Stress/Immune Biomarkers in Saliva among Children with ADHD Status

Abstract

Background. This cross-sectional study aimed to evaluate stress and immune biomarkers in saliva samples of attention-deficit/hyperactivity disorder ADHD compared to healthy non-ADHD children. Material and methods. A total of 132 children under 11 years old (8.5 ± 1.1) enrolled in a cross-sectional study: with confirmed ADHD (n = 60) and healthy controls (n = 72). The clinical evaluation included physical measurements (height, waist, hip circumference, body weight, body mass index BMI, BMI z-score) and unstimulated saliva collection and measurements of free cortisol, salivary alpha-amylase (sAA), and secreted immunoglobulins (sIgA, IgG, and IgM) with quantitative assay (ELISA) analysis. Unpaired t-test, Welch test, or Mann–Whitney U test were applied for group comparisons when appropriate, and the correlation between variables was analyzed with Spearman’s rank coefficient. Results were considered significant at p < 0.05. Results. In the ADHD group, body weight (p ≤ 0.01), BMI (p ≤ 0.009), and hip circumference (p ≤ 0.001) significantly differed, while waist size and BMI z-score did not (p > 0.05). Significant elevation of the salivary sAA (p = 0.03), sIgA (p = 0.02), and IgM (p ≤ 0.001) biomarkers were detected, without differences in the morning cortisol (p > 0.05). Significant correlations between cortisol and BMI, hip size, and IgA, as well as between IgG and sAA and IgA were obtained. Conclusions. Saliva can be used to monitor ADHD status with regard to biomarkers indicating the hypothalamus–pituitary–adrenal axis, as HPA axis, and sympathetic activity. The results indicate that morning collection of saliva in contrast to unchanged salivary cortisol, may evaluate mentioned above system dysregulations by measurements of sAA and immunoglobulins among ADHD children.

The associations between ADHD, pain, inflammation, and quality of life in children and adolescents—a clinical study protocol

“…A recent study concluded that saliva can be used to monitor ADHD status with regard to biomarkers that indicate the hypothalamus-pituitary-adrenal axis and sympathetic activity [48]. Furthermore, as previously mentioned, ADHD is associated with a higher occurrence of autoimmune and inflammatory conditions [23].…”

Is There a Relationship Between ADHD and COVID-19 Prevalence and Mortality Indices? An Analysis of Data From 156 Countries

“…One possibility is that the immune and inflammatory changes associated with ADHD may be associated with a reduced likelihood of infection. These changes include lower levels of cortisol, elevated levels of interleukin-6 (IL-6) and C-reactive protein (CRP), and reduced levels of tumor necrosis factor alpha (TNF-α) in children and adolescents (Chang et al, 2020(Chang et al, , 2021Elsadek et al, 2020;Krahel et al, 2021), though these findings have not been consistent in adult patients (de Jong et al, 2016). The association with IL-6 is of particular interest, because genetic variants affecting the expression of IL-6 have been associated with variations in cross-national prevalence of COVID-19 (Karcioglu Batur & Hekim, Dongen et al, 2019), this hypothesis merits further investigation, as it may explain the finding of a possible "protective" effect (Arbel et al, 2020) despite the higher likelihood of "risky" behaviors in persons with ADHD.…”

“…This was confirmed in two recent reports which found that the presence of ADHD symptoms was associated with an increased likelihood of non-adherence to safety measures (Pollak et al, 2021a, 2021b). ADHD has also been associated with alterations in immune and inflammatory activity, such as elevated or decreased levels of particular inflammatory mediators (Anand et al, 2017; Chang et al, 2020, 2021; Krahel et al, 2021). It is not clear if these changes have a beneficial or harmful effect in individuals with SARS-CoV-2 infection (Yonas et al, 2020).…”

Inflammation, Anxiety, and Stress in Attention-Deficit/Hyperactivity Disorder

“…A single saliva or blood test at rest can evaluate baseline levels of peripheral markers of inflammation and/or the state of hormonal pathways that modulate immune and inflammatory systems [60,61], such as the sympathetic-adrenal-medullary (SAM) system and the hypothalamic-pituitary-adrenal (HPA) axis (for a review, see [62,63]). Peripheral markers of inflammation include, for example, anti-inflammatory (such as IL4, IL5, IL10, transforming growth factor-β [TGF-β], C-C motif chemokine ligand-14) and pro-inflammatory (IL1, IL2, IL6, IL8, IL12, TNF-α, interferon-gamma, monocyte chemoattractant protein-1 [MCP1]) chemokines and cytokines, their receptors (e.g., soluble TNF-receptor-1 [sTNF-R1]), acutephase proteins, blood immune cells, complement system components and antibodies.…”