A Comparison between Children with ADHD and Children with Epilepsy in Self-Esteem and Parental Stress Level

Attention-deficit/hyperactivity disorder (ADHD) is frequently associated with negative psychological outcomes. This study explores the relationship between self-esteem, ADHD symptoms and parental stress. It compares children with ADHD, children with epilepsy (E) and typical developmental controls (TD). Participants included 65 children (aged 9-12 yrs) and their parents. The assessment was conducted by Multidimensional Self-Concept Scale (MSCS), Parent Stress Index (PSI) and Conners' Parent Rating Scales–Revised. Significant differences were found in Social, Competence and Academic areas of self-esteem between children with ADHD, with E and TD. Moreover, parents of children with ADHD showed a higher overall stress than both other groups. In conclusion, it seems important to evaluate the psychological aspects of ADHD con-dition, both in children and in parents, in order to suggest an individual multimodal treatment.

Managing attention-deficit/hyperactivity disorder in children and adolescents

Attention-deficit/hyperactivity disorder (ADHD) is the most frequently diagnosed neurodevelopmental disorder; 6.4 million children and adolescents have been diagnosed with ADHD as of 2011. However, only 3.5 million children and adolescents are taking medication for ADHD. Adolescents with ADHD are much less willing to pursue or adhere to medication or psychosocial therapy, often because of their perceptions of side effects or perceived value of treatment, which places them at greater risk for difficulties at school, work, and home environments. Providing adolescents with increased autonomy through patient-centered approaches can increase their involvement and ability to manage their ADHD symptoms and treatment.

Electroencephalography and externalizing behavior: a meta-analysis

Electroencephalography (EEG) has been used to examine the possibility of dysfunctional brain activity in externalizing behavior, but findings across studies have been inconsistent. Furthermore, studies of attention-deficit/hyperactivity disorder (ADHD) versus other externalizing behaviors, such as disruptive behavior disorders or antisocial behavior, have developed parallel literatures. The purpose of the present study was to reconcile these two literatures. A meta-analysis of 62 studies of EEG power at rest in relationship to externalizing behaviors was performed. Results of the meta-analyses showed significantly higher delta (Hedges's g=0.25) and theta power (g=0.40) and lower beta power (g=-0.22) in externalizing participants compared to controls. Alpha (g=-0.26) and gamma power (g=-0.26) were marginally lower in externalizing samples. Results were not moderated by type of externalizing behavior. Overall, the results of the meta-analyses were consistent with the hypoarousal theory of externalizing behavior.

Association between GUC2C and ADHD: evidence from both categorical and quantitative traits

Guanylyl cyclase-C knock-out mice exhibit hyperactivity and attention deficits. We investigated seven single nucleotide polymorphisms (SNPs) of Guanylate cyclase 2C gene (GUC2C) in 381 ADHD trios and 382 healthy controls. Transmission disequilibrium tests (TDT), case-control studies and quantitative analyses indicated association between GUC2C with ADHD and its core symptoms.

Efficacy and safety of extended-release guanfacine hydrochloride in children and adolescents with attention-deficit/hyperactivity disorder: a randomized, controlled, phase III trial

Guanfacine extended-release (GXR), a selective α2A-adrenergic agonist, is a non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). This study assessed the efficacy (symptoms and function) and safety of dose-optimized GXR compared with placebo in children and adolescents with ADHD. An atomoxetine (ATX) arm was included to provide reference data against placebo. Patients (6-17 years) were randomized at baseline to dose-optimized GXR (0.05-0.12mg/kg/day - 6-12 years: 1-4mg/day; 13-17 years: 1-7mg/day), ATX (10-100mg/day) or placebo for 4 or 7 weeks. The primary efficacy measure was change from baseline in ADHD Rating Scale version IV (ADHD-RS-IV). Key secondary measures were Clinical Global Impression-Improvement (CGI-I) and the Weiss Functional Impairment Rating Scale-Parent Report (WFIRS-P; learning and school, and family domains). Safety assessments included treatment-emergent adverse events (TEAEs), electrocardiograms and vital signs. A total of 272 (80.5%) patients from Europe, the USA and Canada completed the study. Significant differences were observed in least squares mean change from baseline in ADHD-RS-IV total score (placebo-adjusted differences) (GXR: [-8.9, p<0.001]; ATX: [-3.8, p<0.05]), the difference from placebo in the percentage of patients showing improvement (1 ['very much improved'] or 2 ['much improved']) for CGI-I (GXR: [23.7, p<0.001]; ATX: [12.1, p<0.05]), WFIRS-P learning and school domain (GXR: [-0.22, p<0.01]; ATX: [-0.16, p<0.05]) and WFIRS-P family domain (GXR: [-0.21, p<0.01]; ATX: [-0.09, p=0.242]). Most common TEAEs for GXR were somnolence, headache and fatigue; 70.1% of GXR subjects reported mild-to-moderate TEAEs. GXR was effective and well tolerated in children and adolescents with ADHD.

Inattention symptoms and the diagnosis of comorbid attention-deficit/hyperactivity disorder among youth with generalized anxiety disorder

Generalized anxiety disorder (GAD) and attention-deficit/hyperactivity disorder (ADHD) commonly co-occur in childhood. Inattention symptoms can be hallmarks of both conditions, however assessment tools of inattention may not effectively distinguish between the two conditions. The present study used receiver operating characteristic (ROC) analyses to examine the high-end specificity of the Attention Problems Scale of the Child Behavior Checklist (CBCL) for detecting comorbid ADHD among youth with GAD (N=46). Results support the utility of the Attention Problems Scale for accurately distinguishing between the two groups (AUC=.84, SE=.06). Specifically, a cut score of 63 achieved the most favorable values across diagnostic utility indices; 74% of GAD youth with ADHD scored above this cutoff and 91% of GAD youth without ADHD scored below this cutoff. Findings provide support for the use of the CBCL Attention Problems Scale to supplement diagnostic interviews and identify inattention associated with ADHD among GAD youth.

A multimodal MRI study of the hippocampus in medication-naive children with ADHD: what connects ADHD and depression?

Children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for developing depression. The neurobiological substrates that convey this risk remain poorly understood. On the basis of considerable data implicating hippocampal abnormalities in depressive disorders, we aimed to explore the relationship between the hippocampus and levels of depressive symptomatology in ADHD. We used magnetic resonance imaging (MRI) to examine the volumes and resting-state functional connectivity of the hippocampus in a sample of 32 medication naive children with ADHD (ages 6 - 13) and 33 age- and sex-matched healthy control (HC) participants. Compared with the HC participants, the participants with ADHD had (i) reduced volumes of the left hippocampus and (ii) reduced functional connectivity between the left hippocampus and the left orbitofrontal cortex (OFC); these hippocampal effects were associated with more severe depressive symptoms, even after controlling for the severity of inattentive and hyperactive/impulsive symptoms. Altered hippocampal structure and connectivity were not associated with anxiety or more general internalizing symptoms. Though preliminary, these findings suggest that the relationship between hippocampal anomalies and ADHD youth's susceptibility to developing depression and other mood disorders may merit further investigation with follow-up longitudinal research.

Behavioural treatment recommendations in clinical practice guidelines for attention-deficit/hyperactivity disorder: a scoping review

BACKGROUND

The extent of behavioural treatment recommendations described in attention-deficit/hyperactivity disorder (ADHD) practice guidelines has not been examined.

METHOD

A scoping review identified eight agency-based ADHD practice guidelines. Key components of behavioural treatment recommendations were summarized.

RESULTS

All guidelines mentioned behavioural treatment as a consideration for managing ADHD, however, the extent to which they were detailed varied. Most guidelines provided lists of behavioural techniques but with minimal specifics regarding treatment delivery.

CONCLUSIONS

There is far less detailing of behavioural approaches compared to pharmacological treatments for ADHD. Greater detailing of evidence-based behavioural approaches may foster improved delivery of high-quality behaviour treatment.

Effect of treadmill exercise on social interaction and tyrosine hydroxylase expression in the attention-deficit/ hyperactivity disorder rats

Attention-deficit/hyperactivity disorder (ADHD) involves clinically heterogeneous dysfunctions of sustained attention, with behavioral hyper-activity and impulsivity. The exact underlying mechanisms of ADHD are not known, however, impairment of dopaminergic system in the nigrostriatal pathway was suggested as the one of the possible mechanisms of ADHD. Tyrosine hydroxylase (TH) is the rate-limiting enzyme that is involved in the synthesis of dopamine. Spontaneous hypertensive rats have been used as the animal model for ADHD. Physical exercise is known to restore the brain functions disrupted by several neurode-generative and psychiatric disorders. In the present study, we investigated whether treadmill exercise exerts therapeutic effect on ADHD. Social interaction test for the evaluation of impulsivity was performed using spontaneous hypertensive rats. TH expressions in the substantia nigra and striatum were evaluated by immunohistochemistry. In the present results, the rats of ADHD model showed hyper-social behaviors. TH expressions in the substantia nigra and striatum were decreased in the rats of ADHD model. Treadmill exercise alleviated hyper-social behaviors in the ADHD rats. TH expressions of ADHD rats were also enhanced by treadmill exercise. Here in this study, we showed that treadmill exercise effectively alleviates the ADHD-induced symptoms through enhancing of TH expression in the brain.

Categorization behaviour in adults, adolescents, and attention-deficit/hyperactivity disorder adolescents: A comparative investigation

Although significant progress has been made with respect to our understanding of categorization and concept learning behaviour in adults, much less is known about how this key capacity plays out with respect to more restrictive populations. This is unfortunate because much may be revealed about the nature of concept learning by examining the limits exhibited by special populations. With this tenet in mind, in what follows, we investigated key aspects of concept learning in terms of the unexplored comparative performance of three populations-adults, adolescents, and adolescents with attention-deficit/hyperactivity disorder (ADHD). To do so, we employed a novel parainformative experimental task involving categorical stimuli with four objects defined over three dimensions. The learning difficulty ordering for these types of three-dimensional stimuli has proven robust and has been replicated by several researchers. Indeed, in our experiment, we observed the same concept learning ordering in adults and adolescents, but not in ADHD adolescents: For example, the latter group showed greatly impaired categorization performance on stimuli characterized by an "exclusive-or" rule. However, categorization performance on such type of stimuli indicated good reliability in discriminating between adolescents with and without ADHD (receiver-operating characteristic, ROC = .82). We accurately predicted and accounted for these results using generalized invariance structure theory (GIST; Vigo, 2013. The GIST of concepts. Cognition, 129, 138-162), which posits that organisms detect invariance patterns in stimuli that are necessary precursors to concept formation.

Genetic risk for attention-deficit/hyperactivity disorder contributes to neurodevelopmental traits in the general population

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) can be viewed as the extreme end of traits in the general population. Epidemiological and twin studies suggest that ADHD frequently co-occurs with and shares genetic susceptibility with autism spectrum disorder (ASD) and ASD-related traits. The aims of this study were to determine whether a composite of common molecular genetic variants, previously found to be associated with clinically diagnosed ADHD, predicts ADHD and ASD-related traits in the general population.

METHODS

Polygenic risk scores were calculated in the Avon Longitudinal Study of Parents and Children (ALSPAC) population sample (N = 8229) based on a discovery case-control genome-wide association study of childhood ADHD. Regression analyses were used to assess whether polygenic scores predicted ADHD traits and ASD-related measures (pragmatic language abilities and social cognition) in the ALSPAC sample. Polygenic scores were also compared in boys and girls endorsing any (rating ≥ 1) ADHD item (n = 3623).

RESULTS

Polygenic risk for ADHD showed a positive association with ADHD traits (hyperactive-impulsive, p = .0039; inattentive, p = .037). Polygenic risk for ADHD was also negatively associated with pragmatic language abilities (p = .037) but not with social cognition (p = .43). In children with a rating ≥ 1 for ADHD traits, girls had a higher polygenic score than boys (p = .003).

CONCLUSIONS

These findings provide molecular genetic evidence that risk alleles for the categorical disorder of ADHD influence hyperactive-impulsive and attentional traits in the general population. The results further suggest that common genetic variation that contributes to ADHD diagnosis may also influence ASD-related traits, which at their extreme are a characteristic feature of ASD.

The co-occurrence of attention-deficit/hyperactivity disorder and unipolar depression in children and adolescents: a meta-analytic review

This paper reviews the empirical literature on the association between attention-deficit/hyperactivity disorder (ADHD) and depression (i.e., unipolar depressive disorders and symptoms) among children and adolescents. Findings from cross-sectional and longitudinal studies published on the co-occurrence of ADHD and depression were summarized and subjected to a meta-analysis. Results (k=29, N=8755; rbar=0.22) indicated that ADHD and depression were positively related, but substantial variability existed across the studies. Subgroup analyses indicated medium positive effects for cross-sectional studies, studies that operationalized ADHD based on DSM-III or DSM-IV diagnostic criteria, and studies that did not include teacher report in the assessment of ADHD. Subgroup analyses showed a large positive effect for studies that operationalized ADHD based on DSM-III-R criteria and studies using clinic referred samples. In contrast, subgroup analyses indicated a small negative and/or unreliable association between ADHD and depression for longitudinal studies, studies using DSM-II diagnostic criteria for hyperkinetic reaction of childhood or used a dichotomous motor hyperactivity criterion, studies that used nonreferred samples, and studies including teacher report in the assessment of ADHD. When studies that used DSM-II diagnostic criteria were removed, a reliable medium effect was found for studies that included teacher report. Similarly when the study that used idiosyncratic methods of diagnosing ADHD was excluded, a reliable medium effect was found for studies that used nonreferred samples. Potential explanations for the findings are discussed, including explanations based on sampling and base rates, artifacts of diagnostic criteria, inaccurate diagnostic boundaries, and etiological relationships. Directions for future research and clinical implications are discussed.

School-based interventions for elementary school students with ADHD

Children with attention-deficit/hyperactivity disorder (ADHD) experience significant difficulties with behavior, social functioning, and academic performance in elementary school classrooms. Although psychotropic medication may enhance classroom behavior, pharmacologic treatment is rarely sufficient in addressing the many challenges encountered by individuals with ADHD in school settings. This article describes 3 evidence-based strategies including behavioral, academic, and self-regulation interventions. Future directions for research on school-based interventions are discussed.

Summer Treatment Programs for Youth with Attention-deficit/hyperactivity Disorder

Children with attention-deficit/hyperactivity disorder (ADHD) require intensive treatments to remediate functional impairments and promote the development of adaptive skills. The summer treatment program (STP) is an exemplar of intensive treatment of ADHD. STP intervention components include a reward and response-cost point system, time-out, use of antecedent control (clear commands, establishment of rules and routines), and liberal praise and rewards for appropriate behavior. Parents also participate in parent management training programming to learn how to implement similar procedures within the home setting. There is strong evidence supporting the efficacy of the STP as an intervention for ADHD.

An integrated dietary/nutritional approach to ADHD

Dietary and herbal interventions for attention-deficit/hyperactivity disorder (ADHD) have been proposed by practitioners of Western medicine and traditional Chinese medicine. Children who are suspected to have nutritional deficiencies, insufficiencies, and/or food allergies should be evaluated and, if the suspicion is confirmed, treated with supplementation or specific food elimination as part of standard care. Limited research exists on the efficacy and safety of dietary intervention as an adjunct to conventional medication; thus, improvement and side effects should be closely monitored.

Traditional Chinese medicine in the treatment of ADHD: a review

This review covers an introduction of traditional Chinese medicine (TCM) in treating attention-deficit/hyperactivity disorder (ADHD), focusing on the traditional theoretic basis from the perspective of TCM regarding ADHD's cause, pathogenesis, methods of syndrome differentiation, and rationale for treatment. The authors present commonly accepted and successfully practiced clinical procedures used in China for diagnosis and treatment of ADHD by TCM clinicians along with the supportive clinical evidence. The authors hope to inspire more research to better understand the mechanisms underlying the therapies and to promote appropriate incorporation of TCM therapies with Western pharmacologic treatment to better help patients with ADHD.

Healthy body, healthy mind?: the effectiveness of physical activity to treat ADHD in children

Data from animal studies provide convincing evidence that physical exercise enhances brain development and neurobehavioral functioning in areas believed to be impaired in children with attention-deficit/hyperactivity disorder (ADHD). To a lesser but still compelling extent, results from studies in typically developing children and adults indicate beneficial effects of exercise on many of the neurocognitive functions that have been shown to be impaired in children with ADHD. Together, these data provide a strong rationale for why a program of structured physical exercise might serve as an effective intervention for children with ADHD.

Behavior management for school-aged children with ADHD

Behavior management treatments are the most commonly used nonpharmacologic approaches for treating attention-deficit/hyperactivity disorder (ADHD) and associated impairments. This review focuses on behavioral parent training interventions for school-age children in the home setting and adjunctive treatments developed to extend effects across settings. Empirical support includes numerous randomized clinical trials, systematic reviews, and meta-analyses showing positive effects of these interventions on child compliance, ADHD symptoms and impairments, parent-child interactions, parenting and parenting stress. These studies support categorization of behavior management treatment as a well-established, evidence-based treatment of ADHD. Factors for consideration in clinical decision making and directions for research are provided.

Molecular genetic studies of ADHD and its candidate genes: a review

Attention-deficit/hyperactivity disorder (ADHD) is a common childhood-onset psychiatric disorder with high heritability. In recent years, numerous molecular genetic studies have been published to investigate susceptibility loci for ADHD. These results brought valuable candidates for further research, but they also presented great challenge for profound understanding of genetic data and general patterns of current molecular genetic studies of ADHD since they are scattered and heterogeneous. In this review, we presented a retrospective review of more than 300 molecular genetic studies for ADHD from two aspects: (1) the main achievements of various studies were summarized, including linkage studies, candidate-gene association studies, genome-wide association studies and genome-wide copy number variation studies, with a special focus on general patterns of study design and common sample features; (2) candidate genes for ADHD have been systematically evaluated in three ways for better utilization. The thorough summary of the achievements from various studies will provide an overview of the research status of molecular genetics studies for ADHD. Meanwhile, the analysis of general patterns and sample characteristics on the basis of these studies, as well as the integrative review of candidate ADHD genes, will propose new clues and directions for future experiment design.

Psychometric properties of Japanese version of the Swanson, Nolan, and Pelham, version-IV Scale-Teacher Form: a study of school children in community samples

BACKGROUND

Psychometric properties of The Japanese version of Swanson, Nolan, and Pelham IV scale (SNAP-IV)-Teacher Form were examined in this study.

METHOD

Community samples of 1296 children (Grade 1-9, boys 52.9%) were collected from public elementary/middle schools in suburban areas. Teachers rated their children's behavior using Japanese version of SNAP-IV-Teacher Form and Strength and Difficulties Questionnaire (SDQ).

RESULTS

A three-factor structure model, which was equivalent with AD/HD symptoms subscales (inattention, hyperactivity/impulsivity) and oppositional-defiant disorder symptoms subscale was obtained and confirmed in an explorative/confirmative factorial analysis (Goodness-of-Fit Index=0.913, Comparative Fit Index=0.959, root mean square error of approximation=0.056). The current version of the SNAP-IV-Teacher Form demonstrated good test-retest reliability (intra-class correlation=0.752-0.822), high internal consistency (Cronbach's α=0.933-0.952), significant correlations with relevant subscales of Japanese version of SDQ, and typical effects of age and gender on those subscales.

CONCLUSION

The current study indicates that the Japanese version of SNAP-IV-Teacher Form is a reliable and valid instrument for rating symptoms related to AD/HD and ODD.

Differential oscillatory electroencephalogram between attention-deficit/hyperactivity disorder subtypes and typically developing adolescents

BACKGROUND

A neurobiological-based classification of attention-deficit/hyperactivity disorder (ADHD) subtypes has thus far remained elusive. The aim of this study was to use oscillatory changes in the electroencephalogram (EEG) related to informative cue processing, motor preparation, and top-down control to investigate neurophysiological differences between typically developing (TD) adolescents, and those diagnosed with predominantly inattentive (IA) or combined (CB) (associated with symptoms of inattention as well as impulsivity/hyperactivity) subtypes of ADHD.

METHODS

The EEG was recorded from 57 rigorously screened adolescents (12 to 17 years of age; 23 TD, 17 IA, and 17 CB), while they performed a cued flanker task. We examined the oscillatory changes in theta (3-5 Hz), alpha (8-12 Hz), and beta (22-25 Hz) EEG bands after cues that informed participants with which hand they would subsequently be required to respond.

RESULTS

Relative to TD adolescents, the IA group showed significantly less postcue alpha suppression, suggesting diminished processing of the cue in the visual cortex, whereas the CB group showed significantly less beta suppression at the electrode contralateral to the cued response hand, suggesting poor motor planning. Finally, both ADHD subtypes showed weak functional connectivity between frontal theta and posterior alpha, suggesting common top-down control impairment.

CONCLUSIONS

We found both distinct and common task-related neurophysiological impairments in ADHD subtypes. Our results suggest that task-induced changes in EEG oscillations provide an objective measure, which in conjunction with other sources of information might help distinguish between ADHD subtypes and therefore aid in diagnoses and evaluation of treatment.

A Comparison between School and Home Rating Scales and Reliability-Validity of the Scales-the Scales for Diagnosing Attention-Deficit/Hyperactivity Disorder

INTRODUCTION

The purpose of the present research is to compare the Turkish translations of school and home versions of the Scales for Diagnosing Attention-Deficit/Hyperactivity Disorder (SCALES) developed by Ryser and McConnell with respect to age and gender and to examine the correlation between the two scales.

METHOD

The research was conducted with 102 teachers and parents of 891 children aged between 5.0 and 14.11 years. 656 scale forms of parents returned to us were included in the study. The teachers filled in teacher information form, child information form, SCALES-School Rating Scale and the Turkish version of Conners' Teacher Rating Scale. The parents filled in family information form, child information form and SCALES-Home Rating Scale and the Turkish version of the Conners' Home Rating Scale.

RESULTS

When SCALES-Home Rating Scale and SCALES-School Rating Scale scores of each age group were compared using t-test, it was observed that the difference in all sub-scale scores in the 5-9 age group was significant and it was also observed that in the 10-13 and 13+ age groups, the difference was significant only in the hyperactivity field. The correlation between SCALES-School Rating Scale and SCALES-Home Rating Scale was investigated. The correlation between sub-scales measuring the same abilities was found to be between 0.1 and 0.26.

CONCLUSION

We assume that the Turkish version of the SCALES is a valid and reliable instrument for diagnosing ADHD. Since SCALES-Home Rating Scale scores were higher than SCALES-School Rating Scale scores and the correlation between the two scales was low, we assume that the objectivity of parents' ratings was limited. Future validity studies on diagnosed children are needed.

Central nervous system processing of emotions in children with nocturnal enuresis and attention-deficit/hyperactivity disorder

AIM

Nocturnal enuresis (NE) and attention-deficit/hyperactivity disorder (ADHD) are common in childhood. We analysed the central processing of emotions in children with NE, ADHD, NE + ADHD and controls.

METHODS

We examined 13 children with NE, 13 with ADHD, 14 with NE + ADHD and 14 controls. Acoustic evoked potentials were recorded using standardised methodology. For the event-related potentials, positive, negative and neutral pictures were presented and time intervals of 250-450, 450-650 and 650-850 msec evaluated. Hypotheses were tested with repeated-measures analyses of variance.

RESULTS

In the frontal region, children with NE showed more intense responses to positive and negative pictures than controls measured with event-related potentials. Viewing positive pictures, children with NE + ADHD differed from children with ADHD in the central and parietal and for all types of stimuli in the parietal region. Children with NE + ADHD elicited the strongest responses. Children with ADHD did not differ from controls. There was an unspecific interaction effect of the acoustic evoked potentials in children with NE compared to the controls.

CONCLUSION

Children with NE processed emotions differently from children with ADHD and controls. Children with NE + ADHD processed emotions the most intense, displaying interaction effects of the central nervous system that cannot be explained by each disorder alone.

Preschool regulatory problems and attention-deficit/hyperactivity and cognitive deficits at school age in children born at risk: different phenotypes of dysregulation?

BACKGROUND

Early regulatory problems (RP), i.e., excessive crying, feeding, and sleeping difficulties, have been reported to be predictors of cognitive and attention-deficit/hyperactivity problems. However, previous studies had limitations such as small sample size or retrospective design.

AIM

To investigate whether persistent RP from infancy until preschool age are precursors of ADHD problems and cognitive deficits at school age.

STUDY DESIGN

A prospective study from birth to 8.5years of age.

SUBJECTS

1120 infants born at risk.

MEASURES

RP were assessed at 5months (i.e., excessive crying, feeding, and sleeping problems), 20, and 56months (i.e., eating and sleeping problems) via parent interviews and neurological examination. At 8.5years of age, IQ was assessed by a standard test (K-ABC), and ADHD problems by direct observations in the test situation and by the Mannheimer Parent Interview (MPI, DSM-IV diagnosis of ADHD).

RESULTS

23.8% of the sample born at risk had RP at least at two measurement points until preschool age. Persistent RP predicted lower IQ (β=-.17; 95% CI (-.21; -.10)), behaviour problems (β=-.10; 95% CI (-.15; -.03)), attention (OR 2.43; 95% CI (1.16; 5.09)) and hyperactivity problems (OR 3.10; 95% CI (1.29; 7.48)), and an ADHD diagnosis (OR 3.32; 95% CI (1.23; 8.98)) at school age, even when controlled for psychosocial and neurological confounders.

CONCLUSIONS

Early persistent RP increased the odds of ADHD and associated problems at school age, indicating a cascade model of development, i.e., infant behaviour problems provide the starting point of a trajectory of dysregulation through time.

Attention-deficit/hyperactivity disorder and attention impairment in children with benign childhood epilepsy with centrotemporal spikes

Attention-deficit/hyperactivity disorder (ADHD) is a common comorbidity in children with epilepsy and has a negative impact on behavior and learning. The purposes of this study were to quantify the prevalence of ADHD in benign childhood epilepsy with centrotemporal spikes (BCECTS) and to identify clinical factors that affect ADHD or attention impairment in patients with BCECTS. The medical records of 74 children (44 males) with neuropsychological examination from a total of 198 children diagnosed with BCECTS at Asan Medical Center were retrospectively reviewed. Electroclinical factors were compared across patients with ADHD and those without ADHD. Mean T-scores of the continuous performance test were compared across patients grouped according to various epilepsy characteristics. Forty-eight (64.9%) patients had ADHD. A history of febrile convulsion was more common in patients with ADHD than in patients without ADHD (p=0.049). Bilateral centrotemporal spikes on electroencephalogram were more common in patients receiving ADHD medication than in patients with untreated ADHD (p=0.004). Male patients, patients with frequent seizures prior to diagnosis, and patients with a high spike index (≥40/min) on sleep EEG at diagnosis had significantly lower visual selective attention (p<0.05). Children with BCECTS had a high prevalence of ADHD, and frequent seizures or interictal epileptiform abnormalities were closely related to impairment of visual selective attention in children with BCECTS, indicating the need for ADHD or attention impairment screening in children with BCECTS.

Transcranial oscillatory direct current stimulation during sleep improves declarative memory consolidation in children with attention-deficit/hyperactivity disorder to a level comparable to healthy controls

BACKGROUND

Slow oscillations (<1 Hz) during slow wave sleep (SWS) promote the consolidation of declarative memory. Children with attention-deficit/hyperactivity disorder (ADHD) have been shown to display deficits in sleep-dependent consolidation of declarative memory supposedly due to dysfunctional slow brain rhythms during SWS.

OBJECTIVE

Using transcranial oscillating direct current stimulation (toDCS) at 0.75 Hz, we investigated whether an externally triggered increase in slow oscillations during early SWS elevates memory performance in children with ADHD.

METHODS

12 children with ADHD underwent a toDCS and a sham condition in a double-blind crossover study design conducted in a sleep laboratory. Memory was tested using a 2D object-location task. In addition, 12 healthy children performed the same memory task in their home environment.

RESULTS

Stimulation enhanced slow oscillation power in children with ADHD and boosted memory performance to the same level as in healthy children.

CONCLUSION

These data indicate that increasing slow oscillation power during sleep by toDCS can alleviate declarative memory deficits in children with ADHD.

Traumatic brain injury-related attention deficits: treatment outcomes with lisdexamfetamine dimesylate (Vyvanse)

BACKGROUND AND OBJECTIVES

Attention deficits are often among the most persistent and debilitating impairments resulting from traumatic brain injury (TBI). This study examined the effects of lisdexamfetamine dimesylate (Vyvanse) in treating attention deficits due to moderate-to-severe TBI. It was the first study of lisdexamfetamine dimesylate with this population and, in fact, was the first controlled trial in this area examining a stimulant medication option other than methylphenidate.

METHODS

This was a 12-week, randomized, double-blind, placebo-controlled, cross-over trial. A total of 22 rigorously selected cases were enrolled, 13 of whom completed the trial. They were 16-42 years of age and had newly acquired attention deficits persisting for 6-34 months post-injury. They were assessed on a broad range of neuropsychological and behavioural measures at baseline, 6-weeks and at 12-weeks.

RESULTS AND CONCLUSIONS

Positive treatment effects were found involving selective measures of sustained attention, working memory, response speed stability and endurance and in aspects of executive functioning. No major problems with safety or tolerability were observed. Some moderating treatment effects were found from a broad range of pre-treatment subject characteristics and injury variables examined. Avenues for further research and treatment applications in this area are discussed.

Association between mechanical ventilation and neurodevelopmental disorders in a nationwide cohort of extremely low birth weight infants

Mechanical ventilation for preterm infants independently contributes to poor neurodevelopmental performance. However, few studies have investigated the association between the duration of mechanical ventilation and the risk for various developmental disorders in extremely low birth weight (ELBW) (<1000g) infants. Using a large nationwide database, we did a 10-year retrospective follow-up study to explore the effect of mechanical ventilation on the incidence of cerebral palsy (CP), autism spectrum disorder (ASD), intellectual disability (ID), and attention-deficit/hyperactivity disorder (ADHD) in ELBW infants born between 1998 and 2001. Seven hundred twenty-eight ELBW infants without diagnoses of brain insults or focal brain lesions in the initial hospital stay were identified and divided into three groups (days on ventilator: ≦2, 3-14, ≧15 days). After adjusting for demographic and medical factors, the infants in the ≧15 days group had higher risks for CP (adjusted hazard ratio: 2.66; 95% confidence interval: 1.50-4.59; p<0.001) and ADHD (adjusted hazard ratio: 1.95; 95% confidence interval: 1.02-3.76; p<0.05), than did infants in the ≦2 days group. The risk for ASD or ID was not significantly different between the three groups. We conclude that mechanical ventilation for ≧15 days increased the risk for CP and ADHD in ELBW infants even without significant neonatal brain damage. Developing a brain-protective respiratory support strategy in response to real-time cerebral hemodynamic and oxygenation changes has the potential to improve neurodevelopmental outcomes in ELBW infants.

Cocaine-seeking behavior in a genetic model of attention-deficit/hyperactivity disorder following adolescent methylphenidate or atomoxetine treatments

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is often comorbid with cocaine abuse. Controversy exists regarding long-term consequences of ADHD medications on cocaine abuse liability. Whereas childhood methylphenidate treatment may be preventative, methylphenidate in teens appears to further increase later cocaine abuse risk. In rodents, adolescent methylphenidate treatment further increases adult cocaine self-administration in the Spontaneously Hypertensive Rat (SHR) model of ADHD, whereas adolescent atomoxetine treatment does not. Effects of ADHD medications on cocaine cue reactivity, a critical component of addiction, are unknown.

METHODS

To investigate this, SHR, Wistar-Kyoto (inbred control) and Wistar (outbred control) rats received therapeutically relevant doses of methylphenidate (1.5 mg/kg, oral) and atomoxetine (0.3 mg/kg, intraperitoneal), or respective vehicles from post-natal day 28-55. Cocaine seeking, reflecting cue reactivity, was measured in adulthood during self-administration maintenance and cue-induced reinstatement tests conducted under a second-order schedule.

RESULTS

Compared to control strains, SHR earned more cocaine infusions, emitted more cocaine-seeking responses during maintenance and reinstatement testing, and required more sessions to reach the extinction criterion. Compared to vehicle, adolescent methylphenidate, but not atomoxetine, further increased cocaine intake during maintenance testing in SHR. Adolescent atomoxetine, but not methylphenidate, decreased cocaine seeking during reinstatement testing in SHR. Neither medication had effects on cocaine intake or cue reactivity in control strains.

CONCLUSIONS

The SHR successfully model ADHD and cocaine abuse comorbidity and show differential effects of adolescent ADHD medications on cocaine intake and cue reactivity during adulthood. Thus, SHR have heuristic value for assessing neurobiology underlying the ADHD phenotype and for evaluating pharmacotherapeutics for ADHD.

Shared familial transmission of autism spectrum and attention-deficit/hyperactivity disorders

BACKGROUND

To determine whether familial transmission is shared between autism spectrum disorders and attention-deficit/hyperactivity disorder, we assessed the prevalence, rates of comorbidity, and familial transmission of both disorders in a large population-based sample of children during a recent 7 year period.

METHODS

Study participants included all children born to parents with the Kaiser Permanente Northwest (KPNW) Health Plan between 1 January 1998 and 31 December 2004 (n = 35,073). Children and mothers with physician-identified autism spectrum disorders (ASD) and/or attention-deficit/hyperactivity disorder (ADHD) were identified via electronic medical records maintained for all KPNW members.

RESULTS

Among children aged 6-12 years, prevalence was 2.0% for ADHD and 0.8% for ASD; within those groups, 0.2% of the full sample (19% of the ASD sample and 9.6% of the ADHD sample) had co-occurring ASD and ADHD, when all children were included. When mothers had a diagnosis of ADHD, first born offspring were at 6-fold risk of ADHD alone (OR = 5.02, p < .0001) and at 2.5-fold risk of ASD alone (OR = 2.52, p < .01). Results were not accounted for by maternal age, child gestational age, child gender, and child race.

CONCLUSIONS

Autism spectrum disorders shares familial transmission with ADHD. ADHD and ASD have a partially overlapping diathesis.

Omega-3 fatty acid and nutrient deficits in adverse neurodevelopment and childhood behaviors

Nutritional insufficiencies of omega-3 highly unsaturated fatty acids (HUFAs) may have adverse effects on brain development and neurodevelopmental outcomes. A recent meta-analysis reported a small to modest effect size for the efficacy of omega-3 in youth. Several controlled trials of omega-3 HUFAs combined with micronutrients show sizable reductions in aggressive, antisocial, and violent behavior in youth and young adult prisoners. Studies of HUFAs in youth, however, remain lacking. As the evidence base for omega-3 HUFAs as potential psychiatric treatment develops, dietary adjustments to increase omega-3 and reduce omega-6 HUFA consumption are sensible recommendations based on general health considerations.

Treadmill exercise improves spatial learning ability by enhancing brain-derived neurotrophic factor expression in the attention-deficit/hyperactivity disorder rats

Attention-deficit/hyperactivity disorder (ADHD) patients show learning difficulty and impulsiveness. Exercise is known to improve learning ability and memory function. In the present study, we investigated the duration-dependence of the effect of treadmill exercise on spatial learning ability in relation with brain-derived neurotrophic factor (BDNF) expression in ADHD rats. For this study, radial 8-arm maze test and western blot for BDNF and tyrosine kinase B (TrkB) were performed. Spontaneous hypertensive rats were used as the ADHD rats and Wistar-Kyoto rats were used as the control rats. The rats in the exercise groups were forced to run on a treadmill for 10 min, 30 min, and 60 min once a day for 28 consecutive days. ADHD rats displayed impairment of spatial learning ability, in contrast treadmill exercise ameliorated impairment of spatial learning ability. Treadmill exercise for 30 min per day showed most potent ameliorating effect on impairment of spatial learning ability. BDNF and TrkB expressions in the hippocampus were decreased in the ADHD rats, in contrast treadmill exercise enhanced BDNF and TrkB expressions. Treadmill exercise for 30 min and for 60 min per day showed enhancing effects on BDNF and TrkB expressions. Treadmill exercise alleviated deficits in the spatial learning ability through enhancing BDNF and TrkB expressions in the ADHD rats. Treadmill exercise for 30 min per day can be considered as the most effective therapeutic modality for the ADHD symptoms.

A longitudinal study of neuropsychological functioning and academic achievement in children with and without signs of attention-deficit/hyperactivity disorder

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) in childhood is associated with poor academic functioning. Deficits in academic functioning have proven to be less responsive to intervention than behavioral deficits in this population, yet the causes of this academic underperformance are not well understood. The purpose of this study is to examine the relationship between ADHD and academic performance in elementary-aged children in a developmental context. To do this, we study important cognitive variables and academic achievement over a three-year timeframe.

METHOD

Based on teacher ratings of ADHD, children were divided into a high symptom group (n = 17) and a low symptom group (n = 34). A thorough battery of cognitive and academic tests was administered at Time 1 and again 2 years later. Cognitive measures focused specifically on working memory and response inhibition.

RESULTS

RESULTS indicate that children who have high levels of ADHD signs differ from their low-sign peers in academic achievement and in several cognitive domains. Differences in cognitive functioning show a developmental trend consistent with earlier developmental delays in response inhibition and later delays in working memory. Working memory appears to be particularly important in several academic domains. Importantly, in a longitudinal model, working memory was more predictive of math achievement for students demonstrating signs of ADHD than for those who did not.

CONCLUSION

The relationship between these cognitive variables and academic functioning are explicated in the domains of reading, math, and problem solving.

Pathways to self-harmful behaviors in young women with and without ADHD: a longitudinal examination of mediating factors

BACKGROUND

Rates of suicide attempts and nonsuicidal self-injury [(NSSI); e.g., cutting, burning] peak in adolescence and early adulthood; females and individuals with psychiatric symptoms and diagnoses appear to beat particular risk. Hinshaw et al. [Journal of Consulting and Clinical Psychology, (2012), 80, 1041] reported that young women with histories of childhood ADHD diagnoses reported higher rates of suicide attempts and NSSI than nondiagnosed, comparison women.

METHODS

Via analyses of an ongoing longitudinal investigation, our aims are to examine, with respect to both aspects of self-harmful behavior, (a) ADHD subtype differences and effects of diagnostic persistence (vs. transient and nondiagnosed classifications) and (b) potential mediating effects of impulsivity and comorbid psychopathology, ascertained during adolescence.

RESULTS

Young adult women with a childhood diagnosis of ADHD-Combined type were at highest risk for suicide attempts as well as the most varied and severe forms of NSSI compared with those with ADHD-Inattentive type and those in the comparison group; participants with a persistent ADHD diagnosis were at higher risk than those with a transient diagnosis or those never meeting criteria for ADHD. Mediator analyses revealed that, during adolescence, an objective measure of impulsivity plus comorbid externalizing symptoms were simultaneous, partial mediators of the childhood ADHD-young adult NSSI linkage.Adolescent internalizing symptoms emerged as a partial mediator of the childhood ADHD-young adult suicide attempt linkage. CONCLUSIONs: ADHD in females, especially when featuring childhood impulsivity and especially with persistent symptomatology, carries high risk for self-harm. Psychiatric comorbidity and response inhibition are important mediators of this clinically important longitudinal association. We discuss limitations and implications for prevention and intervention.

Impact of executive functions on school and peer functions in youths with ADHD

Youths with attention-deficit/hyperactivity disorder (ADHD) are more likely to have social dysfunction at school. The authors explored the role of key executive functions (EF, i.e., spatial working memory and spatial planning) on school and peer functions in 511 youths with persistent ADHD according to the DSM-IV diagnostic criteria and 124 non-ADHD controls without any EF deficits. All the participants were assessed by a semi-structured psychiatric interview to confirm their previous and current diagnosis of ADHD and other psychiatric disorders and by the Spatial Working Memory (SWM) and Stocking of Cambridge (SOC) tasks. The participants and their parents reported the participants' school functions and peer relationships. There were three ADHD subgroups: (1) ADHD with deficits in both SWM and SOC tasks (n=121); (2) ADHD with deficit in either SWM or SOC task (n=185); (3) ADHD without deficits in SWM or SOC task (n=205). All the three ADHD groups, regardless of EF deficits, had lower school grade, poorer attitude toward school work, poorer school interactions, more behavioral problems at school, and more severe problems in peer relationships than non-ADHD controls. Multivariate analyses revealed positive associations between deficit in the SWM task and school and peer dysfunctions, and between deficits in the SOC task and impaired peer interactions. Older age and psychiatric comorbidity also contributed to increased risk of school and peer dysfunctions. Our findings suggest that deficits in EF, such as spatial working memory and planning, might be associated with school and peer dysfunctions.

The impact of depressive symptoms in adults with ADHD symptoms on family function and ADHD symptoms of their children

OBJECTIVE

People with attention-deficit/hyperactivity disorder (ADHD) exhibit considerable impairment in social, academic, or occupational functioning. The present study aimed to examine the patterns of associations between ADHD symptoms, depression, and family functioning.

METHODS

The sample consisted of 1,022 adults randomly selected from a district in Seoul, South Korea. Several self-assessment scales were utilized to rate ADHD symptoms (both past and current), current symptoms of depression, and level of family functioning. ADHD symptoms in the children of these participants were also assessed. Pearson's correlation and multiple linear regression analyses were performed; structural equation modeling (SEM) was conducted to determine the best fitting model.

RESULTS

Adult ADHD symptoms were positively associated with depressive symptoms. Depressive symptoms, in turn, mediated the relationship between adult ADHD symptoms and cohesion among family members. In addition, depressive symptoms mediated the relationship between adult ADHD symptoms and their children's ADHD symptoms.

CONCLUSION

The relationship between adult ADHD symptoms and family dysfunction may be influenced by depressive symptoms. When treating ADHD in adults, clinicians should pay attention to the presence or absence of depression.

Functional connectivity of neural motor networks is disrupted in children with developmental coordination disorder and attention-deficit/hyperactivity disorder

Developmental coordination disorder (DCD) and attention deficit/hyperactivity disorder (ADHD) are prevalent childhood disorders that frequently co-occur. Evidence from neuroimaging research suggests that children with these disorders exhibit disruptions in motor circuitry, which could account for the high rate of co-occurrence. The primary objective of this study was to investigate the functional connections of the motor network in children with DCD and/or ADHD compared to typically developing controls, with the aim of identifying common neurophysiological substrates. Resting-state fMRI was performed on seven children with DCD, 21 with ADHD, 18 with DCD + ADHD and 23 controls. Resting-state connectivity of the primary motor cortex was compared between each group and controls, using age as a co-factor. Relative to controls, children with DCD and/or ADHD exhibited similar reductions in functional connectivity between the primary motor cortex and the bilateral inferior frontal gyri, right supramarginal gyrus, angular gyri, insular cortices, amygdala, putamen, and pallidum. In addition, children with DCD and/or ADHD exhibited different age-related patterns of connectivity, compared to controls. These findings suggest that children with DCD and/or ADHD exhibit disruptions in motor circuitry, which may contribute to problems with motor functioning and attention. Our results support the existence of common neurophysiological substrates underlying both motor and attention problems.

Neurotrophin 3 genotype and emotional adverse effects of osmotic-release oral system methylphenidate (OROS-MPH) in children with attention-deficit/hyperactivity disorder

Neurotrophin 3 (NTF3) has been studied in relation to the pathophysiology of attention-deficit/hyperactivity disorder (ADHD) and mood disorders as well as psychostimulant action. We hypothesized that the risk of an emotional side effect to methylphenidate (MPH) treatment may be associated with NTF3 genotypes. Ninety-six medication-naïve children with ADHD (mean age 8.70, standard deviation 1.41 years, 79 males) were genotyped and treated with MPH. At baseline, which was prior to MPH treatment, and after two weeks of medication, investigators asked children and their parents or caregivers about adverse events using a symptom rating scale. ADHD subjects with the A/A genotype at the NTF3 rs6332 polymorphism showed the highest 'Emotionality' and 'Over-focus/euphoria' factor scores, followed by those with the G/A genotype and those with the G/G genotype (p=0.042 and p=0.045, respectively). ADHD subjects with the A/A genotype at the NTF3 rs6332 polymorphism showed the highest 'Proneness to crying' and 'Nail biting' item scores, followed by those with the G/A genotype and those with the G/G genotype (p=0.047 and p=0.017, respectively). These data provide preliminary evidence that genetic variation in the NTF3 gene is related to susceptibility to emotional side effects in response to MPH treatment in Korean children with ADHD.

Preclinical pharmacokinetics, pharmacology and toxicology of lisdexamfetamine: a novel d-amphetamine pro-drug

Lisdexamfetamine dimesylate (LDX) is a novel pro-drug of d-amphetamine that is currently used for the treatment of attention-deficit/hyperactivity disorder in children aged ≥ 6 years and adults. LDX is enzymatically cleaved to form d-amphetamine following contact with red blood cells, which reduces the rate of appearance and magnitude of d-amphetamine concentration in the blood and hence the brain when compared with immediate-release d-amphetamine at equimolar doses. Thus, the increase of striatal dopamine efflux and subsequent increase of locomotor activity following d-amphetamine is less prominent and slower to attain maximal effect following an equimolar dose of LDX. Furthermore, unlike d-amphetamine, the pharmacodynamic effects of LDX are independent of the route of administration underlining the requirement to be hydrolyzed by contact with red blood cells. It is conceivable that these pharmacokinetic and pharmacodynamic differences may impact the psychostimulant properties of LDX in the clinic. This article reviews the preclinical pharmacokinetics, pharmacology, and toxicology of LDX. This article is part of the Special Issue entitled 'CNS Stimulants'.

Substance use disorders in association with attention-deficit/hyperactivity disorder, co-morbid mental disorders, and medication in a nationwide sample

BACKGROUND

The association of substance use disorders (SUD) with attention-deficit disorder (ADHD), co-morbid mental disorders, and medication has only been studied in isolation and in rather small samples.

PROCEDURE

Data were based on four Danish national registers covering a total of 20,742 patients with ADHD, their dispensed medications, co-morbid mental disorders, and associated SUD between 1994 and 2010. The analyses considered the risk of various medications (methylphenidate only, antidepressants only, antipsychotic only, mixed medication) in comparison to a control group of non-medicated patients with ADHD, various co-morbid disorders, duration of medication, age at diagnosis, year of birth, and sex for developing SUD.

RESULTS

The observation period of the cohort ranged between 2.25 and 66.21 years and the prevalence for SUD was 9.51%. The SUD rates were significantly higher prior to, compared to following the onset of medication in the methylphenidate and the mixed medication subgroup, whereas they were significantly higher following onset of medication in the antidepressants and the antipsychotics subgroups. However, the SUD rates were significantly higher in all drug conditions except for methylphenidate after onset of medication compared to the non-medicated subgroup. Risk factors obtained by regression analysis did not include methylphenidate but did include antidepressants, antipsychotics, and mixed medications, in combination with co-morbid mood, anxiety, personality, and conduct disorders, and older age at diagnosis. Longer duration of medication and female sex were protective factors.

CONCLUSIONS

This representative study based on a large nationwide psychiatric sample provides solid evidence into the patterns of SUD in patients with ADHD based on medication use and co-morbidities.

Gamma aminobutyric acidergic and neuronal structural markers in the nucleus accumbens core underlie trait-like impulsive behavior

BACKGROUND

Pathological forms of impulsivity are manifest in a number of psychiatric disorders listed in DSM-5, including attention-deficit/hyperactivity disorder and substance use disorder. However, the molecular and cellular substrates of impulsivity are poorly understood. Here, we investigated a specific form of motor impulsivity in rats, namely premature responding, on a five-choice serial reaction time task.

METHODS

We used in vivo voxel-based magnetic resonance imaging and ex vivo Western blot analyses to investigate putative structural, neuronal, and glial protein markers in low-impulsive (LI) and high-impulsive rats. We also investigated whether messenger RNA interference targeting glutamate decarboxylase 65/67 (GAD65/67) gene expression in the nucleus accumbens core (NAcbC) is sufficient to increase impulsivity in LI rats.

RESULTS

We identified structural and molecular abnormalities in the NAcbC associated with motor impulsivity in rats. We report a reduction in gray matter density in the left NAcbC of high-impulsive rats, with corresponding reductions in this region of glutamate decarboxylase (GAD65/67) and markers of dendritic spines and microtubules. We further demonstrate that the experimental reduction of de novo of GAD65/67 expression bilaterally in the NAcbC is sufficient to increase impulsivity in LI rats.

CONCLUSIONS

These results reveal a novel mechanism of impulsivity in rats involving gamma aminobutyric acidergic and structural abnormalities in the NAcbC with potential relevance to the etiology and treatment of attention-deficit/hyperactivity disorder and related disorders.

ADHD, stimulant treatment in childhood and subsequent substance abuse in adulthood - a naturalistic long-term follow-up study

The purpose of the study was to estimate the risk of substance use disorder (SUD) and alcohol abuse in adulthood among children and adolescents with attention-deficit hyperactivity disorder (ADHD) compared to the background population. Furthermore, to examine whether the age at initiation and duration of stimulant treatment in childhood predicts SUD and alcohol abuse in adulthood. 208 youths with ADHD (183 boys; 25 girls) were followed prospectively. Diagnoses of SUD and alcohol abuse were obtained from The Danish Psychiatric Central Register. The relative risk (RR) of SUD and alcohol abuse for cases with ADHD, compared to the background population was 7.7 (4.3-13.9) and 5.2 (2.9-9.4), respectively. Female gender, conduct disorder in childhood and older age at initiation of stimulant treatment increased the risk of later SUD and alcohol abuse. Our results warrant increased focus on the possibly increased risk of substance abuse in females with ADHD compared to males with ADHD.

Pragmatic deficits and social impairment in children with ADHD

BACKGROUND

Impaired social functioning has been well documented in individuals with attention-deficit/hyperactivity disorder (ADHD). Existing treatments for ADHD are effective for managing core symptoms, but have limited effectiveness at improving social skills, suggesting that social deficits in ADHD may not be directly related to core symptoms of the disorder. Language problems are also common in ADHD, with accumulating evidence of pragmatic language difficulties. Pragmatic deficits are associated with social impairment in several neurodevelopmental disorders. This study systematically examined pragmatic language functioning in children with ADHD and whether social impairment in ADHD is mediated by pragmatic deficits.

METHOD

Sixty-three children (28 ADHD; 35 typically developing), ages 7-11 years, underwent a comprehensive assessment of pragmatic language, including parent ratings, standardized tests, and a narrative task. Parents also rated children's social skills on the Social Skills Improvement System.

RESULTS

Children with ADHD had poorer pragmatic language skills relative to peers across all measures, even after controlling for general language abilities. Furthermore, pragmatic abilities as measured by parent ratings, mediated the relation between ADHD and social skills.

CONCLUSIONS

Pragmatic language skills are impaired in many children with ADHD and may partially account for high rates of social impairment. Implications for treatment and possible prevention of social problems in children with ADHD are discussed.

Executive functions in borderline personality disorder

Different domains of executive function such as working memory and response inhibition were investigated together with elementary cognitive processes in borderline personality disorder (BPD). Patients with BPD (N=28) were compared to nonpatient controls (NP, N=28) on eight tasks (e.g. n-back, Go/NoGo, CPT-AX). In order to separate impairments in different cognitive domains and to assess the influence of more elementary cognitive processes on executive functioning, tasks were embedded in a reaction-time-decomposition approach. BPD patients solved tasks with accuracies comparable to those of nonpatients. The only exception was the n-back task, for which working memory is required: here, error rates were higher and increased more prominently in BPD patients depending on working memory load. In most tasks, movement times were shorter for BPD patients than for nonpatients, while the quality of task-solving was comparable. The faster processing in the BPD group was observable starting with the simplest task, i.e. a simple reaction-time task. These findings suggest that domains of executive functioning are differentially affected in BPD. In contrast to load-dependent deficits in working memory, response inhibition processes were unimpaired. Faster action-related processes could be observed in BPD patients in a variety of tasks; however, these did not influence executive functioning.

Asthma and attention-deficit/hyperactivity disorder: a nationwide population-based prospective cohort study

BACKGROUND

Previous cross-sectional studies have suggested an association between asthma and attention-deficit/hyperactivity disorder (ADHD), but the temporal relationship was not determined. Using a nationwide population-based prospective case-control cohort study (1:4, age-/gender-matched), we hypothesized that asthma in infanthood or early childhood would increase the risk of ADHD in later life.

METHODS

In all, 2,294 children with asthma and 9,176 controls aged between 0 and 3 years in 2000 were included in our study. Cases of ADHD that occurred to the end of follow-up (31 December 2010) were identified.

RESULTS

Children with asthma had a higher incidence of developing ADHD (7% vs. 4.6%, p < .001) than control cohort during the follow-up period. After adjusting for age at enrollment, gender, level of urbanization, and comorbid allergic diseases (allergic rhinitis and atopic dermatitis), children with asthma had an elevated risk (HR: 1.31, 95% CI: 1.07-1.59) of developing ADHD compared with control group.

DISCUSSION

Our prospective study supported a temporal relationship between asthma and ADHD. Asthma in very early life increased the risk of developing ADHD during the school years. Further studies are required to investigate whether the prompt treatment of asthma and comorbid allergic diseases could prevent the development of ADHD or decrease ADHD symptoms.

Evidence for reduced tonic levels of GABA in the hippocampus of an animal model of ADHD, the spontaneously hypertensive rat

Recent studies have investigated the role of γ-aminobutyric acid (GABA) in the behavioural symptoms of attention-deficit/hyperactivity disorder (ADHD), specifically in behavioural disinhibition. Spontaneously hypertensive rats (SHR) are widely accepted as an animal model of ADHD, displaying core symptoms of the disorder. Using an in vitro superfusion technique, we have shown that glutamate-stimulated release of radio-actively labelled norepinephrine ([(3)H]NE) from prefrontal cortex and hippocampal slices is greater in SHR than in their normotensive control strain, Wistar-Kyoto rats (WKY), and/or a standard control strain, Sprague-Dawley rats (SD). In the present study, we investigated how the level of extracellular (tonic) GABA affects release of [(3)H]NE in hippocampal slices of male and female SHR, WKY and SD rats, in response to 3 glutamate stimulations (S1, S2, and S3). The hippocampal slices were prelabelled with [(3)H]NE and superfused with buffer containing 0μM, 1μM, 10μM, or 100μM GABA. Three consecutive glutamate stimulations were achieved by exposing slices to 3 pulses of glutamate (1mM), each separated by 10min. Increasing tonic levels of GABA increased basal and stimulated release of [(3)H]NE in all strains. When GABA was omitted from the superfusion buffer used to perfuse SHR hippocampal slices, but present at 100µM in the buffer used to perfuse WKY and SD hippocampal slices, glutamate-stimulated release of [(3)H]NE was similar in all three strains. In these conditions, the decrease in [(3)H]NE release from S1 to S2 and S3 was also similar in all three strains. These findings suggest that extracellular concentrations of GABA may be reduced in SHR hippocampus, in vivo, compared to WKY and SD. An underlying defect in GABA function may be at the root of the dysfunction in catecholamine transmission noted in SHR, and may underlie their ADHD-like behaviours.

Neurofunctional effects of methylphenidate and atomoxetine in boys with attention-deficit/hyperactivity disorder during time discrimination

BACKGROUND

The catecholamine agonists methylphenidate and atomoxetine effectively treat attention-deficit/hyperactivity disorder (ADHD). Furthermore, dopamine agonists have shown to improve time estimation in ADHD, a core cognitive deficit. However, few have compared the effects of methylphenidate and atomoxetine on brain function in ADHD, and none during time estimation. Using single dose challenges, we investigated shared and drug-specific effects in ADHD adolescents on the neural substrates of time discrimination (TD).

METHODS

Twenty ADHD adolescent male subjects were compared in a randomized double-blind cross-over design after single doses of methylphenidate, atomoxetine, and placebo in functional magnetic resonance imaging during TD. Normalization effects were assessed by comparing brain activation under each drug condition with that of 20 healthy age-matched control subjects.

RESULTS

Relative to control subjects, patients under placebo showed TD deficits and reduced activation of ventrolateral prefrontal cortex (VLPFC)/insula, inferior frontal cortex, and supplementary motor area. Performance differences were normalized only by methylphenidate, relative to both atomoxetine and placebo. Both medications, however, significantly upregulated right VLPFC/insula activation within patients and normalized its underactivation in ADHD boys under placebo relative to control subjects. The supplementary motor area and inferior frontal cortex activation differences that were observed under placebo were reduced by methylphenidate and atomoxetine, respectively, but neither survived rigorous testing for normalization.

CONCLUSIONS

While only methylphenidate had a drug-specific effect of improving TD performance deficits, both drugs significantly upregulated and normalized right VLPFC underactivation in ADHD boys under placebo relative to control subjects, suggesting shared effects of stimulants and nonstimulants on a key prefrontal dysfunction during timing.

Neural mechanisms of attention-deficit/hyperactivity disorder symptoms are stratified by MAOA genotype

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is characterized by deficits in reward sensitivity and response inhibition. The relative contribution of these frontostriatal mechanisms to ADHD symptoms and their genetic determinants is largely unexplored.

METHODS

Using functional magnetic resonance imaging and genetic analysis of the monoamine oxidase A (MAOA) gene, we investigated how striatal and inferior frontal activation patterns contribute to ADHD symptoms depending on MAOA genotype in a sample of adolescent boys (n = 190).

RESULTS

We demonstrate an association of ADHD symptoms with distinct blood oxygen level-dependent (BOLD) responses depending on MAOA genotype. In A hemizygotes of the expression single nucleotide polymorphism rs12843268, which express lower levels of MAOA, ADHD symptoms are associated with lower ventral striatal BOLD response during the monetary incentive delay task and lower inferior frontal gyrus BOLD response during the stop signal task. In G hemizygotes, ADHD symptoms are associated with increased inferior frontal gyrus BOLD response during the stop signal task in the presence of increased ventral striatal BOLD response during the monetary incentive delay task.

CONCLUSIONS

Depending on MAOA genotype, ADHD symptoms in adolescent boys are associated with either reward deficiency or insufficient response inhibition. Apart from its mechanistic interest, our finding may aid in developing pharmacogenetic markers for ADHD.

Low incidence of pathology detection and high cost of screening in the evaluation of asymptomatic short children

OBJECTIVE

To determine the incidence of pathology during routine screening of healthy short children, testing adherence to a consensus statement on the diagnosis and treatment of children with idiopathic short stature, and the cost per identified diagnosis resulting from comprehensive screening.

STUDY DESIGN

Retrospective chart review of 1373 consecutive short stature referrals evaluated at the Cincinnati Children's Hospital Medical Center Pediatric Endocrinology Clinic between 2008 and 2011. We identified 235 patients with a height of <3rd percentile, negative history and review of systems, and normal physical examination. Outcome measures were incidence of pathology detection, diagnostic group characteristics, clinicians' adherence to testing guidelines, and screening costs. ANOVA and χ(2) were used to analyze the data.

RESULTS

Nearly 99% of patients were diagnosed as possible variants of normal growth: 23% with familial short stature, 41% with constitutional delay of growth and maturation, and 36% with idiopathic short stature. The incidence of newly diagnosed pathology was 1.3%: 1 patient with biopsy-proved celiac disease, 1 with unconfirmed celiac disease, and 1 with potential insulin-like growth factor I receptor defect. On average, each patient had 64.3% of the recommended tests for age and sex; 2.1% of patients had all of the recommended testing. The total screening tests costs were $315321, yielding $105107 per new diagnosis entertained.

CONCLUSIONS

Healthy short children do not warrant nondirected, comprehensive screening. Future guidelines for evaluating short stature should include patient-specific testing.

Executive functions in girls with and without childhood ADHD: developmental trajectories and associations with symptom change

BACKGROUND

We prospectively followed an ethnically and socioeconomically diverse sample of girls with attention-deficit/hyperactivity disorder (ADHD) (n = 140) and a matched comparison sample (n = 88) from childhood through young adulthood to evaluate developmental trajectories of executive functions (EF) and associations between EF trajectories and dimensional measures of ADHD symptoms. We hypothesized that (a) EF trajectories would be similar in girls both with and without childhood ADHD, with the ADHD group showing greater impairment across time; and (b) changes in EF abilities would predict changes in ADHD symptoms across time, consistent with the theory that ADHD symptom reductions partially result from prefrontally mediated EF development.

METHOD

Latent growth curve models were used to evaluate development of sustained attention, response inhibition, working memory, and global EF abilities, and associations between EF trajectories and ADHD symptom trajectories.

RESULTS

Girls with childhood-diagnosed ADHD showed greater improvement across development on measures of sustained attention and global EF, but similar rates of improvement on measures of working memory and response inhibition. Changes in the global EF measure predicted changes in both inattentive and hyperactive-impulsive symptoms across time, whereas changes in response inhibition predicted changes in hyperactive-impulsive symptoms; associations between changes in other EF variables and symptoms were not significant.

CONCLUSIONS

Findings suggest variability in patterns of EF improvement over time in females with ADHD histories and indicate that EF development may play a role in symptom change.