Replication of the latent class structure of Attention-Deficit/Hyperactivity Disorder (ADHD) subtypes in a sample of Australian twins

BACKGROUND: Previous efforts to subtype Attention-Deficit/Hyperactivity Disorder (ADHD) using latent class analysis (LCA) applied to DSM-IV symptom profiles of adolescent female twins from Missouri (USA) have identified distinct classes within the domains of inattention, hyperactivity-impulsivity and combined-type problems. The objective of the current report is to determine if the latent class structure of ADHD subtypes can be replicated in a culturally distinct sample of female and male Australian twins. METHOD: LCA was applied to parent-report DSM-IV ADHD symptom profiles of N=2,848 child and adolescent Australian twins and compared to North American findings. Separate models were fitted for females (N= 1,432) and males (N= 1,416). RESULTS: The most congruent latent ADHD classes across samples included a non-symptomatic class, three mild-moderate and two severe classes. Also present within samples was a rare hyperactive-impulsive class and a unique class, the structure of which was idiosyncratic across samples. Mean symptom endorsement and individual symptom endorsement probabilities for each of the stable classes were similar across samples. Consistent with previous findings, there was substantial overlap between the DSM-IV inattentive and combined subtypes with the severe inattentive and severe combined latent classes. However, DSM-IV inattentive and combined subtypes were distributed over several latent classes in each sample, and a substantial proportion of individuals with no DSM-IV diagnosis were also assigned to these severe classes. CONCLUSIONS: Results from LCA using an Australian twin sample replicate six of the eight latent class subtypes previously reported using Missouri female twins and extend the findings to male twins. LCA and DSM-IV systems of ADHD classification identify different phenotypic groups, and the basis of this disparity merits further investigation.     

Medication Use in Youth With Autism and Attention-Deficit/Hyperactivity Disorder

ObjectiveChildren with autism spectrum disorder (ASD) may benefit from medication to treat a diverse array of behaviors and health conditions common in this population including co-occurring conditions associated with ASD, such as attention-deficit/hyperactivity disorder (ADHD) and anxiety. However, prescribing guidelines are lacking and research providing national estimates of medication use in youth with ASD is scant. We examined a nationally representative sample of children and youth ages 6 to 17 with a current diagnosis of ASD to estimate the prevalence and correlates of psychotropic medication.MethodsThis study used data from the 2016 and 2017 National Survey of Children's Health. We estimated unadjusted prevalence rates and used multivariable logistic regression to estimate the odds of medication use in children and youth across 3 groups: those with ASD-only, those with ASD and ADHD, and those with ADHD-only.ResultsTwo thirds of children ages 6 to 11 and three quarters of youth ages 12 to 17 with ASD and ADHD were taking medication, similar to children (73%) and youth with ADHD-only (70%) and more than children (13%) and youth with ASD-only (22%). There were no correlates of medication use that were consistent across group and medication type. Youth with ASD and ADHD were more likely to be taking medication for emotion, concentration, or behavior than youth with ADHD-only, and nearly half took ASD-specific medication.ConclusionsThis study adds to the literature on medication use in children and youth with ASD, presenting recent, nationally representative estimates of high prevalence of psychotropic drug use among children with ASD and ADHD.     

Prevalence of Attention-Deficit/Hyperactivity Disorder Symptoms in Preschool-aged Iranian Children

Objective

The aim of this study was to determine the prevalence of attention-deficit/hyperactivity disorder (ADHD) symptoms in Iranian preschool children based on evaluations by parents and teachers because a thorough understanding of epidemiologic features of ADHD symptoms in preschool children is important for prevention and management.

Methods

Children between the ages of three and six attending kindergarten participated in this study. For the survey, 37 kindergartens were selected by multistage (stratified cluster random) sampling, consisting of 2213 children with a design effect equal to 1.5. A 19-item observer-rating questionnaire was generated to assess ADHD symptoms in children within the last 6 months. This questionnaire was used by both teachers and parents to assess ADHD behavior in participating children.

Findings

Of 1403 children aged 3–6 years, 362 were classified as having ADHD symptoms according to their parent evaluation [25.8% (23.6–28.1%)] and 239 according to their teachers evaluation [17% (14.1–20.4%)]. Child rank among siblings, mother''s education level, and interest in aggressive television programs were all independent explanatory variables according to parents’ evaluation. Gender, parent education, child rank, single parent and interest in aggressive television programs were all independent explanatory variables according to teachers’ evaluation.

Conclusion

Our findings reveal a large discrepancy in the prevalence of ADHD symptoms in preschool children based on evaluation by parents and teachers. Thus, it seems that the ADHD screening should be performed in multiple settings in order to identify children who need further investigations.     

儿童注意缺陷多动障碍诊断及治疗

儿童注意缺陷多动障碍（ADHD）是儿童保健门诊中最常见的儿童行为问题，对个人、家庭和社会产生深远的负面影响，故近年日益受到重视。2005年以来我国在国内外主要期刊上发表相关论文150余篇，诊断标准和治疗方法不断完善和规范。现将2004年以来我国ADHD的诊断进展报告如下，并着重强调在诊断和治疗过程中可能存在问题及注意事项，为正确诊断和合理治疗儿童ADHD提供帮助。     

Visual behaviour of ADHD children during an attention test: an almost forgotten variable. Attention-Deficit Hyperactivity Disorder

The goal of this study was to examine whether looking away behaviour of ADHD children interferes with their test performance. ADHD and normal children carried out two continuous performance tests (CPTs): one with a regular interstimulus interval (ISI), and the other with an irregular ISI. Children were instructed to push a response button when a target stimulus was presented on the monitor. The children's visual behaviour was recorded and scored offline. A micro-analysis of the visual behaviour indicated that ADHD children timed their looking away behaviour in the regular CPT: i.e. they looked away from the monitor and back in the interval between two succeeding stimuli. As a result they did not miss stimuli. Timing of looking away was less possible in the CPT with the irregular ISI. In this condition, looking away interfered with the ADHD children's task accuracy. In sum, looking away behaviour had a negative effect on the accuracy of test performance of ADHD children when stimuli were unpredictable. Looking away behaviour was not associated with the slower reaction times of the ADHD children. Hence, the often reported slowness of ADHD children is not to be explained by their visual behaviour.     

电生理检查在注意缺陷多动障碍诊治中的应用

注意缺陷多动障碍（ADHD）是儿童期最常见、最复杂的情绪与行为障碍之一。其病因尚不明确，诊断和治疗都有较大难度，目前缺乏客观指标来进行诊断及评估疗效。电生理检查作为无创、经济、简单易行的方法，在ADHD的临床应用方面有重要意义及前景。     

Etiology and pathogenesis of Attention-deficit Hyperactivity Disorder (ADHD): significance of prematurity and perinatal hypoxic-haemodynamic encephalopathy

Attention-deficit Hyperactivity Disorder (ADHD), defined as a disorder of awareness with impul-sivity, has lately been characterized as a dysfunction of the striatum (neostriatum = globus pallidus + putamen). This structure is in a unique position for contextual analysis and samples information from almost the entire cortex through its spiny neurons. The etiology is heterogeneous, with genetic as well as lesional factors. Among the latter, pre- and perinatal events are prominent. Advances in the understanding of the role of fetal circulatory insufficiency with loss of autoregulation and systemic hypotension have drawn attention to the vulnerability of watershed regions, including the striatum. Not only circulatory facts are important for this selectivity, however. The anatomical characteristics, with convergent glutaminergic afferent synaptic transmission from almost the entire cortex contribute to the vulnerability in ischemia-induced liberation of glutamate: The striatum becomes the victim of its virtue. Repeated hypoxic-ischemic events are particularly common in prematurity, a fact which seems to explain the high incidence of ADHD in this patient group. The magnitude of the problem is increasing with the increased survival rate among premature infants.     

Reasons Why Children and Adolescents With Attention-Deficit/Hyperactivity Disorder Stop and Restart Taking Medicine

Objective

To describe the prevalence of reasons why children and adolescents stop and restart attention-deficit/hyperactivity disorder (ADHD) medicine and whether functional impairment is present after stopping medicine.

Attention-Deficit/Hyperactivity Disorder,Stimulant Therapy,and the Patient with Congenital Heart Disease: Evidence and Reason

Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder of childhood, and congenital heart disease (CHD) is the most common form of birth defect. Children with CHD are at increased risk for neurodevelopmental disorders such as ADHD. Stimulant medications, specifically methylphenidates and amphetamines, are frequently prescribed and effective in reducing the symptoms of ADHD. Despite their efficacy and long history of use, the safety of these medications has recently come into question due to isolated reports describing sudden unexplained death of children undergoing treatment. This review summarizes the current literature on the cardiovascular risks associated with the use of pharmacologic therapy for ADHD, with an emphasis on patients who had CHD.     

Incidence of Enuresis and Encopresis Among Children With Attention-Deficit/Hyperactivity Disorder in a Population-Based Birth Cohort

ObjectiveThis study reports the incidence of enuresis and encopresis among children with attention-deficit/hyperactivity disorder (ADHD) versus those without ADHD.MethodsSubjects included 358 children (74.5% boys) with research-identified ADHD from a 1976 to 1982 population-based birth cohort (n = 5718) and 729 (75.2% boys) non-ADHD control subjects from the same birth cohort, matched by gender and age. All subjects were retrospectively followed from birth until a diagnosis of enuresis or encopresis was made or last follow-up before 18 years of age. The complete medical record for each subject was reviewed to obtain information on age of initial diagnosis of an elimination disorder, frequency and duration of symptoms, and identification of exclusionary criteria specified by DSM-IV, with confirmation of the diagnosis by expert consensus.ResultsChildren with ADHD were 2.1 (95% confidence interval [CI], 1.3–3.4; P = .002) times more likely to meet DSM-IV criteria for enuresis than non-ADHD controls; they were 1.8 (95% CI, 1.2–2.7; P = .006) times more likely to do so than non-ADHD controls when less stringent criteria for a diagnosis of enuresis were employed. Though not significant, children with ADHD were 1.8 (95% CI, 0.7–4.6; P = .23) times more likely to meet criteria for encopresis than non-ADHD controls. The relative risk was 2.0 (95% CI, 1.0–4.1; P = .05) when a less stringent definition for encopresis was utilized.ConclusionsChildren with ADHD are more likely than their peers without ADHD to develop enuresis with a similar trend for encopresis.     

注意缺陷多动障碍儿童临床特点及长期服用哌甲酯的安全性

目的：通过对注意缺陷多动障碍（ADHD）儿童临床分型、治疗前后脑电图（EEG）监测，探讨儿童ADHD临床特点及长期服用哌甲酯的安全性。方法：将2005年1月～2006年6月首都儿科研究所附属儿童医院神经内科确诊的ADHD患儿121例，予哌甲酯10～20mg／d口服，观察6～18个月。于治疗前及治疗后3、6个月予ADHD评定量表-Ⅳ-父母版（ADHDRS-IV-Parent：Inv）、临床总体印象-总体严重度量表（CGI-ADHD-S）行疗效评定，治疗前、治疗后6个月行EEG检查。结果：1．分型特点：ADHD 121例中ADHD-156例，ADHD-C54例，ADHD-HI 11例，分别占46．3％、44．6％、9．1％；2．男女患儿发病比：男104例，女17例；男女比例为6．1：1；3．疗效及EEG：哌甲酯治疗有效者85例（有效率70．2％）；治疗前、治疗后6个月EEG检查均未见异常。结论：女性ADHD患儿少于男性。临床主要以学习困难为主述，以注意力缺陷型为主；哌甲酯长期服用对ADHD患儿EEG无影响。     

Computed tomography and radiation risks: what pediatric health care providers should know

Computed tomography (CT) is an extremely valuable diagnostic tool. Recent advances, particularly multidetector technology, have provided increased and more diverse applications. However, there is also the potential for inappropriate use and unnecessary radiation dose. Because some data indicate that low-dose radiation (such as that in CT) may have a significant risk of cancer, especially in young children, it is important to limit CT radiation by following the ALARA (as low as reasonably achievable) principle. There is a variety of strategies to limit radiation dose, including performing only necessary examinations, limiting the region of coverage, and adjusting individual CT settings based on indication, region imaged, and size of the child. The pediatric health care provider has a pivotal role in the performance of CT and may be the only individual who discusses these important CT radiation issues with the child and family. For this reason, this article will summarize the issues with CT patterns of use and radiation risk, and provide dose reduction strategies pertinent to pediatric health care providers.