Evaluation of peripheral inflammatory markers, serum B12, folate, ferritin levels and clinical correlations in children with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD)

Folic acid and autism: updated evidences

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that impairs communication, socialization, and behavior. The association of ASD with folic acid has been investigated due to the importance of this vitamin for neurological health. This study is an update of the publication 'Folic acid and autism: What do we know?' and aims to systematically review studies examining the relationship between folic acid and ASD. The search resulted in 2,389 studies on folic acid and ASD, which were selected by two reviewers based on their titles and abstracts. Studies meeting the inclusion criteria were fully read. The 52 included studies involved 10,429 individuals diagnosed with ASD and assessed the intake of vitamin B6, folic acid, and vitamin B12; serum levels of these vitamins, homocysteine, and methionine; therapeutic interventions using folic acid; and the association between maternal exposure to this vitamin and the risk of ASD. The evidence of insufficient folic acid intake in most individuals with ASD remains consistent in this update. No association was found between maternal exposure to folic acid and the risk of ASD in their children. Despite observed improvements in communication, socialization, and behavior in individuals with ASD following folic acid interventions, it is crucial to consider the individuality and complexity of ASD. Given the relevance of the topic, there remains a need for more high-quality research and clinical trials characterized by rigorous methodological designs.

Vitamins B9 and B12 in children with attention deficit hyperactivity disorder (ADHD)

Background: Attention deficit hyperactivity disorder (ADHD) is a common childhood neurodevelopmental disorder that begins before age 12. Given the role of B group vitamins in cell metabolism, synthesis of nucleotides, and neurotransmitters, the present study systematically investigated the plasma levels of vitamins B9 and B12 in children with ADHD. Methods: We searched electronic databases including Web of Science, MEDLINE, EMBASE, Scopus, Iran MEDEX, Cochran database, and SID from conception to June 2023. Full-text case-control or cross-sectional studies were included in this study. Participants in the case group were children with ADHD aged 6-12 years. Review Manager Software (RevMan 5.4) was used for statistical analyses. Standardized mean differences (SMD) with 95% CIs were used to determine the differences between the two groups. Results: Six studies were included in the present meta-analysis. They included 982 children, of whom, 204 were girls and 744 were boys. The mean age of the children was 8.86±2.03 years. The level of vitamin B9 was significantly different between children with and without ADHD [SMD -0.80, 95% CI (-1.55, -0.04)]. Vitamin B12 was significantly lower in children with ADHD [SMD -0.29, 95% CI (-0.42, -0.16)]. However, due to high heterogeneity (I2 = 93%), sensitivity analysis was used, I2 fell to 21%, and significant difference was observed between the two groups [SMD -0.19, 95% CI (-0.34, -0.04)]. Conclusion: The results of this systematic review showed that the level of vitamins B9 and B12 in children with ADHD was significantly lower than that in healthy children.

Vitamin B12 Supplementation in Psychiatric Practice

PURPOSE OF REVIEW

Vitamin B12 (B12, cobalamin) deficiency has been associated with neuropsychiatric symptoms, suggesting a role for B12 supplementation both as a treatment for psychiatric symptoms due to B12 deficiency and as an augmentation strategy for pharmacological treatments of psychiatric disorders. This critical review discusses the major causes of B12 deficiency, the range of psychiatric and non-psychiatric manifestations of B12 deficiency, the indications for testing B12 levels, and the evidence for B12 supplementation for major psychiatric disorders.

RECENT FINDINGS

We find that high-quality evidence shows no benefit to routine B12 supplementation for mild depressive symptoms or to prevent depression. There is very limited evidence on the role of B12 supplementation to augment antidepressants. No high-quality evidence to date suggests a role for routine B12 supplementation in any other major psychiatric disorder. No formal guidelines indicate when clinicians should test B12 levels for common psychiatric symptoms, in the absence of major risk factors for deficiency or cardinal symptoms of deficiency. No robust evidence currently supports routine B12 supplementation for major psychiatric disorders. However, psychiatrists should be aware of the important risk factors for B12 deficiency and should be able to identify symptoms of B12 deficiency, which requires prompt testing, medical workup, and treatment. Testing for B12 deficiency should be considered for atypical or severe psychiatric presentations.

Abnormal neutrophil-to-lymphocyte ratio in children with autism spectrum disorder and history of maternal immune activation

Maternal immune activation (MIA), related to autoimmune/inflammatory diseases or acute infections, during the two first trimesters of pregnancy is a risk factor for autism spectrum disorders (ASD) in offspring. In mice, MIA has a long-term impact on offspring's immune equilibrium resulting in a pro-inflammatory phenotype. We therefore hypothesized that children with ASD and a history of MIA could display a similar phenotype specifically assessed by a higher neutrophil to lymphocyte ratio (NLR). In this study, we used a retrospective sample of 231 dyads involving children with ASD and their mothers. Among ASD patients, 12% had a history of MIA. The multivariate analysis revealed a significant association between NLR in children with ASD and maternal history of MIA (F = 2.27, p = 0.03). Using a categorical approach, we observed an abnormal NLR (over 3) in 7.4% of children with ASD MIA+ compared to 1.9% for MIA-. Our study supports the hypothesis suggesting an impact of MIA on the risk of ASD. Further studies could contribute to the development of biomarkers in MIA+ ASD and enable the development of targeted immunomodulatory therapies.

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.

Pre- and post-treatment evaluation of routine blood analysis in patients with attention deficit hyperactivity disorder and comparison with the healthy control group

This study aimed to examine potential disparities in hematologic inflammation parameters between children diagnosed with attention deficit hyperactivity disorder (ADHD) and their healthy counterparts and to determine whether atomoxetine treatment induced any alterations in inflammation indicators. This case-control study involved 43 children aged 6-13 years, 22 diagnosed with ADHD for the first time, and 21 healthy children. In all children, complete blood count and albumin, C-reactive protein (CRP), thyroid stimulating hormone (TSH), free thyroxine (free T4), folate, vitamin B12, aspartate aminotransferase (AST), alanine transaminase (ALT), creatinine and urea values were performed. Children with ADHD were started on atomoxetine treatment, and one month later, the blood test was repeated for those who commenced treatment. Neutrophil (p = 0.005), platelet (PLT) (p = 0.002), neutrophil/lymphocyte ratio (NLR) (p = 0.001), platelet/lymphocyte ratio (PLR) (p < 0.001), systemic immune /inflammation index (SII) (p < 0.001) and pan-immune-inflammation value (PIV) (p = 0.025) parameters were found to be significantly higher than the control group, while the lymphocyte value (p = 0.001) was found to be significantly lower. In those in the ADHD group, lymphocyte (p = 0.041) and albumin (p = 0.027) values increased significantly after treatment. The results of this study show the increase in inflammation in drug-naive ADHD patients and the partial improvement after treatment. However, there is a need to evaluate inflammation in larger samples after longer-term treatments and follow-ups.

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.

Investigation of the relationship between vitamin D and peripheral inflammatory parameters in children with attention deficit and hyperactivity disorder

Aim: We aimed to investigate the effects of vitamin D and some nutritional factors such as vitamin B12, folate, homocysteine, and ferritin, which play a role in the pathogenesis of attention deficit and hyperactivity disorder (ADHD), on inflammation, which is also claimed to play a role in the pathogenesis of ADHD. Materials and methods: 39 ADHD and 39 healthy controls were compared with similar age, gender and BMI. The severity of the disease was evaluated with the Turgay ADHD scale. Inflammatory and nutritional parameters were measured routinely. Results: In the patient group, Vitamin D was found to be significantly lower (p

Activation of the Monocyte/Macrophage System and Abnormal Blood Levels of Lymphocyte Subpopulations in Individuals with Autism Spectrum Disorder: A Systematic Review and Meta-Analysis

Autism spectrum disorder (ASD) is a neurodevelopmental condition with a so far unknown etiology. Increasing evidence suggests that a state of systemic low-grade inflammation may be involved in the pathophysiology of this condition. However, studies investigating peripheral blood levels of immune cells, and/or of immune cell activation markers such as neopterin are lacking and have provided mixed findings. We performed a systematic review and meta-analysis of studies comparing total and differential white blood cell (WBC) counts, blood levels of lymphocyte subpopulations and of neopterin between individuals with ASD and typically developing (TD) controls (PROSPERO registration number: CRD CRD42019146472). Online searches covered publications from 1 January 1994 until 1 March 2022. Out of 1170 publication records identified, 25 studies were finally included. Random-effects meta-analyses were carried out, and sensitivity analyses were performed to control for potential moderators. Results: Individuals with ASD showed a significantly higher WBC count (k = 10, g = 0.29, p = 0.001, I2 = 34%), significantly higher levels of neutrophils (k = 6, g = 0.29, p = 0.005, I2 = 31%), monocytes (k = 11, g = 0.35, p < 0.001, I2 = 54%), NK cells (k = 7, g = 0.36, p = 0.037, I2 = 67%), Tc cells (k = 4, g = 0.73, p = 0.021, I2 = 82%), and a significantly lower Th/Tc cells ratio (k = 3, g = −0.42, p = 0.008, I2 = 0%), compared to TD controls. Subjects with ASD were also characterized by a significantly higher neutrophil-to-lymphocyte ratio (NLR) (k = 4, g = 0.69, p = 0.040, I2 = 90%), and significantly higher neopterin levels (k = 3, g = 1.16, p = 0.001, I2 = 97%) compared to TD controls. No significant differences were found with respect to the levels of lymphocytes, B cells, Th cells, Treg cells, and Th17 cells. Sensitivity analysis suggested that the findings for monocyte and neutrophil levels were robust, and independent of other factors, such as medication status, diagnostic criteria applied, and/or the difference in age or sex between subjects with ASD and TD controls. Taken together, our findings suggest the existence of a chronically (and systemically) activated inflammatory response system in, at least, a subgroup of individuals with ASD. This might have not only diagnostic, but also, therapeutic implications. However, larger longitudinal studies including more homogeneous samples and laboratory assessment methods and recording potential confounding factors such as body mass index, or the presence of comorbid psychiatric and/or medical conditions are urgently needed to confirm the findings.

Serum ferritin levels in children with attention deficit hyperactivity disorder and tic disorder

BACKGROUND

Iron plays an important role in neurodevelopmental functions in the brain. Serum ferritin levels are different in children with attention deficit hyperactivity disorder and tic disorder than in healthy children.

AIM

To explore the current status of iron deficiency in children with neurodevelopmental disorders and its sex and age effects.

METHODS

A total of 1565 children with attention deficit hyperactivity disorder (ADHD), 1694 children with tic disorder (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. The differences between the sexes in each disease were analyzed using the t test. The incidence rate of low serum ferritin was used to describe the differences between different diseases and different age groups. A chi-square test was used to analyze the difference in the incidence of low serum ferritin between the disease group and the control group. Analysis of variance was used for comparisons between subgroups, and regression analysis was used for confounding factor control.

RESULTS

A total of 1565 ADHD patients aged 5-12 years were included in this study, and the average serum ferritin levels of male and female children were 36.82 ± 20.64 μg/L and 35.64 ± 18.56 μg/L, respectively. A total of 1694 TD patients aged 5-12 years were included in this study, and the average serum ferritin levels of male and female children were 35.72 ± 20.15 μg/L and 34.54 ± 22.12 μg/L, respectively. 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%, among which male children with TD accounted for 9.25% and female children with TD accounted for 11.62%. There was a significant difference among the three groups (P < 0.05). In addition, there were 93 children with ASD with an average serum ferritin level of 30.99 ± 18.11 μg/L and a serum ferritin incidence of 15.05%.

CONCLUSION

In conclusion, low serum ferritin is not a risk factor for ADHD or TD. The incidence of low serum ferritin levels in children with ADHD and TD between 5 and 12 years old decreases first and then increases with age.

Peripheral Iron Levels in Autism Spectrum Disorders vs. Other Neurodevelopmental Disorders: Preliminary Data

Autism Spectrum Disorder (ASD) is characterized by deficits in social skills and specific behaviors and interests. Among other environmental factors, iron may play a role in the development of ASD. The aim of this study is to compare the iron status of children with ASD with that of children affected by neurodevelopmental disorders other than ASD (OND). A total of 167 patients were enrolled, including 93 children with ASD and 74 children with OND. In the two groups, we determined ferritin, iron, transferrin, hemoglobin, HCT, and MCV in the serum. We found a significant difference in serum ferritin and MCV levels between the two groups (p < 0.05), with lower ferritin and higher MCV values in the ASD group. There was no significant association with the other variables. Our results may support the hypothesis of altered iron status in ASD, justifying more frequent examinations of blood iron parameters in these children.

Could Candida Overgrowth Be Involved in the Pathophysiology of Autism?

The purpose of this review is to summarize the current acquiredknowledge of Candida overgrowth in the intestine as a possible etiology of autism spectrum disorder (ASD). The influence of Candida sp. on the immune system, brain, and behavior of children with ASD isdescribed. The benefits of interventions such as a carbohydrates-exclusion diet, probiotic supplementation, antifungal agents, fecal microbiota transplantation (FMT), and microbiota transfer therapy (MTT) will be also discussed. Our literature query showed that the results of most studies do not fully support the hypothesis that Candida overgrowth is correlated with gastrointestinal (GI) problems and contributes to autism behavioral symptoms occurrence. On the one hand, it was reported that the modulation of microbiota composition in the gut may decrease Candida overgrowth, help reduce GI problems and autism symptoms. On the other hand, studies on humans suggesting the beneficial effects of a sugar-free diet, probiotic supplementation, FMT and MTT treatment in ASD are limited and inconclusive. Due to the increasing prevalence of ASD, studies on the etiology of this disorder are extremely needed and valuable. However, to elucidate the possible involvement of Candida in the pathophysiology of ASD, more reliable and well-designed research is certainly required.