Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Aug 6, 2022; 10(22): 7749-7759
Published online Aug 6, 2022. doi: 10.12998/wjcc.v10.i22.7749
Serum ferritin levels in children with attention deficit hyperactivity disorder and tic disorder
Cai-Yun Tang, Fang Wen
Cai-Yun Tang, Fang Wen, Department of Psychiatry, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing 100045, China
Author contributions: Wen F gave suggestions for writing, analysis and revised the manuscript; Tang CY did substantial contributions to the conception and design of the work; and the acquisition, analysis, or interpretation of data for the work and drafted the manuscript.
Institutional review board statement: This study was in accordance with the Declaration of Helsinki and approved by the Institutional Ethics Committee of Beijing Children's Hospital, No. IEC-C-006-A04-V.06.
Conflict-of-interest statement: All of the authors declare that they have no competing interests.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at wenfang0812@163.com. Participants gave informed consent for data sharing, but the presented data are anonymized and risk of identification is low. No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Fang Wen, MM, Chief Doctor, Department of Psychiatry, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, No. 56 Nanlishi Road, Beijing 100045, China. wenfang0812@163.com
Received: February 8, 2022
Peer-review started: February 8, 2022
First decision: March 23, 2022
Revised: May 1, 2022
Accepted: June 27, 2022
Article in press: June 27, 2022
Published online: August 6, 2022
Processing time: 164 Days and 0.2 Hours
ARTICLE HIGHLIGHTS
Research background

Iron deficiency in early childhood can lead to developmental abnormalities in gene expression, neurotransmitter function, neurometabolism and other aspects related to brain development. it has been reported that iron deficiency in children is associated with neurodevelopmental diseases. Serum ferritin is one of the most reliable and widely used markers of iron storage status in the body. This study will explore the current status of iron deficiency in children with neurodevelopmental disorders and its influence on sex and age, providing an important reference for the correlation between neurodevelopmental disorders and ferritin and necessary iron supplementation.

Research motivation

The level of iron deficiency in neurodevelopmental disorders of attention deficit disorder hyperactivity (ADHD), tic disorder (TD) and autism spectrum disorders (ASD) and the status of sex-age effects are still unclear, and data from Chinese samples are lacking. This study will adopt the thinking of retrospective research and investigation by enrolling ADHD, TD and ASD children in the psychiatric department of Beijing Children's Hospital as the sample. The sample size is large, and more attention can be paid to the comparison of the difference in serum ferritin levels of ADHD, TD and ASD children with respect to gender and age than previous studies.

Research objectives

This study will explore the current status of iron deficiency in children with neurodevelopmental disorders and its influence on sex and age, providing an important reference for the correlation between neurodevelopmental disorders and ferritin and necessary iron supplementation.

Research methods

A total of 1565 children with ADHD, 1694 children with TD, 93 children with ASD and 1997 healthy control children were included between January 1, 2020, and December 31, 2021 at Beijing Children's Hospital. We describe the differences in age levels and ferritin levels between different disease groups and their sex differences. T test, Chi-square analysis, variance analysis and regression analysis were used for statistical processing of the data.

Research results

The average serum ferritin levels of male and female children were 36.82 ± 20.64 μg/L and 35.64 ± 18.56 μg/L in 1565 ADHD patients. The average serum ferritin levels of male and female children were 35.72 ± 20.15 μg/L and 34.54 ± 22.12 μg/L in 1694 TD patients. As age increased, the incidence of low serum ferritin in ADHD and TD first decreased and then increased, and 10 years old was the turning point of rising levels. The incidence of ADHD with low serum ferritin was 8.37%, the incidence of TD with low serum ferritin was 11.04%, and the incidence of the healthy control group with low serum ferritin was 8.61% (P < 0.05). There may be some selection bias and confounding factors such as diet, environmental factors and family history in the sample, and our study cannot prove a causal relationship between low serum ferritin and neurodevelopmental disease.

Research conclusions

Neurodevelopmental disorders (ADHD, TD and ASD) are heterogeneous diseases. We found that the incidence of low serum ferritin levels in children with ADHD and TD between 5-12 years old was 8.37% and 11.04%, respectively. The incidence of ASD with low serum ferritin was 15.05%. It is recommended to routinely check the serum ferritin levels and related hematological indicators of children with ADHD, TD and ASD and to perform necessary iron supplementation. In particular, children with ADHD and TD aged 5-10 years were diagnosed.

Research perspectives

In the future, we need to conduct cohort studies to further consolidate the evidence of iron deficiency in children with ADHD, TD and ASD and carry out necessary iron intervention studies to explore the underlying mechanisms.