Investigation of intestinal microbiota of children with attention deficit hyperactivity disorder and healthy children

Purpose: Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that begins in childhood and is characterized by inattention, hyperactivity, and impulsivity. Its pathophysiology has not been fully elucidated. There is growing evidence that the gut microbiota may play a role in the development of this disorder. A study investigating the relationship between ADHD and gut microbiota in Turkey has not been published yet. This study aimed to determine the gut microbiota of children with ADHD and healthy children, as well as the differences between them, and to examine the dietary and sleep habits of these children. Materials and Methods: The research was conducted between December 2022 and November 2023 at the Child and Adolescent Psychiatry Outpatient Clinic of Manisa Celal Bayar University. The study consisted of children aged 6-12 years diagnosed with ADHD during interviews conducted using the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL) and children without any diagnosis. Sleep and eating habits were evaluated using the 2nd Level Sleep Disorder Short For and the The Children's Eating Behavior Inventory along with a sociodemographic form. Gut microbiota analysis in this study was performed using 16S NGS Metagenome Analysis. Results: In this study, it was found that the education level of the mothers of children in the ADHD group was significantly lower compared to the mothers in the control group. The values of Shannon and Simpson Diversity Indexes were significantly lower in the ADHD group compared to the control group. Although there was a percentage difference, there was no statistically significant difference between the groups in terms of species, genus, family, order, class and phylum. When sleep and eating habit scale scores were evaluated, no statistically significant difference was found between the groups. Conclusion: It was understood that the biodiversity of the gut microbiota was decreased in the ADHD group. Our study supports the evidence that gut microbiota plays a role in the pathogenesis of ADHD. It is believed that larger samples and further studies could help understand the pathogenesis of ADHD.