38, p=.03). Conclusion
1. IQ was lower in the ADHD group compared to control group 85.03±16.86 p<.0001, monitored group 108.9±21.22, p<.0001.
2. The group with ADHD had lower Mg, Zn, and higher Pb, Se, Mn (p<.0001). The IQ decreased when there was increased Pb and decreased Mg.