Regulatory T cells in children with attention deficit hyperactivity disorder: A case-control study.

OBJECTIVE

The pathophysiology of attention deficit hyperactivity disorder (ADHD) are still not fully elucidated. Immune system dysregulation has emerged as a major etiological focus as a result of the high comorbidity of allergic disease, inflammatory biomarkers, and genetic research. The present study aimed to evaluate peripheral lymphocyte subpopulations and regulatory T cells (Tregs) in children with ADHD.

METHODS

This single-center cross-sectional case-control study assessed 49 children with ADHD and 35 age- and gender-matched healthy children aged 7-12 years (9.10 ± 2.37 and 9.45 ± 2.13, respectively). The participants were screened for psychopathology using the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version, while the severity of ADHD symptoms was measured by means of the distracted-Continuous Performance Test. Peripheral lymphocyte subpopulations and Tregs were analyzed with flow-cytometry.

RESULTS

There is no significant difference in peripheral blood lymphocyte subsets between ADHD and control groups The children diagnosed with ADHD exhibited significantly higher levels of CD3 CD4 CD25 Foxp3 (Tregs) than the healthy control subjects (8.23 ± 2.09 vs. 6.61 ± 2.89; z = 2.965, p = .004). The Tregs cell (Exp(B) = 1.334; p = .042; CI = 1.011-1.761) levels were determined to be statistically significant according to regression analysis and were associated with an increased probability of ADHD.

CONCLUSION

Elevated Treg levels were linked to an increased likelihood of ADHD. This study suggested that changes in immune regulatory cells represent an important part of research in treatment of ADHD.