Evaluation of hematological inflammatory markers in children and adolescents with attention deficit/hyperactivity disorder

The Interplay Between Blood Inflammatory Markers, Symptom Domains, and Severity of ADHD Disorder in Children

OBJECTIVE

ADHD has a multi-factorial etiology among which the inflammatory theory presupposition. We aimed to explore the interplay between blood inflammatory markers; neutrophil lymphocyte ratios (NLR), platelet\lymphocyte ratio (PLR), mean platelet volume (MPV), symptom domains, and severity of ADHD.

METHOD

A total of 50 children with ADHD and 50 healthy controls were recruited. Children were assessed using the mini-international neuropsychiatric interview for children and adolescents (MINI-KID), the Wechsler intelligence scale for children, the Conners' parent rating scale. Then, NLR, PLR, and MPV were measured.

RESULTS

There was a statistically significant difference between children with ADHD and the control group with regard to all blood inflammatory markers (except platelet count). The subtypes and severity of ADHD had no significant relation with NLR, PLR, and MPV.

CONCLUSION

blood inflammatory markers are significantly high in children with ADHD but could not predict specific symptom domains or severity.

Neutrophil to lymphocyte ratio, platelet to lymphocyte ratio, and monocyte to lymphocyte ratio in ADHD: a systematic review and meta-analysis

Introduction

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder with an unclear etiology. Systemic inflammation and immune dysregulation may play a role in the pathogenesis of ADHD. Morphology-derived parameters such as neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and monocyte to lymphocyte ratio (MLR), have been proposed as peripheral biomarkers of the immune-inflammatory process in various diseases. However, studies examining their role in ADHD remain inconclusive.

Methods

A systematic review and a meta-analysis were conducted to evaluate the association between NLR, MLR, PLR and ADHD. Relevant articles were identified, screened, and assessed for quality according to PRISMA guidelines. Moreover, a qualitative and quantitative analyses were performed.

Results

The review contained eight eligible studies, five of which were included in the meta-analysis. The meta-analysis showed that ADHD patients had higher NLR and PLR values compared to health controls. No significant difference in MLR value was observed between the two groups. Analysis in relation to ADHD subtypes showed no significant differences in inflammatory markers in any of the included studies as well. The influence of medical treatment on these ratios could not be adequately assessed due to limited data.

Conclusion

ADHD patients exhibit higher NLR and PLR than healthy controls, which may indicate the potential immune-inflammatory involvement in this disorder. Further studies on inflammatory markers and ADHD, especially those considering the impact of treatment and clinical symptoms, are essential to comprehensively understand this association.

Peripheral Inflammatory Markers in Autism Spectrum Disorder and Attention Deficit/Hyperactivity Disorder at Adolescent Age

Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) are associated with immune dysregulation. We aimed to estimate the pro- and anti-inflammatory activity/balance in ASD and ADHD patients at a little-studied adolescent age with respect to sex. We evaluated 20 ASD patients (5 girls, average age: 12.4 ± 1.9 y), 20 ADHD patients (5 girls, average age: 13.4 ± 1.8 y), and 20 age- and gender-matched controls (average age: 13.2 ± 1.9 y). The evaluated parameters included (1) white blood cells (WBCs), neutrophils, monocytes, lymphocytes, platelets, platelet distribution width (PDW), mean platelet volume, and derived ratios, as well as (2) cytokines-interferon-gamma, interleukin (IL)-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, tumor necrosis factor-alpha (TNF-α), and derived profiles and ratios. ASD adolescents showed higher levels of WBC, monocytes, IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10, macrophages (M)1 profile, and anti-inflammatory profile than the controls, with ASD males showing higher monocytes, IL-6 and IL-10, anti-inflammatory profile, and a lower T-helper (Th)1/Th2+T-regulatory cell ratio than control males. The ADHD adolescents showed higher levels of PDW, IL-1β and IL-6, TNF-α, M1 profile, proinflammatory profile, and pro-/anti-inflammatory ratio than the controls, with ADHD females showing a higher TNF-α and pro-/anti-inflammatory ratio than the control females and ADHD males showing higher levels of IL-1β and IL-6, TNF-α, and M1 profile than the control males. Immune dysregulation appeared to be different for both neurodevelopmental disorders in adolescence.

Cardiovascular Disease Risk in Children and Adolescents with Attention Deficit/Hyperactivity Disorder

Objective

The aim of this case-controlled study is to evaluate chronic inflammation, subclinical atherosclerosis and cardiovascular disease risk in children and adolescents with ADHD.

Methods

A total of 51 medication-free children and adolescents with ADHD and 51 healthy controls were included in this study. K-SADS-PL was used to determine the diagnosis of ADHD and other psychiatric disorders. Conners' Parent Rating Scale-Revised Short Form and the Conners' Teacher Rating Scale-Revised Short Form severity of ADHD was used to evaluate severity of ADHD. In order to evaluate subclinical atherosclerosis, common carotid intima media thickness (IMT), epicardial adipose tissue thickness (EAT), and periaortic adipose tissue thickness (PAT) were assessed as well as clinical parameters.

Results

The IMT (0.037 ± 0.005 cm vs. 0.026 ± 0.003 cm), EAT (0.472 ± 0.076 cm vs. 0.355 ± 0.051 cm), and PAT (0.135 ± 0.016 cm vs. 0.118 ± 0.009 cm) measurements were significantly higher in the ADHD group than in the control group. Additionally, partial correlation analyses revealed that a positive correlation was observed between IMT and EAT, and PAT measurements separately. Multivariate linear regression analysis revealed that, body mass index (BMI) positively predicted IMT. Also, age and BMI positively predicted the EAT levels of the subjects with ADHD.

Conclusion

Our results suggest that children and adolescents with ADHD have a risk for cardiovascular disease. For this reason, subclinical atherosclerosis should be taken into consideration in the follow-up and treatment of ADHD for cardiovascular disease risk.