Correlates of Anxiety in 6- to 8-Year-Old Children With ADHD: A Community-Based Study

Inattention symptom severity and cognitive processes in children at risk of ADHD: the moderating role of separation anxiety

Impairments in cognitive processes and their associations with dimensional measures of inattention, hyperactivity-impulsivity and anxiety were examined in children at risk of Attention-Deficit Hyperactivity Disorder. Children referred by teachers for exhibiting ADHD-type problems (n = 116; 43 meeting full diagnostic criteria for ADHD; 4-8 years) completed computerized tasks measuring episodic memory, response inhibition, visuomotor control and sustained attention, while parents were interviewed (DAWBA) to assess ADHD and anxiety symptoms. Of the 116 children assessed, 72% exhibited impaired cognitive processes; 47% had impaired visuomotor control, 37% impaired response inhibition, and 35% had impaired episodic memory. Correlational and hierarchical regression analyses using our final analytic sample (i.e., children who completed all cognitive tasks and a vocabulary assessment, n = 114) showed that poorer task performance and greater within-subject variability were significantly associated with more severe inattention symptoms but not with hyperactivity-impulsivity severity. Symptoms of separation anxiety, which were reported in over half of the sample, moderated associations between inattention and episodic memory, and between inattention and inhibition. Only children without separation anxiety showed significant correlations between ADHD symptoms and poor performance. However, separation anxiety had no moderating effect on associations between inattention and visuomotor control or sustaining attention. Children exhibiting signs of ADHD show impairments across a range of cognitive tasks. Further research to improve our understanding of these processes may be useful in the development of early interventions. Our results suggest that separation anxiety should be taken into account when considering interventions to address emerging neuropsychological deficits associated with this disorder.

Evaluating the effect of R-Baclofen and LP-211 on autistic behavior of the BTBR and Fmr1-KO mouse models

Introduction

Autism spectrum disorder (ASD) is a persistent neurodevelopmental condition characterized by two core behavioral symptoms: impaired social communication and interaction, as well as stereotypic, repetitive behavior. No distinct cause of ASD is known so far; however, excitatory/inhibitory imbalance and a disturbed serotoninergic transmission have been identified as prominent candidates responsible for ASD etiology.

Methods

The GABAB receptor agonist R-Baclofen and the selective agonist for the 5HT7 serotonin receptor LP-211 have been reported to correct social deficits and repetitive behaviors in mouse models of ASD. To evaluate the efficacy of these compounds in more details, we treated BTBR T+ Itpr3tf/J and B6.129P2-Fmr1tm1Cgr/J mice acutely with R-Baclofen or LP-211 and evaluated the behavior of animals in a series of tests.

Results

BTBR mice showed motor deficits, elevated anxiety, and highly repetitive behavior of self-grooming. Fmr1-KO mice exhibited decreased anxiety and hyperactivity. Additionally, Fmr1-KO mice’s ultrasonic vocalizations were impaired suggesting a reduced social interest and communication of this strain. Acute LP-211 administration did not affect the behavioral abnormalities observed in BTBR mice but improved repetitive behavior in Fmr1-KO mice and showed a trend to change anxiety of this strain. Acute R-Baclofen treatment improved repetitive behavior only in Fmr1-KO mice.

Conclusion

Our results add value to the current available data on these mouse models and the respective compounds. Yet, additional studies are needed to further test R-Baclofen and LP-211 as potential treatments for ASD therapy.

Effects of Methylphenidate on the Dopamine Transporter and Beyond

The dopamine transporter (DAT) is the main target of methylphenidate (MPH), which remains the number one drug prescribed worldwide for the treatment of Attention-Deficit Hyperactivity Disorder (ADHD). In addition, abnormalities of the DAT have been widely associated with ADHD. Based on clinical and preclinical studies, the direction of DAT abnormalities in ADHD are, however, still unclear. Moreover, chronic treatment of MPH has been shown to increase brain DAT expression in both animals and ADHD patients, suggesting that findings of overexpressed levels of DAT in ADHD patients are possibly attributable to the effects of long-term MPH treatment rather than the pathology of the condition itself. In this chapter, we will discuss some of the effects exerted by MPH, which are related to its actions on catecholamine protein targets and brain metabolites, together with genes and proteins mediating neuronal plasticity. For this purpose, we present data from biochemical, proton nuclear magnetic resonance spectroscopy (¹H-NMR) and gene/protein expression studies. Overall, results of the studies discussed in this chapter show that MPH has a complex biological/pharmacological action well beyond the DAT.

Prenatal and perinatal risk factors for anxiety disorders among children and adolescents: A systematic review

BACKGROUND

Prenatal and perinatal risk factors for anxiety disorders have rarely been studied, even though they are highly prevalent in children and adolescents. It is important to identify the common risk factors, so that targeted preventive care and early interventions can be provided.

METHODS

A systematic review of the PubMed and PsycInfo databases was conducted to 25 October 2019, according to the Preferred Reporting Items of Systematic Reviews and Meta-analyses guidelines. The protocol was registered on the Prospective Register of Systematic Reviews and the quality assessment was carried out using the Joanna Briggs tools.

RESULTS

The review identified 31 studies from eight countries, including three register studies. Cohort sizes ranged from 69 to 89,404 and diagnoses cases ranged from 4 to 7867. Although various risk factors had been researched, only few of them had been repeatedly studied and the findings were highly inconsistent. The associations between the different risk factors and anxiety disorders seemed weak compared to many other psychiatric disorders, but preterm birth and maternal somatic illnesses may increase the risk for anxiety disorders in offspring.

LIMITATIONS

The studies varied considerably by study design, risk factors and anxiety disorders studied, sample sizes and follow up periods.

CONCLUSIONS

Prenatal and perinatal risk factors for anxiety disorders have been under-researched, compared to other psychiatric disorders. Our systematic review found weak links to prenatal events, but flagged up preterm birth and maternal somatic illnesses as possible avenues for future research.

Does the treatment of anxiety in children with Attention-Deficit/Hyperactivity Disorder (ADHD) using cognitive behavioral therapy improve child and family outcomes? Protocol for a randomized controlled trial

BACKGROUND

Up to 60% of children with Attention-Deficit/Hyperactivity Disorder (ADHD) meet diagnostic criteria for at least one anxiety disorder, including Social, Generalized and/or Separation Disorder. Anxiety in children with ADHD has been shown to be associated with poorer child and family functioning. Small pilot studies suggest that treating anxiety in children with ADHD using cognitive-behavioral therapy (CBT) has promising benefits. In a fully powered randomized controlled trial (RCT), we aim to investigate the efficacy of an existing CBT intervention adapted for children with ADHD and comorbid anxiety compared with usual care.

METHODS

This RCT is recruiting children aged 8-12 years (N = 228) from pediatrician practices in Victoria, Australia. Eligibility criteria include meeting full diagnostic criteria for ADHD and at least one anxiety disorder (Generalized, Separation or Social). Eligible children are randomized to receive a 10 session CBT intervention (Cool Kids) versus usual clinical care from their pediatrician. The intervention focuses on building child and parent skills and strategies to manage anxiety and associated impairments including cognitive restructuring and graded exposure. Minor adaptations have been made to the delivery of the intervention to meet the needs of children with ADHD including increased use of visual materials and breaks between activities. The primary outcome is change in the proportion of children meeting diagnostic criteria for an anxiety disorder at 5 months randomization. This will be assessed via diagnostic interview with the child's parent (Anxiety Disorders Interview Schedule for Children V) conducted by a researcher blinded to intervention condition. Secondary outcomes include a range of child (e.g., anxiety symptoms, ADHD severity, behavior, quality of life, sleep, cognitive functioning, school attendance) and parent (e.g., mental health, parenting behaviors, work attendance) domains of functioning assessed at 5 and 12 months post-randomization. Outcomes will be analyzed using logistic and mixed effects regression.

DISCUSSION

The results from this study will provide evidence on whether treating comorbid anxiety in children with ADHD using a CBT approach leads to improvements in anxiety and/or broader functional outcomes.

TRIAL REGISTRATION

This trial was prospectively registered: Current Controlled Trials ISRCTN59518816 (https://doi.org/10.1186/ISRCTN59518816). The trial was first registered 29/9/15 and last updated 15/1/19.

Social anxiety is associated with poorer peer functioning for girls but not boys with ADHD

There is mixed evidence for whether or not co-occurring anxiety is associated with poorer peer functioning in children with attention-deficit/hyperactivity disorder (ADHD), which may be partly due to studies typically using a global measure of anxiety and failing to consider possible sex differences. The present study examined child-reported social anxiety in relation to peer functioning and whether this association differs by sex in 93 children (66% male; ages 8-12) with ADHD. Children, parents, and teachers completed a measure of social acceptance, and teachers also completed measures of asociality, peer exclusion, peer dislike, and peer ignoring. Regression analyses examined the interaction between social anxiety and sex in relation to the peer functioning variables, with age, race, ADHD subtype, and oppositional defiant disorder symptoms included as covariates. Social anxiety was associated with lower parent-reported social acceptance, with no sex differences in the association. However, significant interaction effects were found for child- and teacher-rated social acceptance, as well as peer exclusion and peer ignoring such that social anxiety was associated with less competence, more exclusion, and greater ignoring for girls but not boys. Findings indicate that social anxiety is associated with poorer peer functioning for girls more so than boys with ADHD.

1H NMR-based metabolomics reveals neurochemical alterations in the brain of adolescent rats following acute methylphenidate administration

The psychostimulant methylphenidate (MPH) is increasingly used in the treatment of attention deficit hyperactivity disorder (ADHD). While there is little evidence for common brain pathology in ADHD, some studies suggest a right hemisphere dysfunction among people diagnosed with the condition. However, in spite of the high usage of MPH in children and adolescents, its mechanism of action is poorly understood. Given that MPH blocks the neuronal transporters for dopamine and noradrenaline, most research into the effects of MPH on the brain has largely focused on these two monoamine neurotransmitter systems. Interestingly, recent studies have demonstrated metabolic changes in the brain of ADHD patients, but the impact of MPH on endogenous brain metabolites remains unclear. In this study, a proton nuclear magnetic resonance (¹H NMR)-based metabolomics approach was employed to investigate the effects of MPH on brain biomolecules. Adolescent male Sprague Dawley rats were injected intraperitoneally with MPH (5.0 mg/kg) or saline (1.0 ml/kg), and cerebral extracts from the left and right hemispheres were analysed. A total of 22 variables (representing 13 distinct metabolites) were significantly increased in the MPH-treated samples relative to the saline-treated controls. The upregulated metabolites included: amino acid neurotransmitters such as GABA, glutamate and aspartate; large neutral amino acids (LNAA), including the aromatic amino acids (AAA) tyrosine and phenylalanine, both of which are involved in the metabolism of dopamine and noradrenaline; and metabolites associated with energy and cell membrane dynamics, such as creatine and myo-inositol. No significant differences in metabolite concentrations were found between the left and right cerebral hemispheres. These findings provide new insights into the mechanisms of action of the anti-ADHD drug MPH.