Twenty years of research on attention-deficit/hyperactivity disorder (ADHD): looking back, looking forward

Exploring the gut-brain Axis: Potential therapeutic impact of Psychobiotics on mental health

One of the most challenging and controversial issues in microbiome research is related to gut microbial metabolism and neuropsychological disorders. Psychobiotics affect human behavior and central nervous system processes via the gut-brain axis, involving neuronal, immune, and metabolic pathways. They have therapeutic potential in the treatment of several neurodegenerative and neurodevelopmental disorders such as depression, anxiety, autism, attention deficit hyperactivity disorder, Alzheimer's disease, Parkinson's disease, schizophrenia, Huntington's disease, anorexia nervosa, and multiple sclerosis. However, the mechanisms underlying the interaction between psychobiotics and the abovementioned diseases need further exploration. This review focuses on the relationship between gut microbiota and its impact on neurological and neurodegenerative disorders, examining the potential of psychobiotics as a preventive and therapeutic approach, summarising recent research on the gut-brain axis and the potential beneficial effects of psychobiotics, highlighting the need for further research and investigation in this area.

Attention-deficit/hyperactivity disorder in children with epilepsy: A systematic review and meta-analysis of prevalence and risk factors

OBJECTIVE

To evaluate the prevalence of and risk factors for attention-deficit/hyperactivity disorder (ADHD) in children with epilepsy (CWE).

METHODS

We conducted a systematic search in PubMed and Embase for the meta-analysis. The pooled prevalence of ADHD was calculated using a random-effects model; subgroup analyses were performed to explore heterogeneity. We collected raw data from articles reporting potential risk factors, which were included in the subsequent risk factor analysis.

RESULTS

Forty-six articles met the inclusion criteria for the meta-analysis, which showed a pooled ADHD prevalence of 30.7% in CWE, with a predominance of the inattentive subtype of ADHD; the heterogeneity of prevalence was related to population source/study setting (clinic based, community based, or database based) and method of ADHD diagnosis (with or without clinical review). Risk factors for ADHD in epilepsy included younger age, intellectual/developmental disabilities, a family history of epilepsy, earlier epilepsy onset, absence epilepsy, more frequent seizures, and polytherapy; In contrast, risk factors such as sex, generalized epilepsy or seizures, epilepsy etiology, and electroencephalogram abnormalities were not significantly associated with the occurrence of ADHD.

SIGNIFICANCE

The prevalence of ADHD in CWE is high and several potential risk factors are associated with it. This study contributes to a better understanding of ADHD in epilepsy for screening and treatment.

PLAIN LANGUAGE SUMMARY

This systematic review summarizes the prevalence of attention-deficit/hyperactivity disorder (ADHD) occurring in children with epilepsy and analyses the risk factors for comorbid ADHD in epilepsy. By reviewing 46 articles, we concluded that the overall prevalence of ADHD in children with epilepsy was 30.7% and that intellectual/developmental disabilities were the most significant risk factor for combined ADHD in children with epilepsy. This study provides a wealth of information on comorbid ADHD in epilepsy, which will help clinicians identify and treat potential ADHD in children with epilepsy in a timely manner.

The relation between MIND diet with odds of attention-deficit/hyperactivity disorder in Iranian children: a case-control study

This study aims to investigate the association between the MIND index (Mediterranean- Dietary approaches to Stop Hypertension diet Intervention for Neurodegenerative Delay) and attention-deficit hyperactivity disorder (ADHD) in the Iranian children. It builds upon existing research that highlights the role of dietary antioxidants in alleviating psychological disorders, cognitive impairments, and memory deficits. Additionally, previous studies have separately explored the beneficial effects of the Mediterranean and DASH diets on these issues. A case-control study was undertaken in Iran, involving a sample of 360 children and adolescents aged 7-13 years. Participants were divided into two groups, namely the case group (n = 120) and the control group (n = 240), with age and sex being matched between the groups. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV-TR) was employed for the diagnosis of ADHD. The MIND diet score was computed using the food intake data acquired from the Food Frequency Questionnaire (FFQ) completed by the subjects. The mean ± SD for the age and BMI of the study population was 8.76 ± 1.64 years and 16.90 ± 3.58 kg/m2, respectively. The mean score of MIND in this study was 27.93. After adjustment for potential confounder in the final model, subjects in highest compared to the lowest quartile of MIND diet score had significantly lower odds of ADHD (OR = 0.59, 95% CI 0.37-0.83; P-trend = 0.019). This study provides valuable evidence suggesting that adherence to the MIND diet is associated with decreased odds of ADHD.

Stimulant medications in children with ADHD normalize the structure of brain regions associated with attention and reward

Children with ADHD show abnormal brain function and structure. Neuroimaging studies found that stimulant medications may improve brain structural abnormalities in children with ADHD. However, prior studies on this topic were conducted with relatively small sample sizes and wide age ranges and showed inconsistent results. In this cross-sectional study, we employed latent class analysis and linear mixed-effects models to estimate the impact of stimulant medications using demographic, clinical measures, and brain structure in a large and diverse sample of children aged 9-11 from the Adolescent Brain and Cognitive Development Study. We studied 273 children with low ADHD symptoms and received stimulant medication (Stim Low-ADHD), 1002 children with high ADHD symptoms and received no medications (No-Med ADHD), and 5378 typically developing controls (TDC). After controlling for the covariates, compared to Stim Low-ADHD and TDC, No-Med ADHD showed lower cortical thickness in the right insula (INS, d = 0.340, PFDR = 0.003) and subcortical volume in the left nucleus accumbens (NAc, d = 0.371, PFDR = 0.003), indicating that high ADHD symptoms were associated with structural abnormalities in these brain regions. In addition, there was no difference in brain structural measures between Stim Low-ADHD and TDC children, suggesting that the stimulant effects improved both ADHD symptoms and ADHD-associated brain structural abnormalities. These findings together suggested that children with ADHD appear to have structural abnormalities in brain regions associated with saliency and reward processing, and treatment with stimulant medications not only improve the ADHD symptoms but also normalized these brain structural abnormalities.

Core items selection and psychometric properties of the adult attention-deficit hyperactivity disorder self-report scale-chinese short version (ASRS-CSV)

OBJECTIVE

This study aimed to develop and validate the Chinese Short Version of the Adult ADHD Self-Report Scale (ASRS-CSV), addressing the need for culturally appropriate diagnostic tools for Attention-Deficit Hyperactivity Disorder (ADHD) in the Chinese adult population.

METHODS

Utilizing a combination of intergroup difference analysis, factor analysis, and network analysis, we identified core ADHD symptoms pertinent to the Chinese cultural context. The study involved two samples: a vocational and technical school sample (N=1144) and an internet sample (N=1654), comprising adults aged 16-25 years. Reliability, validity, and diagnostic efficacy of the ASRS-CSV were assessed through psychometric testing.

RESULTS

The ASRS-CSV demonstrated high internal consistency (Cronbach's alpha > 0.9) and robust convergent validity (AVE > 0.7). The scale's diagnostic cutoff points were optimized, revealing high sensitivity and specificity for ADHD screening. Cross-cultural analysis highlighted differences in core ADHD symptoms between Chinese and Western populations, underscoring the scale's cultural sensitivity.

CONCLUSION

The ASRS-CSV is a reliable, valid, and efficient tool for screening ADHD in Chinese adults, reflecting the socio-cultural nuances of ADHD symptomatology. Its development marks a significant advancement in the field of psychiatry, offering a tailored approach for ADHD assessment in China and contributing to the global discourse on cross-cultural psychiatric diagnosis.

Paternal intelligence affects school grades in children with and without ADHD - a register-based study

ADHD profoundly impacts educational attainment, quality of life, and health in young adults. However, certain subgroups of ADHD patients seem to do quite well, potentially due to differences in intelligence and socioeconomic status. Here we used paternal intelligence from the Swedish Defence Conscription and Assessment register, to investigate the role of genetic propensity for intelligence, on school performance in a large cohort of ADHD patients and matched controls. Patients treated for ADHD in Linköping, Sweden between 1995 and 2020 (n = 3262), sex- and age-matched controls (n = 9591) as well as their parents and siblings were identified using regional and national registers. Socioeconomic and demographic data, ADHD diagnosis and treatment and school grades at age 16 for the study population were extracted from Swedish National registers. We explored the associations between paternal intelligence and child school performance using linear mixed models and mediation analyses, taking a wide range of potential covariates into account. Results indicate that paternal intelligence was positively associated with standardized school grades in their offspring (Zadjusted=0.09, 95%CI 0.07, 0.10). This effect was present in both ADHD patients and controls, but ADHD patients had significantly lower standardized grades (Zadjusted=-1.03, 95%CI -1.08, -0.98). Child ADHD did not serve as a mediator for how paternal intelligence affected school grades. Our findings indicate that ADHD prevents children from reaching their academic potential at all levels of paternal intelligence. Increased understanding of the contributions of ADHD, intelligence, and SES to functional outcomes can help clinicians to better personalize interventions to the unique preconditions in each patient.

The meaning of boredom : Properly managing childhood boredom could lead to more fulfilling lives

Boredom is a unique human emotion. Understanding its causes and consequences and how people learn to cope with it to develop new ideas and inspiration could help to alleviate its negative effects.

A critical review of the dextroamphetamine transdermal system for the treatment of ADHD in adults and pediatric patients

INTRODUCTION

The dextroamphetamine transdermal system (d-ATS) is a stimulant patch recently approved by the United States (U.S.) Food and Drug Administration for the treatment of attention-deficit/hyperactivity disorder (ADHD).

AREAS COVERED

The composition of the d-ATS, pharmacokinetics, and metabolism are presented along with data from dermal trials evaluating the tolerability of patch application at various skin sites. Efficacy and safety data from a laboratory classroom study in children and adolescents including effect sizes are assessed. Pharmacokinetic-pharmacodynamic modeling of variable wear times is also discussed.

EXPERT OPINION

Although stimulants are recommended as first-line treatment for ADHD in the U.S. some patients may have difficulty swallowing intact tablets and capsules, or dislike the taste or texture of chewable, oral disintegrating, or liquid formulations. The d-ATS fills an unmet need for those with ADHD who are unable or prefer not to take medication orally. Varying wear time of the d-ATS also gives flexibility in length of stimulant effect which may be useful for patients with changing schedules. However, dermal discomfort must be considered in addition to the usual amphetamine side effects when prescribing the d-ATS. Patient and provider experience will determine how frequent the use of d-ATS becomes.

Antihypertensive treatment during pregnancy induces long-term changes in gut microbiota and the behaviors of the attention deficit hyperactivity disorder offspring

The pathogenesis of attention-deficit/hyperactivity disorder (ADHD) has not been fully elucidated. Gestational hypertension could double the probability of ADHD in the offspring, while the initial bacterial communication between the mother and offspring has been associated with psychiatric disorders. Thus, we hypothesize that antihypertensive treatment during pregnancy may abate the impairments in neurodevelopment of the offspring. To test this hypothesis, we chose Captopril and Labetalol, to apply to pregnant spontaneously hypertensive rat (SHR) dams and examined the outcomes in the male offspring. Our data demonstrated that maternal treatment with Captopril and Labetalol had long-lasting changes in gut microbiota and behavioral alterations, including decreased hyperactivity and increased curiosity, spatial learning and memory in the male offspring. Increased diversity and composition were identified, and some ADHD related bacteria were found to have the same change in the gut microbiota of both the dam and offspring after the treatments. LC-MS/MS and immunohistochemistry assays suggested elevated expression of brain derived neurotrophic factor (BDNF) and dopamine in the prefrontal cortex and striatum of offspring exposed to Captopril/ Labetalol, which may account for the improvement of the offspring's psychiatric functions. Therefore, our results support the beneficial long-term effects of the intervention of gestational hypertension in the prevention of ADHD.

New Electrographic Marker? Evaluation of Sleep Spindles in Children with Attention Deficit Hyperactivity Disorder

Introduction: Attention deficit and hyperactivity disorder (ADHD) is one of the most common developmental disorders in childhood which lasts lifelong. Sleep structure and sleep spindle features are disorganized in ADHD. In this study, we aimed to look for a new, simple, inexpensive, and an easily detectable electrographic marker in the diagnosis of ADHD by using electroencephalography (EEG). Method: We included treatment free 35 patients with ADHD and 32 healthy children (HC) who were examined by polysomnography (PSG) and EEG for sleep disorders. The ADHD group were separated into three groups according to predominant presentations of ADHD. We determined the sleep staging and slow and fast sleep spindles, calculated each spindle's amplitude, frequency, activity, duration and density at non rapid eye movement (REM) sleep stage 2. Results: Slow sleep spindle's amplitude, duration, density and activity are significantly higher in ADHD group (most significant in ADHD-I) than the HC group (p < 0,05). Sleep spindle's features are not statistically significant between in ADHD subgroups. Conclusions: In children with ADHD, slow sleep spindles showed higher amplitude, activity, density and duration in the frontal regions. These results indicate that slow sleep spindles in children with ADHD may reflect executive dysfunction and slow frontal spindles may be useful as a new electrographic marker in children with ADHD. This is the first study of its kind evaluating all aspects of sleep spindles in ADHD patients.

The Effects of Theta/Beta-based Neurofeedback Training on Attention in Children with Attention Deficit Hyperactivity Disorder: A Systematic Review and Meta-analysis

Neurofeedback training is a common treatment option for attention deficit hyperactivity disorder (ADHD). Given theta/beta-based neurofeedback (T/B NF) training targets at the electrophysiological characteristics of children with ADHD, benefits for attention may be expected. PsycINFO, PubMed, ScienceDirect, Scopus, and Web of Science were searched through December 31, 2020. Studies were evaluated with Risk of Bias tools. Within-group effects based on Pre- and Post-treatment comparisons of the Intervention Group, and Between-group effects based on the between-group differences from Pre-treatment to Post-treatment were calculated. Nineteen studies met selection criteria for systematic review, 12 of them were included in meta-analysis. Within-group effects were medium at Post-treatment and large at Follow-up. Between-group analyses revealed that T/B NF was superior to waitlist control and physical activities, but not stimulant medication. Results showed that T/B NF has benefits for attention in children with ADHD, however, cautions should be taken when interpreting the findings.

Management Strategies for Borderline Personality Disorder and Bipolar Disorder Comorbidities in Adults with ADHD: A Narrative Review

This narrative review examines two of the common comorbidities of attention-deficit/hyperactivity disorder, bipolar disorder (BD), and borderline personality disorder (BPD), which each share several common features with ADHD that can make assessment and diagnosis challenging. The review highlights some of the key symptomatic differences between adult ADHD and these disorders, allowing for more careful consideration before establishing a formal diagnosis. When the disorders are found to be comorbid, further complications may arise; thus, the review will also help to provide evidence-based treatment recommendations as well as suggestions on how to minimize adverse events. Incorporating evidence from systematic reviews, journal articles, randomized controlled trials, and case reports, this review highlights that the diagnosis of ADHD and some of its common comorbidities is challenging and requires full, in-depth assessment and management. The management strategies of these comorbidities will also be addressed, with emphasis on achieving mood stabilization for BD prior to initiating appropriate ADHD pharmacotherapy. Medications, specifically mood stabilizers, antipsychotics, and antidepressants, are fundamental in treating symptoms seen in BD and some cases of BPD, alongside psychotherapy and lifestyle modifications when appropriate. The review highlights the effectiveness of specific medications, including psychostimulants, atomoxetine, and bupropion, as add-on therapies to mood-stabilizing treatments for addressing ADHD symptoms in patients with these comorbidities. Despite limited research, the review will address various pharmacological and psychotherapeutic approaches for managing comorbid ADHD and BPD, emphasizing the need for further investigations to better understand the unique needs of this patient population.

Mechanisms of cognitive disinhibition explain individual differences in adult attention deficit hyperactivity disorder traits

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) in adults is strongly associated with psychiatric comorbidity and functional impairment. Here, we aimed to use a newly developed online cognitive battery with strong psychometric properties for measuring individual differences in three cognitive mechanisms proposed to underlie ADHD traits in adults: 1) attentional control - the ability to mobilize cognitive resources to stop a prepotent motor response; 2) information sampling/gathering - adequate sampling of information in a stimulus detection task prior to making a decision; and 3) shifting - the ability to adapt behavior in response to positive and negative contingencies.

METHODS

This cross-sectional and correlational study recruited 650 adults (330 males) aged 18-69 years (M = 33.06; MD = 31.00; SD = 10.50), with previously diagnosed ADHD (n = 329) and those from the general community without a history of ADHD (n = 321). Self-report measures of ADHD traits (i.e., inattention/disorganization, impulsivity, hyperactivity) and the cognitive battery were completed online.

RESULTS

Latent class analysis, exploratory structural equation modeling and factor mixture modeling revealed self-reported ADHD traits formed a unidimensional and approximately normally distributed phenotype. Bayesian structural equation modeling demonstrated that all three mechanisms measured by the cognitive battery, explained unique, incremental variance in ADHD traits, with a total of 15.9% explained in the ADHD trait factor.

CONCLUSIONS

Attentional control and shifting, as well as the less researched cognitive process of information gathering, explain individual difference variance in self-reported ADHD traits with potential to yield genetic and neurobiological insights into adult ADHD.

Attention deficit hyperactivity disorder is associated with (a)symmetric tonic neck primitive reflexes: a systematic review and meta-analysis

Introduction

Investigation on the association between attention deficit hyperactivity disorder (ADHD) and primary reflexes is in the initial stage, with considerable differences in the findings. This study evaluated the association between ADHD and primitive reflexes using systematic review and meta-analysis.

Methods

Data were obtained from PubMed, Cochrane Library, Web of Science, EBSCO (Medical Literature Analysis and Retrieval System Online, American Psychological Association Psyclnfo, and Education Resources Information Center), Embase, Scopus, and ProQuest. Articles were searched from the date of inception of the respective databases to January 01, 2023, and StataCorp Stata (version 15) was used for the analysis.

Results

Four articles with 229 samples were included in the meta-analysis. Results showed a significant positive and moderate correlation between ADHD and primitive reflexes, particularly asymmetric tonic neck reflex: summary r value = 0.48, 95% CI = 0.27-0.64; symmetric tonic neck reflex: summary r value = 0.39, 95% CI = 0.25-0.52. Overall, findings from the sub-group analysis indicate that the behavioral problem measuring tool (Conners' scale), sex, and primitive reflex test could significantly moderate the relationships between ADHD and ATNR and STNR primitive reflexes.

Conclusion

ADHD symptoms in children are closely related to the non-integration of (a)symmetric tonic neck primitive reflexes. Longitudinal or experimental studies should be conducted to reveal the causal relationship between ADHD and primitive reflexes in the future.

Comparison of Fidgeting in Adolescents with Attention-Deficit/Hyperactivity Disorder Between Before and After Stimulant Medication Intake

Objective: Fidgeting is a common symptom in patients with attention-deficit hyperactivity disorder (ADHD). The current study investigated ADHD stimulant medication effects on fidgeting in adolescents with ADHD during a short research study session using wrist-worn accelerometers. Method: Adolescents with ADHD who had been taking stimulant medications (ADHD group) and adolescents without ADHD (control group) participated in the study. Accelerometer data were obtained from both wrists of each participant to track their hand movements during two hearing testing sessions. All subjects in the ADHD group abstained from their stimulant medications for at least 24 hours before their first session (off-med session). The second session (on-med session) was conducted about 60-90 minutes after medication intake. The control group participated in two sessions in a similar time frame. Results: The current study focuses on relationships between hand movements and stimulant medication in adolescents with ADHD. Both conditions were compared to evaluate the relationship of hand movements and stimulant medication. We hypothesized the ADHD group will exhibit less hand movements during the on-medication session in comparison to off-medication session. Conclusion: Wrist-worn accelerometer measures obtained during nonphysical tasks in a short duration may not provide hand movement differences between on-med and off-med conditions in adolescents with ADHD. ClinicalTrials.gov Identifier: NCT04577417.

Systematic bibliometric and visualized analysis of research hotspots and trends in attention-deficit hyperactivity disorder neuroimaging

Introduction

This study focused on the research hotspots and development trends of the neuroimaging of attention deficit hyperactivity disorder (ADHD) in the past thirty years.

Methods

The Web of Science database was searched for articles about ADHD neuroimaging from January 1992 to September 2022. CiteSpace was used to analyze the co-occurrence of keywords in literature, partnerships between authors, institutions, and countries, the sudden occurrence of keywords, clustering of keywords over time, and analysis of references, cited authors, and cited journals.

Results

2,621 articles were included. More and more articles have been published every year in the last years. These articles mainly come from 435 institutions and 65 countries/regions led by the United States. King's College London had the highest number of publications. The study identified 634 authors, among which Buitelaar, J. K. published the largest number of articles and Castellanos, F. X. was co-cited most often. The most productive and cited journal was Biological psychiatry. In recent years, burst keywords were resting-state fMRI, machine learning, functional connectivity, and networks. And a timeline chart of the cluster of keywords showed that “children” had the longest time span.

Conclusions

Increased attention has been paid to ADHD neuroimaging. This work might assist researchers to identify new insight on potential collaborators and cooperative institutions, hot topics, and research directions.

Perspectives of French adolescents with ADHD and child and adolescent psychiatrists regarding methylphenidate use

Many studies have demonstrated the short-term efficacy and tolerability of methylphenidate treatment adolescents with attention deficit hyperactivity disorder (ADHD). Qualitative literature on this matter focused on school outcomes, long-term side effects, family conflicts, personality changes and stigmatization. Yet, no qualitative study has crossed the perspectives of child and adolescent psychiatrists (CAPs) prescribing methylphenidate and adolescents with ADHD. This French qualitative study followed the five stages IPSE-Inductive Process to analyze the Structure of lived Experience-approach. Fifteen adolescents with ADHD and 11 CAPs were interviewed. Data collection by purposive sampling continued until data saturation was reached. Data analysis, based on a descriptive and structuring procedure to determine the structure of lived experience characterized by the central axes of experience, produced two axes: (1) The process of methylphenidate prescription, highlighting how this prescription was motivated from the exterior, experienced as passive by the adolescents and required commitment from the CAPs; and (2) the perceived effects of methylphenidate treatment, in three domains: at school, in relationships and in the sense of self. Findings raised both the issues of the epistemic position and social representation of the adolescents about ADHD and methylphenidate within this specific French context, and the self-awareness and perception of the adolescents with ADHD. We conclude that these two issues need to be regularly addressed by the CAPs prescribing methylphenidate to avoid epistemic injustice and prevent the harmful effects of stigmatization.

Autism and ADHD: A Literature Review Regarding Their Impacts on Parental Divorce

INTRODUCTION

The change in family structure as a consequence of divorce can be a traumatic event for a child that can undermine his or her emotional security. For this reason, it becomes a major health concern. Many divorce-related risk factors have been identified, including attention deficits or autism spectrum disorder (ASD) in children. The aim of this review is to evaluate if and how a diagnosis of ASD or attention deficit hyperactivity disorder (ADHD) in children is associated with an increase in divorce within families.

METHOD

Searches were performed in two databases evaluating studies focusing on articles pertaining to the topic. A total of 20 articles were found, but only 8 were included in the study according to the criteria.

RESULTS

The results showed that divorce does not appear to be specifically related to a diagnosed pathology of the child, but rather presents itself as a risk factor in certain situations. In particular, this occurs when the coping strategies required to deal with the diagnosis are dysfunctional. However, it would appear that families in which there are children with ADHD have a greater chance of divorce than families in which there is a child with a diagnosis of ASD. It may be hypothesised that in the latter case, parents receiving a diagnosis early in the child's life have more time to develop adaptive strategies to cope with the condition than parents with children with ADHD who mostly find themselves having to deal with their child's behavioural problems at a school age. Moreover, ASD is a disorder more likely genetic than environment-related, so parents receive more socio-medical support, and they are less likely to blame themselves or be blamed by others.

Time Perception in Adult ADHD: Findings from a Decade-A Review

Time perception is impaired in adult ADHD. Since the term time perception subsumes different constructs, including time estimation, time reproduction, time production, and duration discrimination, it remains open whether certain domains are more affected than other domains in adult ADHD. The aim of this explorative review is to present the current state of research on time perception in adult ADHD by analysing studies from the past 10 years. A review of the literature addressing adult ADHD time perception, time estimation, and time reproduction was performed. The search strategy was conducted by using the databases "PubMed", "Medline", and "PSYNDEX". The results of the present review indicate that the number of studies on time perception in adult ADHD is very scarce. Moreover, the main investigated domains of time perception in the past decade were time estimation, time reproduction and time management. Whereas some of the found studies were able to demonstrate a distinct deficit in time estimation, time reproduction and time management other studies were unable to demonstrate a clear association between ADHD and time estimation and time reproduction deficits. However, the diagnostic protocols, study design, and methodology varied between studies. Further studies on time estimation and time reproduction need to be carried out.

Effects of Physical Activity on Inhibitory Function in Children with Attention Deficit Hyperactivity Disorder: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to systematically evaluate the effect of physical activity (PA) on inhibitory function in children with ADHD. Experimental studies on the effect of PA on the inhibitory function of children with ADHD were retrieved. The data were obtained from PubMed, The Cochrane Library, Web of Science, EBSCO (MEDLINE, APA Psyclnfo, ERIC), Embase, Scopus, and ProQuest. The search period was from the date of inception of the respective databases to 4 May 2022, and Reviewer Manager software (version 5.3) was used for analysis. Eleven articles and 713 samples were included in the meta-analysis. Results revealed that PA can significantly improve the inhibitory function of children with ADHD (SMD = 0.78, 95% CI: 0.45−1.10, p < 0.001). Subgroup analysis showed that the effectiveness of PA as an intervention in improving the inhibitory function of children with ADHD was moderated by the frequency, intensity, duration, type, and length of intervention. Based on the findings, PA can effectively improve interference suppression inhibitory function in children with ADHD. Longitudinal open-skill exercise for 60 min or more, two times/week has the best effect on improving inhibitory function in children with ADHD.

Involvement of oxytocin receptor deficiency in psychiatric disorders and behavioral abnormalities

Oxytocin and its target receptor (oxytocin receptor, OXTR) exert important roles in the regulation of complex social behaviors and cognition. The oxytocin/OXTR system in the brain could activate and transduce several intracellular signaling pathways to affect neuronal functions or responses and then mediate physiological activities. The persistence and outcome of the oxytocin activity in the brain are closely linked to the regulation, state, and expression of OXTR. Increasing evidence has shown that genetic variations, epigenetic modification states, and the expression of OXTR have been implicated in psychiatric disorders characterized by social deficits, especially in autism. Among these variations and modifications, OXTR gene methylation and polymorphism have been found in many patients with psychiatric disorders and have been considered to be associated with those psychiatric disorders, behavioral abnormalities, and individual differences in response to social stimuli or others. Given the significance of these new findings, in this review, we focus on the progress of OXTR's functions, intrinsic mechanisms, and its correlations with psychiatric disorders or deficits in behaviors. We hope that this review can provide a deep insight into the study of OXTR-involved psychiatric disorders.

Right Superior Frontal Gyrus Cortical Thickness in Pediatric ADHD

OBJECTIVE

We investigated the right Superior Frontal Gyrus (right-SFG) and Anterior Cingulate Cortex (ACC) in children with ADHD and their clinical relevance with Executive Function (EF) and ADHD symptom severity.

METHODS

About 26 children with ADHD and 24 typically developing children (TDC; 7‒16 years) underwent Magnetic Resonance Imaging (MRI) and completed an EF assessment battery.

RESULTS

Significantly thinner right-SFG in the ADHD group was found compared to the TDC group (t (48) = 2.81, p = .007, Cohen's d = 0.84). Linear regression models showed that 12.5% of inattention, 13.6% of hyperactivity, and 9.0% of EF variance was accounted for by the right-SFG thickness.

CONCLUSIONS

Differences in the right-SFG thickness were found in our ADHD group and were associated with parent ratings of inattentive and hyperactive symptoms as well with EF ratings. These results replicate previous findings of thinner right-SFG and are consistent with the delayed cortical maturation theory of ADHD.

Exposure to Particulate Matter as a Potential Risk Factor for Attention-Deficit/Hyperactivity Disorder in Korean Children and Adolescents (KNHANES 2008-2018)

Many epidemiological studies have suggested that air pollution adversely affects neurodevelopment in children; however, evidence is still lacking. This study aimed to determine the association between particulate matter (PM) exposure and attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. Data were obtained from the Korean National Health and Nutrition Examination Survey 2008-2018. Outcomes were defined from parental reports of ever doctor-diagnosed ADHD, and ADHD cases were matched to non-cases with 1:10 age-sex matching. Individual exposure levels were assigned according to each study participant's administrative address during the year of diagnosis. Multivariate logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). After age-sex matching at a 1:10 ratio, the final study participants comprised 1,120 children aged 6-19 years old. A unit increase in the PM₁₀ concentration was significantly associated with ADHD (OR, 1.44; 95% CI, 1.02-2.02 per 10 µg/m³). The association with ADHD was stronger at higher quartiles than in the lower quartiles of PM₁₀ exposure; however, it was not statistically significant. Our results suggested that long-term PM₁₀ exposure was associated with increased ADHD in children and adolescents. Children diagnosed with ADHD suffer from a variety of social activity and have a significant economic burden. Therefore, it is considered an important role to find out the effects of environmental risk factors, including air pollution, on children and adolescents. This may also help to increase the body of knowledge in this field and to stimulate further research.

The Role of Mental Health and Behavioral Disorders in the Development of Temporomandibular Disorder: A SWEREG-TMD Nationwide Case-Control Study

Purpose

There is a well-known association between mental and behavioral disorders (MBD) and temporomandibular disorder (TMD), although the association has not been established in population-based samples. This study aimed to investigate this relationship using national population-based registry data.

Patients and Methods

This case-control study used prospectively collected data from Swedish national registries to investigate exposure to MBD and the probability of developing TMD in all Swedish citizens with hospital-diagnosed or surgically treated TMD between 1998 and 2016. Odds ratios were calculated using conditional logistic regression adjusted for educational level, living area, country of birth, musculoskeletal comorbidity, and history of orofacial/neck trauma.

Results

A statistically significant association between MBD and TMD was found for mood affective disorders (OR 1.4), neurotic, stress-related and somatoform disorders (OR 1.7), behavioral syndromes associated with psychological disturbances and physical factors (OR 1.4), disorders of adult personality and behavior (OR 1.4), disorders of psychological development (OR 1.3), behavioral and emotional disorders with onset usually occurring in childhood and adolescence (OR 1.4), and unspecified mental disorder (OR 1.3). The association was stronger for TMD requiring surgery, with the strongest association in patients with disorders of psychological development (OR 2.9). No significant association was found with schizophrenia, schizotypal and delusional disorders, or mental retardation.

Conclusion

The findings indicate an increased probability of TMD among patients with a history of certain MBD diagnoses, and a stronger association with TMD requiring surgery, specifically repeated surgery. This highlights the need for improved preoperative understanding of the impact of MBD on TMD, as TMD and chronic pain itself may have a negative impact on mental health.

Sleep electroencephalogram evidence of delayed brain maturation in attention deficit hyperactivity disorder: a longitudinal study

Study Objectives

This study investigates whether longitudinally measured changes in adolescent brain electrophysiology corroborate the maturational lag associated with attention deficit hyperactivity disorder (ADHD) reported in magnetic resonance imaging (MRI) studies and cross-sectional sleep electroencephalogram (EEG) data.

Methods

Semiannually nine adolescents diagnosed with ADHD (combined presentation, DSM-V criteria, mean age 12.39 ± 0.61 years at first time-point, two females) and nine typically developing controls (12.08 ± 0.35 years, four females) underwent all-night laboratory polysomnography, yielding four recordings.

Results

Sleep macrostructure was similar between groups. A quadratic model of the age change in non-rapid eye movement (NREM) delta (1.07–4 Hz) power, with sex effects accounted for, found that delta power peaked 0.92 ± 0.37 years later in the ADHD group. A Gompertz function fit to the same data showed that the age of most rapid delta power decline occurred 0.93 ± 0.41 years later in the ADHD group (p = 0.037), but this group difference was not significant (p = 0.38) with sex effects accounted for. For very low frequency (0.29–1.07 Hz) EEG, the ADHD lag (1.07 ± 0.42 years later, p = 0.019) was significant for a Gompertz model with sex effects accounted for (p = 0.044). Theta (4–7.91 Hz) showed a trend (p = 0.064) toward higher power in the ADHD group. Analysis of the EEG decline across the night found that standardized delta and theta power in NREMP1 were significantly (p &lt; 0.05 for both) lower in adolescents with ADHD.

Conclusions

This is the first longitudinal study to reveal electrophysiological evidence of a maturational lag associated with ADHD. In addition, our findings revealed basically unaltered sleep macrostructure but altered sleep homeostasis associated with ADHD.

Viloxazine, a Non-stimulant Norepinephrine Reuptake Inhibitor, for the Treatment of Attention Deficit Hyperactivity Disorder: A 3 Year Update

Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental disorder in childhood. Current treatment options for ADHD include pharmacological treatment (stimulants, non-stimulants, anti-depressants, anti-psychotics), psychological treatment (behavioral therapy with or without parent training, cognitive training, neurofeedback), and complementary and alternative therapies (vitamin supplementation, exercise). Central nervous system (CNS) stimulants are the primary pharmacological therapy used in treatment; however, these stimulant drugs carry a high potential for abuse and severe psychological/physical dependence. Viloxazine, a non-stimulant medication without evidence of drug dependence, is a selective norepinephrine reuptake inhibitor that has historically been prescribed as an anti-depressant medication. The extended-release (ER) form was approved by the US Food and Drug Administration (FDA) in April 2021 for the treatment of ADHD in pediatric patients aged 6-17 years. Phase 2 and 3 randomized control trials have demonstrated significant efficacy of viloxazine in improving ADHD symptoms versus placebo. Related to its long-standing use as an antidepressant, the safety profile and pharmacokinetics of viloxazine are well understood. Viloxazine appears to be a suitable alternative to current standard-of-care pharmacotherapy for ADHD, but the further investigation remains to be done in comparing its efficacy to that of current treatments.

Developmental Risk, Adversity Experiences and ADHD Clinical Profiles: A Naturalistic Exploratory Study

Attention-deficit/hyperactivity disorder (ADHD) is a persistent neurodevelopmental disorder that results from complex interactions of multiple genes and environmental risk and adversity factors. Some researchers have suggested a need for additional research into differing clinical presentations of ADHD for further classification. In this context, this study aimed to investigate whether increases in risk and adversity factors increase the severity of ADHD and the number of comorbid psychiatric disorders. This is a naturalistic retrospective chart review exploratory study in 100 patients 16 years or older who have a confirmed diagnosis of ADHD. The quantitative data were analyzed using SPSS, using the Mann–Whitney test for parametric data and the Chi-square and Kruskal–Wallis p value tests for non-parametric and categorical data. Qualitative data were tabulated and described. The study found that (1) the average number of comorbidities increases with the severity of ADHD, (2) the average number of risk and adversity factors increases with the severity of ADHD, (3) the number of risk and adversity factors were positively associated with the number of comorbidities, and (4) Level of education was negatively associated with the number of risk and adversity factors and the number of comorbidities. The implications of these findings are discussed, and future research in this important area is suggested.

Listening to White Noise Improved Verbal Working Memory in Children with Attention-Deficit/Hyperactivity Disorder: A Pilot Study

Existing research demonstrates that children with attention-deficit/hyperactivity disorder (ADHD) underperform in cognitive tasks involving working memory (WM) due to hypo-arousal, which has led to the development of arousal regulation models to determine proper levels of arousal and optimal cognitive outcomes. The present study focuses on investigating the effects of external auditory stimuli on verbal WM in children with ADHD. Thirteen children with ADHD (aged 6–10 years old) and thirteen age- and gender-matched children with typical development (TD) completed the verbal WM task when listening to no sound, white noise, or pleasant music. A two-way repeated-measures analysis of variance was used to compare the verbal WM performance between groups in the three auditory conditions. Children with ADHD showed the best verbal WM performance when listening to white noise and the worst performance when listening to no sound. Yet, children with TD performed the best in the no-sound condition and the worst in the white noise condition. Our findings suggest auditory white noise is beneficial for ideal arousal regulation and cognitive performance involving verbal WM for children with ADHD and support the moderate brain arousal model. Providing external white noise is a non-invasive and cost-effective approach to improving verbal WM in children with ADHD in real-world contexts.

Occupational Branch and Labor Market Marginalization among Young Employees with Adult Onset of Attention Deficit Hyperactivity Disorder-A Population-Based Matched Cohort Study

We compared labor market marginalization (LMM), conceptualized as days of unemployment, sickness absence and disability pension, across occupational branches (manufacturing, construction, trade, finance, health and social care, and education), among young employees with or without attention deficit hyperactivity disorder (ADHD) and examined whether sociodemographic and health-related factors explain these associations. All Swedish residents aged 19–29 years and employed between 1 January 2005 and 31 December 2011 were eligible. Individuals with a first ADHD diagnosis (n = 6030) were matched with ten controls and followed for five years. Zero-inflated negative binomial regression was used to model days of LMM with adjustments for sociodemographic and health-related factors. In total, 20% of those with ADHD and 59% of those without had no days of LMM during the follow-up. The median of those with LMM days with and without ADHD was 312 and 98 days. Having an ADHD diagnosis was associated with a higher incidence of LMM days (incident rate ratios (IRRs) 2.7–3.1) with no differences across occupational branches. Adjustments for sociodemographic and health-related factors explained most of the differences (IRRs: 1.4–1.7). In conclusion, young, employed adults with ADHD had a higher incidence of LMM days than those without, but there were no substantial differences between branches, even after adjusting for sociodemographic and health-related factors.

Wishes of Children With ADHD

Understanding the desires and motivations of children with ADHD is important in helping them thrive. Their inner worlds, however, have not been well captured. The Three Wishes task provides minimal cues and structure to elicit their desires and hopes in an unbiased manner. The wishes of 299 school-aged children with ADHD (193 boys, aged 6-12) were elicited during a research diagnostic assessment. We developed a coding scheme to characterize different aspects of their wishes, including beneficiary, valence, and immediacy. Maslow's hierarchy of needs, adapted to take account of the participants' ages, was used to identify the motivations underlying the children's wishes. As expected, many of the wishes reported were for immediate fulfillment, with many reflecting material desires. Affiliative wishes, highlighting the children's desire for positive interpersonal relationships, were also common. There was some evidence for self-actualization/self-betterment goals and a small number of altruistic wishes. A word cloud presents the content of the children's wishes grouped according to this hierarchy. This study highlights the diversity and typicality of the self-reported needs, desires and hopes of children with ADHD. It also serves as a timely reminder of the value of seeking such information directly from children themselves.

Prenatal risk factors and genetic causes of ADHD in children

BACKGROUND

Attention deficit/hyperactivity disorder (ADHD) is a common disease among children; it affected 5-7% of the population in 2015. ADHD is a multifactorial disease, and its etiology is still not clearly understood.

DATA SOURCES

This narrative review has been done by searching the PubMed and Embase databases using attention deficit/hyperactivity disorder, ADHD, risk factors; genetics; pediatrics; psychiatrics as keywords.

RESULTS

ADHD is considered to be a hereditary disorder in which genes play the fundamental role in the pathogenesis; however, findings from genetic-environmental studies support the hypothesis that genetic factors can exert effects on an individual's condition by determining his/her responses to environmental exposures, especially those during the prenatal stage.

CONCLUSION

ADHD is considered as a hereditary disorder in which genes and prenatal risk factors play fundamental roles in the pathogenesis.

Clinical characteristics, neuroimaging findings, and neuropsychological functioning in attention-deficit hyperactivity disorder: Sex differences

Recent clinical studies, in both children/adolescents and adults, have shown the extreme neuropsychological heterogeneity of attention-deficit hyperactivity disorder (ADHD): specific neuropsychological deficits have been found only in a minority of individuals, with no direct correlation between discrete cognitive performances and the trajectory of clinical symptoms. Deficits in specific neuropsychological functions may be common in ADHD, but nevertheless no cognitive or neuropsychological profile may fully explain the disorder. Sex differences in the ADHD presentation, both at a neuropsychological and clinical level, also contribute to this clinical and neuropsychological heterogeneity. At a neuropsychological level, females with ADHD may show greater working memory problems, poorer vocabulary skills and worse visual spatial reasoning. Structural and functional imaging study also show discrete differences across sex; however, the great majority of clinical studies mainly or exclusively include male participants with insufficient data to draw firm conclusions on sex differences within the disorder. Here, we report the recent literature data, discussing still open research questions about the clinical presentation, neuroimaging findings, and neuropsychological functioning in ADHD with a focus on the impact of sex differences-a deeper insight in these unresolved issues may have relevant clinical and therapeutic implications for tailored, effective, and long-lasting interventions.

Risk Factors for Disability Pension among Young Adults Diagnosed with Attention-deficit Hyperactivity Disorder (ADHD) in Adulthood

OBJECTIVE

To investigate risk factors of disability pension (DP) in young adults diagnosed with ADHD in Sweden.

METHOD

In total, 9718 individuals diagnosed with incident ADHD in young adult age (19-29 years) 2006 to 2011, were identified through national registers. They were followed for 5 years and Cox regression models were applied to analyze the DP risk (overall and by sex), associated with socio-demographics, work-related factors, and comorbid disorders.

RESULTS

Twenty-one percent of all received DP. Being younger at diagnosis (hazard ratio [HR] = 1.54; 95%confidence interval [CI] 1.39-1.71); low educational level (HR = 1.97; 95%CI 1.60-2.43 for <10 years); work-related factors at baseline (no income from work [HR = 2.64; 95%CI 2.35-2.98] and sickness absence >90 days [HR = 2.48; 95%CI2.17-2.83]); and schizophrenia/psychoses (HR = 2.16; 95%CI 1.66-2.80), autism (HR = 1.87; 95%CI 1.42-2.46), anxiety (HR = 1.34; 95%CI 1.22-1.49) were significantly associated with an increased risk of DP. Similar risk patterns were found in men and women.

CONCLUSION

Work-related factors and comorbid mental disorders need to be highlighted in early vocational rehabilitation for individuals with ADHD.

Maternal infection during pregnancy and the risk of attention-deficit/hyperactivity disorder in the offspring: A systematic review and meta-analysis

BACKGROUND

The effects of maternal infection during pregnancy on the risk of attention-deficit/hyperactivity disorder (ADHD) in the offspring are unclear, and no overview is available.

METHODS

We searched the PubMed and EMBASE databases for relevant studies and performed a systematic review and meta-analysis of the literature.

RESULTS

We found that that maternal infection during pregnancy was associated with a small increase in the risk of ADHD (OR 1.25, 95% CI 1.09, 1.44, P < 0.0001; I² = 92.9%, p < 0.0001) in the offspring. In subgroup analyses, the association remained for maternal genitourinary (GU) infection (OR, 1.19, 1.12, 1.27, P < 0.001; I² = 0%; p = 0.517). However, there was no significant association when we pooled data from siblings from other pregnancies (OR = 1.06, 95% CI, 0.99-1.13, P = 0.084; I² = 0%; p = 0.859), implying that the association was due to confounding.

CONCLUSIONS

The statistically significant association between maternal infection during pregnancy and ADHD in the offspring can be partially explained by unmeasured confounding.

The Association between ADHD and the Severity of COVID-19 Infection

OBJECTIVE

Patients with ADHD are at increased risk of acquiring COVID-19. The present study assessed the possibility that ADHD also increases the risk of severe COVID-19 infection.

METHOD

We assessed 1,870 COVID-19 positive patients, aged 5 to 60 years, registered in the database of Leumit Health Services (LHS, Israel), February to -June 2020, of whom 231 with ADHD. Logistic regression analysis models evaluated the association between ADHD and the dependent variables of being symptomatic/referral to hospitalization, controlling for demographic and medical variables.

RESULTS

Age, male sex, and BMI were confirmed to be significant risk factors for increased COVID-19 severity. ADHD was found to be associated with increased severity of COVID-19 symptoms (OR = 1.81, 95% CI [1.29, 2.52], p < .05) and referral to hospitalization (OR =1.93, 95% CI [1.06, 3.51], p = .03).

CONCLUSION

ADHD is associated with poorer outcomes in COVID-19 infection.

Individuals at Risk of Exercise Addiction Have Higher Scores for Depression, ADHD, and Childhood Trauma

Background

Exercise addiction is increasingly being recognized as a psychologically and physically burdensome set of symptoms. However, little is known about the psychiatric profiles of individuals who are at risk. It is well-established that individuals affected by substance use disorders frequently suffer from depression, attention deficit hyperactivity disorder (ADHD), and experiences of childhood trauma. The aim of this study is to determine whether this pattern of psychiatric disturbance is also present in individuals at risk for exercise addiction.

Methods

Individuals exercising for 10+ h/week were divided into those at risk and not at risk for exercise addiction based on their scores on the Exercise Dependence Scale (EDS). Demographic data and scores on the Beck Depression Inventory (BDI), a measure for ADHD in adults and the Childhood Trauma Questionnaire (CTQ) were also gathered.

Results

One hundred and twenty-three individuals agreed to participate in the study, and completed the questionnaires. Twenty-nine (23.6%) of these individuals were classed as at risk for exercise addiction. There was a statistically significant difference between the at-risk and not at-risk groups on the combined dependent variable after controlling for hours of exercise per week, F_{(3, 95)}= 10.198, p = 0.00, Wilk's Λ = 0.756, partial η2 = 0.244. Compared to those not at risk, individuals at risk for exercise addiction had significantly higher scores for symptoms of depression [t₍₁₂₁₎ = 4.944, p = 0.000], ADHD [t₍₁₂₁₎ = 2.915, p = 0.004], and childhood trauma [t₍₁₂₁₎ = 2.297, p = 0.024].

Conclusion

Our results suggest that exercise addiction may be accompanied by a disturbed psychiatric profile consistent with other addictive disorders. Clinical interviewing in individuals at risk for exercise addiction is a valuable and worthwhile next step in characterizing this phenomenon.

Chlorpyrifos residue level and ADHD among children aged 1-6 years in rural China: A cross-sectional study

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood and is caused by both genetic and environmental factors. As genetic factors are nonmodifiable, environmental factors have attracted increasing attention.

OBJECTIVE

To investigate the relationships between urinary chlorpyrifos (CPF) levels, blood micronutrient levels, and ADHD prevalence in children living in rural areas of China.

METHODS

This cross-sectional study collected data on CPF exposure (according to urinary levels), blood micronutrient levels, and ADHD prevalence in children aged 1-6 years in rural China. The CPF levels were determined by mass spectrometry. Blood levels of micronutrients, including zinc, iron, calcium, copper, magnesium, and vitamin D, were measured by professional detection kits. ADHD was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Descriptive statistics and univariate analysis were conducted using SPSS 21.0, and path analysis was conducted using Mplus 8.0.

RESULTS

Of the 738 children who met the eligibility criteria, 673 children (673/738, 91.2%) were included in the final analysis. Baseline questionnaires and urine samples were collected from all 673 subjects. A total of 672 children provided blood samples for micronutrient testing, and 651 completed the ADHD assessment. Approximately one-fifth of children (144/673, 21.4%) had detectable levels of CPF in their urine, and 6.9% (45/651) were diagnosed with ADHD. Path analysis showed that the total effect of CPF exposure on ADHD risk was 0.166 (P < 0.05), with a direct effect of 0.197 (P < 0.05) and an indirect effect of -0.031 (P < 0.05) via vitamin D. The mediating effect of urinary CPF levels on ADHD risk via vitamin D was 18.67%.

CONCLUSION

Higher levels of CPF exposure are associated with higher risk of ADHD. Additionally, increasing vitamin D levels may have a beneficial effect on the relationship between CPF exposure and ADHD risk. Our findings highlight the importance of modifying environmental factors to reduce ADHD risk and provide insight into future ADHD interventions.

Association Between Exposure to Pesticides and ADHD or Autism Spectrum Disorder: A Systematic Review of the Literature

OBJECTIVE

To conduct a systematic review of studies assessing the relationship between exposure to pesticides and ADHD or Autism Spectrum Disorder (ASD).

METHODS

Based on a pre-registered protocol in PROPSERO (CRD42018107847), we searched PubMed, Ovid databases, and ISI Web of Knowledge with no date/language/document type restrictions, up to May 2019. The Newcastle Ottawa Scale was used to assess study quality.

RESULTS

Among the 29 retained studies, 13 focused on ADHD, 14 on ASD, and two on both disorders. Ten studies reported a significant association between exposure to pesticides and ADHD/ADHD symptoms and 12 studies found a significant association with ASD/ASD traits. The strengths of the association and the possible confounders controlled for varied substantially across studies.

CONCLUSION

Whilst there is some evidence suggesting a possible link between pesticides and ADHD/ASD, heterogeneity across studies prevents firm conclusions. We provide methodological indications for future studies.

Attention Deficit Hyperactivity Disorder and Bipolar Disorder: Diagnosis, Treatments, and Clinical Considerations: A Narrative Review

Attention-deficit Hyperactivity Disorder is one of the most common childhood mental health disorders, affecting about 5.6% of the population worldwide. Several studies have specifically shown a high prevalence of comorbid mood disorders, such as depression and bipolar disorder (BD), in those diagnosed with ADHD. Several common symptoms of ADHD are also found in BD, which are characterized by alternating periods of euthymia and mood disturbances. The inattention and impulsivity of ADHD can be seen in manic and hypomanic episodes of BD. Over the past decade, there has been an increased interest in research between the correlation of ADHD and pediatric bipolar disorder (PBD) in children. Some experts hypothesize that more children are comorbidly diagnosed with ADHD and PBD because of how many clinicians treat children with ADHD. Other factors, which may affect the dual diagnoses of ADHD and PBD, are overlapping diagnostic criteria for the two disorders, the inevitable biases seen when one disorder is diagnosed without the other, and related risk factors leading to prodromal relationships. By examining clinical trials, a better understanding of whether ADHD and PBD have a stepwise progression or if other factors influence these comorbidities, such as blurred lines of diagnostic criteria. Those with ADHD are also at an increased risk of impairment at work and in social settings. This manuscript explores both progression of this disease and its clinical connections to other disorders.

Probiotics: Potential novel therapeutics for microbiota-gut-brain axis dysfunction across gender and lifespan

Probiotics are live microorganisms, which when administered in adequate amounts, present a health benefit for the host. While the beneficial effects of probiotics on gastrointestinal function are generally well recognized, new animal research and clinical studies have found that alterations in gut microbial communities can have a broad range of effects throughout the body. Non-intestinal sites impacted include the immune, endocrine, cardiovascular and the central nervous system (CNS). In particular, there has been a growing interest and appreciation about the role that gut microbiota may play in affecting CNS-related function through the 'microbiota-gut-brain axis'. Emerging evidence suggests potential therapeutic benefits of probiotics in several CNS conditions, such as anxiety, depression, autism spectrum disorders and Parkinson's disease. There may also be some gender-specific variances in terms of probiotic mediated effects, with the gut microbiota shaping and being concurrently molded by the hormonal environment governing differences between the sexes. Probiotics may influence the ability of the gut microbiome to affect a variety of biological processes in the host, including neurotransmitter activity, vagal neurotransmission, generation of neuroactive metabolites and inflammatory response mediators. Some of these may engage in cross talk with host sex hormones, such as estrogens, which could be of relevance in relation to their effects on stress response and cognitive health. This raises the possibility of gender-specific variation with regards to the biological action of probiotics, including that on the endocrine and central nervous systems. In this review we aim to describe the current understanding in relation to the role and use of probiotics in microbiota-gut-brain axis-related dysfunction. Furthermore, we will address the conceptualization and classification of probiotics in the context of gender and lifespan as well as how restoring gut microbiota composition by clinical or dietary intervention can help in supporting health outcomes other than those related to the gastrointestinal tract. We also evaluate how these new learnings may impact industrial effort in probiotic research and the discovery and development of novel and more personalized, condition-specific, beneficial probiotic therapeutic agents.

Associations between dimensions of behaviour, personality traits, and mental-health during the COVID-19 pandemic in the United Kingdom

The COVID-19 pandemic (including lockdown) is likely to have had profound but diverse implications for mental health and well-being, yet little is known about individual experiences of the pandemic (positive and negative) and how this relates to mental health and well-being, as well as other important contextual variables. Here, we analyse data sampled in a large-scale manner from 379,875 people in the United Kingdom (UK) during 2020 to identify population variables associated with mood and mental health during the COVID-19 pandemic, and to investigate self-perceived pandemic impact in relation to those variables. We report that while there are relatively small population-level differences in mood assessment scores pre- to peak-UK lockdown, the size of the differences is larger for people from specific groups, e.g. older adults and people with lower incomes. Multiple dimensions underlie peoples’ perceptions, both positive and negative, of the pandemic’s impact on daily life. These dimensions explain variance in mental health and can be statistically predicted from age, demographics, home and work circumstances, pre-existing conditions, maladaptive technology use and personality traits (e.g., compulsivity). We conclude that a holistic view, incorporating the broad range of relevant population factors, can better characterise people whose mental health is most at risk during the COVID-19 pandemic.

The COVID-19 pandemic has affected people’s health and well-being. Here, the authors characterize self-reported impact of the pandemic (positive and negative) at a large scale in the United Kingdom, and show variance among individual circumstances.

Risk of Respiratory Infectious Diseases and the Role of Methylphenidate in Children with Attention-Deficit/Hyperactivity Disorder: A Population-Based Cohort Study

Children with attention-deficit/hyperactivity disorder (ADHD) are commonly affected by medical illness. The aim of the present study was to explore the risks of contracting respiratory infectious diseases (RIDs), including upper and lower RIDs and influenza, in children with ADHD. We also examined whether methylphenidate has a protective effect regarding the risk of contracting RIDs among children with ADHD who have a history of methylphenidate treatment. Children in the Taiwan Maternal and Child Health Database from 2004 to 2016 were included in the present study. Upper and lower RIDs, influenza, ADHD, age, sex, and records of methylphenidate prescription were identified. A Cox proportional hazards regression model was used to estimate the significance of the risk of RIDs among children with ADHD in comparison with that among children without ADHD after adjustment for sex and age. The self-controlled case series analysis was conducted to examine the protective effect of methylphenidate treatment against RIDs. In total, 85,853 children with ADHD and 1,458,750 children without ADHD were included in the study. After controlling for sociodemographic variables, we observed that children with ADHD had significantly higher risks of upper RIDs, lower RIDs, and influenza infection than did those without ADHD. Among the children with ADHD who had a history of methylphenidate treatment, the risk of contracting RIDs was lower during the methylphenidate treatment period than during the nontreatment period. Children with ADHD had a higher RID risk than those without ADHD. Methylphenidate might reduce the risk of RIDs among children with ADHD who have a history of methylphenidate treatment.

SKILLS - A psychoeducational group programme for children with ADHD

Psychoeducation is regarded as a first line of intervention for attention-deficit/hyperactivity disorder (ADHD). Previous studies have been limited to psychoeducation for adult patients or parents of children with ADHD. Therefore, the aim of the present study was to investigate the acceptability and effectiveness of a psychoeducational group intervention for children with ADHD. The two-session psychoeducational intervention, SKILLS, was completed by 125 children (6-12 years) with ADHD and their parents. Self-ratings and parental ratings of ADHD symptoms, functional impairment and attitudes to diagnosis and treatment were collected before and after treatment. Post-treatment client satisfaction and parental responses to an open question about SKILLS were assessed. The data were analyzed using a combination of quantitative and qualitative (content analysis) methods. A majority of the participants expressed satisfaction with the group intervention. The intervention had no effect on symptoms and level of function, although the parents were more positive to their child's diagnosis after the intervention. The parents were positive to the group format and to the opportunity for their children to meet other children with similar symptoms. Parents wished for more interactive elements and more opportunities for children to share experiences. We concluded that the group intervention was accepted by most participants, although more activating exercises and opportunities for interaction between participants should be included. Since the intervention group was not compared with a control group, the results should be interpreted with caution. Future studies should use a randomized control treatment design and investigate the effect on adherence to later treatment.

Effectiveness and safety of dexamphetamine sulfate (Attentin®) in the routine treatment of children and adolescents with ADHD: results from a 12-month non-interventional study

Background

Randomized controlled trials have shown that dexamphetamine sulfate (DEX) is efficacious in the treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents; however, data on the effectiveness and safety of DEX in routine practice are scarce.

Objective

This study investigated the long-term effectiveness and safety of Attentin^® (immediate-release DEX) in children and adolescents with ADHD in routine practice.

Methods

ATTENTION was a multicenter, prospective, observational, non-interventional study that enrolled pediatric patients with ADHD (aged 6-17 years) with a clinically inadequate response to previous methylphenidate (MPH) treatment. Patients were assessed at baseline and two follow-up visits after approx. 6 and 12 months of DEX treatment. The primary endpoint was the investigator-rated ADHD rating scale IV (ADHD-RS-IV) total score change from baseline to the first follow-up visit.

Results

The study enrolled 140 patients (mean age: 11.2 years). Significant reductions in ADHD-RS-IV total scores were observed in the titration phase and were maintained up to the second follow-up visit. The mean ADHD-RS-IV total score change from baseline to the first follow-up visit was -11.9 (27.1 vs. 13.4, p < .001). Beneficial effects of DEX were observed on both ADHD-RS-IV subscales ('hyperactivity/impulsivity' and 'inattention') and in both children and adolescents. Clinical response, defined as a reduction in the ADHD-RS-IV total score of at least 30% at the first follow-up visit, was observed in 78.1% of patients. Patients reported an average onset of action of 36.2 minutes and an average duration of action of 6.5 hours after intake of the first dose of DEX in the morning. DEX was well tolerated. Small significant increases in mean systolic and diastolic blood pressure compared to baseline were observed.

Conclusions

Attentin^® is an effective and well-tolerated long-term treatment for pediatric ADHD patients with a clinically inadequate response to previous MPH treatment.

Neuroimaging in attention-deficit/hyperactivity disorder

PURPOSE OF REVIEW

Neuroimaging research on attention-deficit/hyperactivity disorder (ADHD) continues growing in extent and complexity, although it has yet to become clinically meaningful. We review recent MRI research on ADHD, to identify robust findings, current trends and challenges.

RECENT FINDINGS

We identified 40 publications between January 2019 and September 2020 reporting or reviewing MRI research on ADHD. Four meta-analyses have presented conflicting results regarding across-study convergence of functional and resting-state functional (fMRI and R-fMRI) studies on ADHD. On the other hand, the Enhancing NeuroImaging Genetics Through Meta-Analysis international consortium has identified statistically robust albeit small differences in structural brain cortical and subcortical indices in children with ADHD versus typically developing controls. Other international consortia are harnessing open-science efforts and multimodal data (imaging, genetics, phenotypic) to shed light on the complex interplay of genetics, environment, and development in the pathophysiology of ADHD. We note growing research in 'prediction' science, which applies machine-learning analysis to identify biomarkers of disease based on big data.

SUMMARY

Neuroimaging in ADHD is still far from informing clinical practice. Current large-scale, multimodal, and open-science initiatives represent promising paths toward untangling the neurobiology of ADHD.

Autism and attention-deficit/hyperactivity disorders and symptoms in children with neurofibromatosis type 1

AIM

To evaluate if autism symptoms and diagnoses are more common in children with neurofibromatosis type 1 (NF1) than in typically developing children, to which levels, and to determine if co-occurring attention-deficit/hyperactivity disorder (ADHD) symptomatology accounts for this increase.

METHOD

We searched hospital electronic medical records (EMR) for International Classification of Diseases, 10th Revision NF1 and co-occurring diagnoses codes. We recruited a subsample of 45 children (mean age 9y 2mo; SD 2y 7mo; range 5-12y; 22 males, 23 females) and collected parental reports of autism symptomatology, adaptive behavior, and behavioral problems that were compared to those of 360 age- and sex-matched controls from the Simons Simplex Collection (SSC) with autism spectrum disorder (ASD; SSC-ASD) or typically developing (SSC-TD).

RESULTS

The EMR search identified 968 children with NF1; 8.8% had ADHD and 2.1% had ASD co-occurring diagnoses. In the subsample, the mean autism scale score for participants with NF1 was below cut-off for significant autism symptoms. Participants with NF1 had significantly more autism and behavioral symptoms than SSC-TD participants, and significantly less than SSC-ASD participants, with one exception: ADHD symptom levels were similar to those of SSC-ASD participants. In analyses that controlled for internalizing, ADHD, and communication scores, the difference in autism symptom levels between participants with NF1 and typically developing controls disappeared almost entirely.

INTERPRETATION

Our results do not support an association between NF1 and autism, both at the symptom and disorder levels.

WHAT THIS PAPER ADDS

Diagnoses of attention-deficit/hyperactivity disorder (ADHD) were more common in children with neurofibromatosis type 1 (NF1) than in the general child population. Diagnoses of autism spectrum disorder were no more common in children with NF1 than in the general child population. Increases in autism symptoms did not reach clinically significant thresholds. Co-occurring ADHD symptoms accounted for increased autism questionnaire scores. Adaptive behavior in participants with NF1 showed normal socialization but lower communication proficiency.