Clinical Diagnosis Of Attention Deficit Hyperactivity Disorder Research Articles

Discovery of the first genome-wide significant risk loci for attention deficit/hyperactivity disorder.

Attention deficit/hyperactivity disorder (ADHD) is a highly heritable childhood behavioral disorder affecting 5% of children and 2.5% of adults. Common genetic variants contribute substantially to ADHD susceptibility, but no variants have been robustly associated with ADHD. We report a genome-wide association meta-analysis of 20,183 individuals diagnosed with ADHD and 35,191 controls that identifies variants surpassing genome-wide significance in 12 independent loci, finding important new information about the underlying biology of ADHD. Associations are enriched in evolutionarily constrained genomic regions and loss-of-function intolerant genes and around brain-expressed regulatory marks. Analyses of three replication studies: a cohort of individuals diagnosed with ADHD, a self-reported ADHD sample and a meta-analysis of quantitative measures of ADHD symptoms in the population, support these findings while highlighting study-specific differences on genetic overlap with educational attainment. Strong concordance with GWAS of quantitative population measures of ADHD symptoms supports that clinical diagnosis of ADHD is an extreme expression of continuous heritable traits.

Do borderline personality disorder and attention-deficit/hyperactivity disorder co-aggregate in families? A population-based study of 2 million Swedes

Large-scale family studies on the co-occurrence of attention-deficit/hyperactivity disorder (ADHD) and borderline personality disorder (BPD) are lacking. Thus, we aimed to estimate the co-occurrence and familial co-aggregation of clinically ascertained ADHD and BPD diagnoses using the entire Swedish population. In a register-based cohort design we included individuals born in Sweden 1979–2001, and identified their diagnoses during 1997–2013; in total, 2,113,902 individuals were included in the analyses. We obtained clinical diagnoses of ADHD and BPD from inpatient and outpatient care. Individuals with an ADHD diagnosis had an adjusted (for birth year, sex, and birth order) odds ratio (aOR) of 19.4 (95% confidence interval [95% CI] = 18.6–20.4) of also having a BPD diagnosis, compared to individuals not diagnosed with ADHD. Having a sibling with ADHD also increased the risk for BPD (monozygotic twins, aOR = 11.2, 95% CI = 3.0–42.2; full siblings, aOR = 2.8, 95% CI = 2.6–3.1; maternal half-siblings, aOR = 1.4, 95% CI = 1.2–1.7; paternal half-siblings, aOR = 1.5, 95% CI = 1.3–1.7). Cousins also had an increased risk. The strength of the association between ADHD and BPD was similar in females and males, and full siblings showed similar increased risks regardless of sex. Among both males and females, ADHD and BPD co-occur within individuals and co-aggregate in relatives; the pattern suggests shared genetic factors and no robust evidence for etiologic sex differences was found. Clinicians should be aware of increased risks for BPD in individuals with ADHD and their relatives, and vice versa.

Health-related quality of life and burden of illness in adults with newly diagnosed attention-deficit/hyperactivity disorder in Sweden

BackgroundThis observational, cross-sectional, retrospective chart review aimed to identify factors determining health-related quality of life (HRQoL) in adults with newly diagnosed attention-deficit/hyperactivity disorder (ADHD) in Sweden.MethodsAdult participants with a new clinical diagnosis of ADHD were enrolled from two specialist outpatient clinics in Stockholm, Sweden, from 2013 to 2015. Data extracted from patient records included demographics, clinical characteristics and comorbid psychiatric diagnoses identified using the Mini International Neuropsychiatric Interview (MINI). Depression severity was assessed using the Montgomery–Åsberg Depression Rating Scale – Self-reported (MADRS-S). The self-rated five-dimension EuroQol questionnaire (EQ-5D) was used to measure HRQoL. Predictors of EQ-5D index score were identified using multivariate linear regression adjusting for age, sex, education level, and main income source.ResultsThe mean age of the 189 enrolled patients was 35.2 years (standard deviation [SD], 12.3), and 107 (57%) were female. Psychiatric comorbidities were present in 92 patients (49%), with anxiety and depression being the most common diagnoses. The mean EQ-5D index score was 0.63 (SD, 0.28). Low EQ-5D index scores were significantly associated with high MADRS-S scores, multiple comorbid psychiatric disorders, low educational achievement, female sex, and not having a main income derived from employment or self-employment.ConclusionsThese findings suggest that adults with newly diagnosed ADHD experience low HRQoL, which may often be exacerbated by psychiatric comorbidities such as anxiety and depression. Patients presenting with ADHD and psychiatric comorbidities in adulthood may require particular care and resources in the management of their ADHD.

Resting-State Brain Signal Variability in Prefrontal Cortex Is Associated With ADHD Symptom Severity in Children.

Atypical brain function in attention-deficit/hyperactivity disorder (ADHD) has been identified using both task-activation and functional connectivity fMRI approaches. Recent work highlights the potential for another measure derived from functional neuroimaging data, brain signal variability, to reveal insights into clinical conditions. Higher brain signal variability has previously been linked with optimal behavioral performance. At present, little is known regarding the relationship between resting-state brain signal variability and ADHD symptom severity. The current study examined the relationship between a measure of moment-to-moment brain signal variability called mean-square successive difference (MSSD) and ADHD symptomatology in a group of children (7–12 years old) with (n = 40) and without (n = 30) a formal diagnosis of ADHD. A categorical analysis comparing subjects with and without a clinical diagnosis of ADHD showed no differences in MSSD between groups. A dimensional analysis revealed a positive relationship between MSSD and overall ADHD symptom severity and inattention across children with and without an ADHD diagnosis. Specifically, this positive relationship was found in medial prefrontal areas comprising the default mode network. These results demonstrate a link between intrinsic brain signal variability and ADHD symptom severity that cuts across diagnostic categories, and point to a locus of dysfunction consistent with previous neuroimaging literature.

Increased attention-deficit/hyperactivity symptoms in atopic dermatitis are associated with history of antihistamine use.

Epidemiologic evidence indicates a relevant association between atopic dermatitis (AD) and attention-deficit/hyperactivity disorder (ADHD). Underlying mechanisms and ways to best identify subgroups of AD patients at risk for ADHD are poorly understood. To compare sociodemographic, clinical and psychosocial characteristics of children with AD, ADHD, comorbid AD/ADHD and age-matched healthy controls and to investigate aspects of AD related to ADHD symptoms. Applying a factorial design, we investigated 4 groups of children aged 6-12years: AD-only (ie, without ADHD), ADHD-only (ie, without AD), AD+ADHD and healthy controls (HC; ie, no AD/no ADHD). Using validated instruments, ADHD symptoms and other behavioural problems, quality of life, parenting stress and sleeping problems were compared between groups. In children with AD-only, clinical signs (objective SCORAD), symptoms (POEM, VAS pruritus, VAS sleeping problems) and previous treatment of AD were assessed to investigate disease patterns related to ADHD symptoms. Compared to HC (n=47), children with AD-only (n=42), ADHD-only (n=34) and comorbid AD+ADHD (n=31) had significantly increased behavioural problems and decreased quality of life. Children with AD-only had significantly higher levels of ADHD symptoms than HC. In children with AD-only, previous use of antihistamines was significantly associated with increased ADHD symptoms (OR 1.88; 95% CI 1.04-3.39). Current clinical signs and AD symptoms were unrelated to the level of ADHD symptoms. Even if the clinical diagnosis of ADHD is excluded, children with AD show increased levels of ADHD symptoms. Further investigations need to determine whether early antihistamine exposure is a major risk factor for ADHD or a surrogate for previous AD severity and/or associated sleeping problems.

Relative age within the school year and diagnosis of attention-deficit hyperactivity disorder: a nationwide population-based study

Findings are mixed on the relationship between attention-deficit hyperactivity disorder (ADHD) and younger relative age in the school year. We aimed to investigate whether relative age is associated with ADHD diagnosis in a country where prescribing rates are low and whether any such association has changed over time or relates to comorbid disorders (eg, conduct disorder [CD], oppositional defiant disorder [ODD], or learning disorder [LD]). We used nationwide population-based registers to identify all Finnish children born between Jan 1, 1991, and Dec 31, 2004, who were diagnosed with ADHD from age 7 years onwards (age of starting school). We calculated incidence ratios to assess the inter-relations between relative age within the school year, age at ADHD diagnosis, and year of diagnosis (1998-2003 vs 2004-11). Between Jan 1, 1998, and Dec 31, 2011, 6136 children with ADHD were identified. Compared with the oldest children in the school year (ie, those born between January and April), the cumulative incidence of an ADHD diagnosis was greatest for the youngest children (ie, those born between September and December); for boys the incidence ratio was 1·26 (95% CI 1·18-1·35; p<0·0001) and for girls it was 1·31 (1·12-1·54; p=0·0007). The association between relative age and age at ADHD diagnosis reflected children diagnosed before age 10 years, and the strength of this association increased during recent years (2004-11). Thus, compared with children born between January and April, for those born between May and August, the ADHD incidence ratio was 1·37 (95% CI 1·24-1·53; p<0·0001) and for those born between September and December, the incidence ratio was 1·64 (1·48-1·81; p<0·0001). The relative age effect was not accounted for by comorbid disorders such as CD, ODD, or LD. In a health service system with low prescribing rates for ADHD, a younger relative age is associated with an increased likelihood of receiving a clinical diagnosis of ADHD. This effect has increased in recent years. Teachers, parents, and clinicians should take relative age into account when considering the possibility of ADHD in a child or encountering a child with a pre-existing diagnosis. Academy of Finland, Finnish Medical Foundation, Orion Pharma Foundation, Finnish Cultural Foundation.

Maternal body mass index before pregnancy as a risk factor for ADHD and autism in children.

The risk of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorders (ASD) may be influenced by environmental factors such as maternal obesity before pregnancy. Previous studies investigating those associations have found divergent results. We aim to investigate in a large birth cohort this association further in children with ADHD, ASD and comorbid ADHD and ASD. Our study population consisted of 81,892 mother-child pairs participating in the Danish National Birth Cohort (DNBC). Information about pre-pregnancy weight and height was collected in week 16 of pregnancy; the analysis was divided into groups based on BMI. Children with a clinical diagnosis of ADHD and/or ASD were identified in the Danish health registries at an average age of 13.3years. Hazard ratios (HRs) were estimated using time-to-event analysis. Compared to normal weight mothers, the risk of having a child with ADHD was significantly increased if the mother was overweight (HR=1.28 [95% CI 1.15;1.48]), obese (HR=1.47 [95% CI 1.26;1.71]) or severely obese (HR=1.95 [95% CI 1.58;2.40]). The same pattern was seen for the combined ADHD and ASD group. Regarding ASD, an increased risk was observed in underweight (HR=1.30 [95% CI 1.01;1.69]) and obese (HR=1.39 [95% CI 1.11;1.75]) mothers. Subgroup analysis revealed that the association in the ADHD group could mostly be attributable to the hyperactive group. Maternal obesity before pregnancy is a risk factor for ADHD in children. Maternal obesity as well as underweight may also be associated with an increased risk for ASD.

RANZCP 2017 Book of Abstracts

Background: Attention-deficit hyperactivity disorder (ADHD) is one of the most common mental health disorders in children. Limitations of behavioural interventions and pharmacological treatment have led to the development of other novel interventions. Neurofeedback has shown promise in improving not only inattention symptoms but also impulsivity/hyperactivity symptoms. A feed-forward mechanism has been proposed to be more feasible in the treatment of ADHD as it trains individuals to harness their ability to pay attention and also shows promise in improving impulsivity symptoms. Objectives: The aim of the current study is to investigate the impact of a novel intervention using (feed-forward) brain-to-computer interface (BCI) technology on an objective measure of attention and impulsivity in children with ADHD. Methods: A total of 172 children aged 6 to 12 years (mean = 8.63, standard deviation = 1.51) with a clinical diagnosis of ADHD, inattentive or combined subtype were recruited. Participants were randomized into the waitlist-control or intervention group. Participants in the intervention group underwent 24 sessions of brain-to-computer interface technology (BCI) intervention over a period of 8 weeks, whereas participants in the control group did not receive any intervention. The Conners’ Continuous Performance Test, second edition (CPT-II) was administered to the participants before and after the treatment. Findings: Analysis was conducted for the intervention and control groups at weeks 1 and 8.Conclusions: Results will be discussed with a view to inform future research.

Maternal alcohol use during pregnancy and offspring attention-deficit hyperactivity disorder (ADHD): a prospective sibling control study.

Maternal alcohol use during pregnancy has repeatedly been associated with development of attention-deficit hyperactivity disorder (ADHD) in the offspring. It is, however not known whether this reflects a direct casual intra-uterine effect or a non-causal relationship due to confounding. We used three different approaches to control for measured and unmeasured confounding: statistical adjustment for covariates, negative control comparison against maternal pre-pregnancy alcohol use, and comparison among differentially exposed siblings. The sample comprised 114 247 children (34 283 siblings) from 94 907 mothers, recruited to the Norwegian Mother and Child Birth Cohort Study between 1999 and 2008. Self-reported measurements of alcohol use were obtained in week 30 during the pregnancy. Mothers rated offspring ADHD symptoms at 5 years on two measures. Clinical ADHD diagnoses were obtained from the Norwegian Patient Registry. We found an overall positive association between maternal alcohol use during pregnancy and offspring ADHD symptoms, which was only marginally attenuated after inclusion of measured covariates. Both the negative control and the sibling comparison analysis further attenuated the estimated association, but it remained greater than zero [β = 0.017, 95% confidence interval (CI) = 0.005-0.030). No association was found between maternal alcohol use during pregnancy and offspring ADHD diagnosis. For offspring ADHD symptoms we found a weak, but possibly causal association with maternal alcohol use during pregnancy, but no such effect was observed for clinical ADHD diagnosis.

NIRS-based neurofeedback training in a virtual reality classroom for children with attention-deficit/hyperactivity disorder: study protocol for a randomized controlled trial

BackgroundChildren with attention-deficit/hyperactivity disorder (ADHD) suffer from attention deficits, motor hyperactivity, and impulsive behaviour. These impairments are experienced at home, at school, and with friends. Functional imaging studies show that ADHD behaviour and impairments in executive functions (EFs) are mirrored by aberrant neurophysiological functioning. Moreover, several studies show that ADHD behaviour, impairments in EFs, and a lack of self-control contribute to poor school performance. Non-pharmacological interventions such as neurofeedback training (NFT), for instance, aim at improving neurophysiological and neuropsychological functioning as well as behaviour. Consequently, NFT is expected to improve school performance, EFs, and self-control in children with ADHD. Generalization of acquired self-regulation skills from laboratory to real life is crucial for a transfer to everyday situations and is hypothesized to be facilitated via training using virtual reality (VR) environments. Consequently, experiencing NFT in VR is expected to yield greater effects than training in two dimensions (2D).Methods/designNinety children with a clinical diagnosis of ADHD will be included in the study. Participants may be medicated or unmedicated. After random assignation to one of three conditions, all participants receive 15 training sessions of either near-infrared spectroscopy (NIRS)-based NFT in VR, NIRS-based NFT in 2D, or electromyogram-based biofeedback training in VR. ADHD symptoms, self-control, EF, health-related quality of life, school performance, and motor activity measured via parent, teacher, and child reports or objectively will be assessed before and after the intervention and at a 6 months follow-up. Furthermore, we are interested in parents’ expectations about the training’s effects.DiscussionThis is, to our knowledge, the first study investigating the efficacy of NFT for children with ADHD in a VR compared to a 2D environment. Furthermore, this study will contribute to the discussion about the efficacy and specific and unspecific effects of NFTs in children with ADHD. In addition to commonly assessed variables such as ADHD symptoms, NIRS and behavioural data obtained in EF measures, health-related quality of life, and parents’ expectations about the intervention’s effects, this study will investigate the effects on self-control, school performance, and motor activity.Trial registrationClinicalTrials.gov, NCT02572180. Registered on 19 November 2015.

Dificultades de reconocimiento emocional facial como déficit primario en niños con trastorno por déficit de atención/hiperactividad: revisión sistemática

It has recently been warned that children with attention deficit hyperactivity disorder (ADHD) show a deficit in emotional competence and emotional intelligence, specifically in their ability to emotional recognition. A systematic review of the scientific literature in reference to the emotional recognition of facial expressions in children with ADHD is presented in order to establish or rule the existence of emotional deficits as primary dysfunction in this disorder and, where appropriate, the effect size of the differences against normal development or neurotypical children. The results reveal the recent interest in the issue and the lack of information. Although there is no complete agreement, most of the studies show that emotional recognition of facial expressions is affected in children with ADHD, showing them significantly less accurate than children from control groups in recognizing emotions communicated through facial expressions. A part of these studies make comparisons on the recognition of different discrete emotions; having observed that children with ADHD tend to a greater difficulty recognizing negative emotions, especially anger, fear, and disgust. These results have direct implications for the educational and clinical diagnosis of ADHD; and for the educational intervention for children with ADHD, emotional education might entail an advantageous aid.

Que faire devant un enfant ronfleur et hyperactif ?

Attention deficit hyperactivity disorder (ADHD) is a common disorder, often associated with sleep disorders. Patients with primary sleep disorders often present hyperactivity and/or attention deficit symptoms. Indeed, obstructive sleep disorder breathing (snoring, hypoventilation disorder, and obstructive sleep apnea syndrome) with poor sleep quality can mimic ADHD in children. In this case, inattention and hyperactivity behavior are induced by sleep disorders but do not constitute a clinical diagnosis of ADHD. Therefore, it can sometimes be difficult for the clinician to distinguish between a diagnosis of ADHD with comorbid sleep disorder and a sleep disorder that mimics ADHD symptoms. The objective of this article is to review the relations between ADHD and obstructive sleep disorder breathing and propose a decision tree to help diagnosis.

Hacia un diagnóstico más objetivo del TDAH: el papel de la Vergencia Ocular

El Trastorno por Déficit de Atención con Hiperactividad (TDAH) es uno de los trastornos más comunes del neurodesarrollo. El diagnóstico actual se fundamenta en la presencia de síntomas de inatención, hiperactividad o impulsividad detectados a través de la anamnesis, la exploración, las entrevistas con padres y profesores y las escalas de evaluación de conducta observada. Además deben realizarse exploraciones médicas y psicopatológicas para excluir otras causas de los síntomas. El proceso es complejo y laborioso. Dada la importancia de una identificación adecuada de los casos para intervenir precozmente se sugiere la necesidad de mejorar los métodos de diagnóstico añadiendo pruebas objetivas o marcadores que permitan un mayor precisión. Se revisan distintas estrategias utilizadas hasta el momento concluyendo que por ahora, ningún método ha demostrado una sensibilidad y especificidad suficiente. Recientemente encontramos una relación entre la vergencia ocular y el nivel de atención en adultos y niños. Mostramos que durante la fijación de la mirada los estímulos visuales modulan el ángulo de vergencia debido a su capacidad para capturar la atención. En un primer estudio piloto la prueba de vergencia ocular permitió discriminar entre niños sanos y niños con TDAH con un elevado grado de precisión. Se presentan los resultados iniciales de un estudio de validación donde se compara los resultados de vergencia ocular efectuados de forma ciega a un grupo de niños sanos con un grupo de niños con TDAH y un grupo de niños con otros trastornos de atención o aprendizaje y mediante algoritmos basados en “machine learning” se obtiene un grado de discriminación del 96% entre sanos y TDAH y entre estos y el grupo de niños con otros problemas de atención o aprendizaje es de 85%. En conclusión, la evaluación de la Vergencia Ocular puede constituir una herramienta válida y objetiva de ayuda al diagnóstico clínco del TDAH.

FUNCIONES EJECUTIVAS Y MOTIVACIÓN DE NIÑOS CON TRASTORNO DE ESPECTRO AUTISTA (TEA) Y TRASTORNO POR DÉFICIT DE ATENCIÓN CON HIPERACTIVIDAD (TDAH)

Resumen Objetivos. Comparar el perfil de niños con trastorno del espectro autista (TEA) y niños con trastorno por déficit de atención con hiperactividad (TDAH), presentación combinada, en componentes del funcionamiento ejecutivo (FE) y en comportamientos que están asociados al aprendizaje. Método. Participaron en esta investigación 16 niños con un diagnóstico clínico de TDAH y 16 niños con un diagnóstico clínico de TEA con alto nivel de funcionamiento que habían sido diagnosticados en servicios de Neuropediatría de la Comunidad Valenciana. Las edades estaban comprendidas entre 7 y 11 años. El 94% eran varones y se encontraban escolarizados en aulas ordinarias, estando equiparados los dos grupos en edad y capacidad intelectual. Los profesores cumplimentaron el Inventario de funcionamiento ejecutivo (Behavior Rating Inventory of Executive Function; BRIEF; Gioia et al., 2000) que valora un espectro amplio de funciones ejecutivas y la escala de conductas de aprendizaje (Learning Behaviours Scale-LBS; McDermott et al., 2001) que aporta información sobre motivación, actitud hacia el aprendizaje, atención/persistencia y flexibilidad/estrategias de aprendizaje. Resultados. Los niños con TDAH presentaron significativamente más dificultades que los niños con TEA en memoria de trabajo y en planificación. Además, aunque ambos grupos experimentaron problemas que superan lo esperado, también los niños con TDAH estuvieron más afectados en los índices generales de FE, el índice metacognitivo y el de regulación comportamental. En la misma línea, en las conductas de aprendizaje, tampoco aparecieron diferencias significativas entre TEA y TDAH, si bien el porcentaje de casos afectados se situó en un nivel claramente superior en niños con TDAH a excepción del factor de flexibilidad/estrategia de aprendizaje. Conclusiones. Se comentan las implicaciones de los hallazgos para optimizar los procedimientos de enseñanza de niños con TEA y con TDAH. Palabras clave. Funcionamiento ejecutivo.Aprendizaje. Motivación. TEA. TDAH.

The Effectiveness of Parent Training as a Treatment for Preschool Attention-Deficit/Hyperactivity Disorder: Study Protocol for a Randomized Controlled, Multicenter Trial of the New Forest Parenting Program in Everyday Clinical Practice.

BackgroundParent training is recommended as the first-line treatment for attention-deficit/hyperactivity disorder (ADHD) in preschool children. The New Forest Parenting Programme (NFPP) is an evidence-based parenting program developed specifically to target preschool ADHD.ObjectiveThe objective of this trial is to investigate whether the NFPP can be effectively delivered for children referred through official community pathways in everyday clinical practice.MethodsA multicenter randomized controlled parallel arm trial design is employed. There are two treatment arms, NFPP and treatment as usual. NFPP consists of eight individually delivered parenting sessions, where the child attends during three of the sessions. Outcomes are examined at three time points (T1, T2, T3): T1 (baseline), T2 (week 12, post intervention), and T3 (6 month follow/up). 140 children between the ages of 3-7, with a clinical diagnosis of ADHD, informed by the Development and Well Being Assessment, and recruited from three child and adolescent psychiatry departments in Denmark will take part. Randomization is on a 1:1 basis, stratified for age and gender.ResultsThe primary endpoint is change in ADHD symptoms as measured by the Preschool ADHD-Rating Scale (ADHD-RS) by T2. Secondary outcome measures include: effects on this measure at T3 and T2 and T3 measures of teacher reported Preschool ADHD-RS scores, parent and teacher rated scores on the Strength & Difficulties Questionnaire, direct observation of ADHD behaviors during Child’s Solo Play, observation of parent-child interaction, parent sense of competence, and family stress. Results will be reported using the standards set out in the Consolidated Standards of Reporting Trials Statement for Randomized Controlled Trials of nonpharmacological treatments.ConclusionsThe trial will provide evidence as to whether NFPP is a more effective treatment for preschool ADHD than the treatment usually offered in everyday clinical practice.Trial RegistrationClinicalTrials.gov NCT01684644; https://clinicaltrials.gov/ct2/show/NCT01684644?term= NCT01684644&rank=1 (Archived by WebCite at http://www.webcitation/6eOOAe8Qe)

Prospective observational study protocol to investigate long-term adverse effects of methylphenidate in children and adolescents with ADHD: the Attention Deficit Hyperactivity Disorder Drugs Use Chronic Effects (ADDUCE) study

IntroductionMethylphenidate is the most frequently used medication for the treatment of attention-deficit/hyperactivity disorder (ADHD) in Europe. Following concerns about its safety, the European Commission called for research into the long-term...

Characterising resting-state functional connectivity in a large sample of adults with ADHD

Attention-deficit/hyperactivity disorder (ADHD) is a common childhood psychiatric disorder that often persists into adulthood. While several studies have identified altered functional connectivity in brain networks during rest in children with ADHD, few studies have been performed on adults with ADHD. Existing studies have generally investigated small samples. We therefore investigated aberrant functional connectivity in a large sample of adult patients with childhood-onset ADHD, using a data-driven, whole-brain approach. Adults with a clinical ADHD diagnosis (N=99) and healthy, adult comparison subjects (N=113) underwent a 9-minute resting-state fMRI session in a 1.5T MRI scanner. After elaborate preprocessing including a thorough head-motion correction procedure, group independent component analysis (ICA) was applied from which we identified six networks of interest: cerebellum, executive control, left and right frontoparietal and two default-mode networks. Participant-level network maps were obtained using dual-regression and tested for differences between patients with ADHD and controls using permutation testing. Patients showed significantly stronger connectivity in the anterior cingulate gyrus of the executive control network. Trends were also observed for stronger connectivity in the cerebellum network in ADHD patients compared to controls. However, there was considerable overlap in connectivity values between patients and controls, leading to relatively low effect sizes despite the large sample size. These effect sizes were slightly larger when testing for correlations between hyperactivity/impulsivity symptoms and connectivity strength in the executive control and cerebellum networks. This study provides important insights for studies on the neurobiology of adult ADHD; it shows that resting-state functional connectivity differences between adult patients and controls exist, but have smaller effect sizes than existing literature suggested.

Linkage and association analysis of ADHD endophenotypes in extended and multigenerational pedigrees from a genetic isolate.

Attention-deficit/hyperactivity disorder (ADHD) is a heritable, chronic, neurodevelopmental disorder with serious long-term repercussions. Despite being one of the most common cognitive disorders, the clinical diagnosis of ADHD is based on subjective assessments of perceived behaviors. Endophenotypes (neurobiological markers that cosegregate and are associated with an illness) are thought to provide a more powerful and objective framework for revealing the underlying neurobiology than syndromic psychiatric classification. Here, we present the results of applying genetic linkage and association analyses to neuropsychological endophenotypes using microsatellite and single nucleotide polymorphisms. We found several new genetic regions linked and/or associated with these endophenotypes, and others previously associated to ADHD, for example, loci harbored in the LPHN3, FGF1, POLR2A, CHRNA4 and ANKFY1 genes. These findings, when compared with those linked and/or associated to ADHD, suggest that these endophenotypes lie on shared pathways. The genetic information provided by this study offers a novel and complementary method of assessing the genetic causes underpinning the susceptibility to behavioral conditions and may offer new insights on the neurobiology of the disorder.

An objective measure of hyperactivity aspects with compressed webcam video.

BackgroundObjective measures of physical activity are currently not considered in clinical guidelines for the assessment of hyperactivity in the context of Attention-Deficit/Hyperactivity Disorder (ADHD) due to low and inconsistent associations between clinical ratings, missing age-related norm data and high technical requirements.MethodsThis pilot study introduces a new objective measure for physical activity using compressed webcam video footage, which should be less affected by age-related variables. A pre-test established a preliminary standard procedure for testing a clinical sample of 39 children aged 6–16 years (21 with a clinical ADHD diagnosis, 18 without). Subjects were filmed for 6 min while solving a standardized cognitive performance task. Our webcam video-based video-activity score was compared with respect to two independent video-based movement ratings by students, ratings of Inattentiveness, Hyperactivity and Impulsivity by clinicians (DCL-ADHS) giving a clinical diagnosis of ADHD and parents (FBB-ADHD) and physical features (age, weight, height, BMI) using mean scores, correlations and multiple regression.ResultsOur video-activity score showed a high agreement (r = 0.81) with video-based movement ratings, but also considerable associations with age-related physical attributes. After controlling for age-related confounders, the video-activity score showed not the expected association with clinicians’ or parents’ hyperactivity ratings.ConclusionsOur preliminary conclusion is that our video-activity score assesses physical activity but not specific information related to hyperactivity. The general problem of defining and assessing hyperactivity with objective criteria remains.Electronic supplementary materialThe online version of this article (doi:10.1186/s13034-015-0076-1) contains supplementary material, which is available to authorized users.

Motor development of children with attention deficit hyperactivity disorder.

To compare both global and specific domains of motor development of children with attention deficit hyperactivity disorder (ADHD) with that of typically developing children. Two hundred children (50 children with clinical diagnoses of ADHD, according to the DSM-IV-TR and 150 typically developing controls), aged 5 to 10 years, participated in this cross-sectional study. The Motor Development Scale was used to assess fine and global motricity, balance, body schema, and spatial and temporal organization. Between-group testing revealed statistically significant differences between the ADHD and control groups for all domains. The results also revealed a deficit of nearly two years in the motor development of children with ADHD compared with the normative sample. The current study shows that ADHD is associated with a delay in motor development when compared to typically developing children. The results also suggested difficulties in certain motor areas for those with ADHD. These results may point to plausible mechanisms underlying the relationship between ADHD and motor difficulties.