The relationship between antioxidants and inflammation in children with attention deficit hyperactivity disorder

Abstract

Introduction: Recent studies have identified Attention Deficit Hyperactivity Disorder (ADHD) as an inflammatory condition associated with immunological and oxidative responses. Therefore, it is necessary to examine these processes in these patients. The present study aimed at investigating the relationship between the dietary intake of antioxidants, Superoxide Dismutase (SOD) activity, and the serum levels of inflammatory factors in ADHD students. Methods: This retrospective case-control study was conducted on 64 ADHD children aged 6 - 13 years. The demographic questionnaire, Food Frequency Questionnaire, and Baecke Physical Activity Questionnaire were used for data collection. SOD activity and the serum level of inflammatory factors (homocysteine, interleukin-6, and C-reactive Protein (CRP)) were measured in all patients. According to the CRP values, 32 patients were included in the case group (CRP≥1 mg/L) and 32 patients in the control group (0≤CRP<1 mg/L). Results: There was no significant difference between the two groups in age, sex, weight, height, and body mass index. In the case group, the mean SOD activity (P=0.034), the physical activity (P=0.04), zinc intake (P=0.02), and homocysteine levels were higher than the control group (P=0.001). Of all studied variables, the best predictors were homocysteine (OR: 1.34, 95% CI: 1.082-1.670, P=0.029) and physical activity (OR: 0.85, 95% CI: 0.761-0.952, P=0.022) respectively, whereas other variables were not significant predictors. Conclusion: The present study showed that the level of inflammatory factors in the case group was significantly higher than the control group. Homocysteine and physical activity can predict the inflammation status induced by CRP.