Developmental Attention Deficit Hyperactivity Disorder Research Articles

Efficacy of ADHD Medications in Treating Acquired Attentional Deficits: A Comparative Analysis

Objective: This article aims to critically examine the efficacy of traditional Attention Deficit Hyperactivity Disorder (ADHD) medications in individuals diagnosed with acquired attentional deficits due to brain injury, surgery, or illness. Given the distinct neurobiological underpinnings of developmental ADHD and acquired attentional deficits, this analysis seeks to elucidate the differential outcomes of ADHD medication treatments in these populations. I review the existing literature on the neurodevelopmental basis of ADHD, the pathophysiology of acquired brain injuries leading to attentional deficits, and the pharmacodynamics of common ADHD medications. Comparative studies and case reports detailing the response of patients with acquired attentional deficits to ADHD medications are analyzed to assess efficacy and outcomes. ADHD medications, primarily targeting dopamine and norepinephrine pathways, show variable and unpredictable efficacy in individuals with acquired attentional deficits compared to those with developmental ADHD. Factors influencing medication response include the specific brain regions affected by injury, the extent of damage, and the individual's neuroplasticity. While some patients with acquired deficits exhibit improvements in attention and executive functioning with ADHD medication, others show minimal response, underscoring the complexity of treating attentional deficits arising from brain injury. The differential response to ADHD medications between developmental ADHD and acquired attentional deficits highlights the importance of personalized treatment strategies. For individuals with acquired deficits, a comprehensive approach including cognitive rehabilitation, compensatory strategies, and tailored pharmacotherapy is recommended. Further research is needed to identify predictors of medication response and to develop targeted treatments for this diverse patient population. ADHD medications can play a role in the management of acquired attentional deficits, but their efficacy is less predictable than in developmental ADHD. Understanding the specific neurobiological changes associated with acquired deficits is crucial for optimizing treatment strategies. Future research should focus on developing diagnostic tools and treatments that address the unique needs of individuals with acquired attentional deficits.

Major Visual Impairment in Special Children

Objective: This study aims to identify the major visual impairment among special children. Methods: This cross-sectional study was conducted among 120 children within 3-15 years of age group at a vision therapy centre between April-June of 2023. Results: Low visual acuity was seen in children who had a development delay of 0.79%. In 15.7% of cases of autism spectrum disorder (ASD), astigmatism was present. Nystagmus was seen in 5.8% of cases of cortical visual impairment (CVI). 9.9% of those with attention-deficit/hyperactivity disorder (ADHD) were unable to both accommodate and converge. In 14.0% of cases, the stereo acuity was poor. Ocular mobility was impaired in 9.1% of developmental delay cases, 14.0% of CVI cases, and 25.6% of ASD cases. Fusion was not performed well by 9.9% of ADHD patients. Suppression and diplopia were present in 25.6% of ASD cases, 14.0% of CVI cases, and 9.1% of developmental delay cases. 7.4% of ADHD patients and 12.4% of CVI patients had photophobia. 9.9% of ADHD patients and 14.0% of CVI patients were unable to perform spatial orientation. Children with developmental delays, ASD, ADHD, and CVI were more likely to be impacted and had abnormal visual function.

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

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

Assistência à saúde mental de crianças brasileiras utilizando dados ambulatoriais

ABSTRACT Objective To investigate the clinical epidemiological characteristics of a large data set of visits to outpatient children mental health services in Brazil, as well as to identify relevant relationships between age, sex and three common mental disorders in childhood: pervasive developmental disorders, ADHD, and mild depressive disorders. Methods We extracted data from the Ambulatorial Information System (SIA) part of a public repository, Datasus, regarding child outpatient mental health services in Brazil, from 2008 to 2012. We performed an analysis of the number of visits per one hundred thousand inhabitants and further analyses with logistic regressions for ADHD (F90.0), Pervasive Developmental Disorders (F84.0-F84.9), and Mild Depressive Episode (F32.0) as outcomes, controlling for age, year of the visit, number of new CAPSI stratified by region. Results Attention-deficit hyperactivity disorder (ADHD) was the most common condition identified across the country. The analyses by region showed a high number of visits due to mental retardation in the Northeast and depressive episodes in the South. Regressions showed that older children are less likely to visit outpatient services with a diagnosis of ADHD (F90.0). Conclusions Our analysis shows the conditions which cause the most burden to the child psychiatry outpatient centers in Brazil and relevant differences between regions. This information has immediate use for the training of staff and allocation of resources in each region.

Association of Preeclampsia and Perinatal Complications With Offspring Neurodevelopmental and Psychiatric Disorders

Maternal preeclampsia has been reported to increase the risk of autism spectrum disorder, attention-deficit/hyperactivity disorder (ADHD), and intellectual disability in offspring. However, the association between maternal preeclampsia combined with perinatal complications and neurodevelopmental and psychiatric disorders in offspring is less well documented. To examine the association of maternal preeclampsia, separately and together with perinatal complications, with neurodevelopmental and psychiatric disorders in offspring. This population-based cohort study used data from nationwide registries in Finland to assess all singleton live births (N = 1 012 723) between January 1, 1996, and December 31, 2014. Offspring were followed up until December 31, 2018 (when the oldest reached age 22 years). Exclusion criteria were maternal inpatient psychiatric diagnoses and pregestational diabetes. The study and data analysis were conducted from May 1, 2020, to June 1, 2021. Preeclampsia and perinatal complications (delivery earlier than 34 weeks' gestation and/or small for gestational age). The primary outcomes were neurodevelopmental and psychiatric diagnoses and dispensation of psychotropic drugs among offspring until December 31, 2018. Cox proportional hazards regression analyses were performed to assess the associations. Of 1 012 723 singleton live births (51.1% boys; mean [SD] maternal age at birth, 30.0 [5.4] years; specific data on race and ethnicity were not available in the data set), 21 010 children (2.1%) were exposed to preeclampsia alone, 33 625 children (3.3%) were exposed to perinatal complications alone, and 4891 children (0.5%) were exposed to both preeclampsia and perinatal complications. A total of 93 281 children (9.2%) were diagnosed with a neurodevelopmental or psychiatric disorder. Offspring exposed to both preeclampsia and perinatal complications had an increased risk of any neurodevelopmental or psychiatric disorder after adjusting for potential confounding (adjusted hazard ratio [aHR], 2.11; 95% CI, 1.96-2.26) compared with those not exposed to either preeclampsia or perinatal complications; this risk was higher than exposure to either preeclampsia alone (aHR, 1.18; 95% CI, 1.12-1.23) or perinatal complications alone (aHR, 1.77; 95% CI, 1.72-1.82). Sibling pair analyses did not detect any increase in the risk of neurodevelopmental or psychiatric disorders after exposure to preeclampsia alone, but offspring exposed to both preeclampsia and perinatal complications had increased risks of intellectual disabilities (aHR, 3.24; 95% CI, 1.05-10.06), specific developmental disorders (aHR, 3.56; 95% CI, 2.35-5.41), ADHD and conduct disorders (aHR, 2.42; 95% CI, 1.09-5.39), and other behavioral and emotional disorders (aHR, 2.45; 95% CI, 1.17-5.13). The risk estimates for specific developmental disorders (aHR, 2.82; 95% CI, 2.60-3.05) and ADHD and conduct disorders (aHR, 1.88; 95% CI, 1.65-2.14) were higher among offspring exposed to both preeclampsia and perinatal complications compared with those exposed to perinatal complications alone (aHR, 2.26 [95% CI, 2.18-2.33] and 1.60 [95% CI, 1.52-1.68], respectively). In this study, exposure to both maternal preeclampsia and perinatal complications was associated with intellectual disabilities, specific developmental disorders, ADHD and conduct disorders, and other behavioral and emotional disorders in offspring. For specific developmental disorders and ADHD and conduct disorders, the risk estimates were higher among offspring exposed to both preeclampsia and perinatal complications compared with those exposed to perinatal complications only.

Association of mental disorders and strabismus among South Korean children and adolescents: a nationwide population-based study.

The aim of this study is to determine the association between mental disorders and strabismus in South Korean children and adolescents. Using data from the Korean National Health Claims Database from 2011 to 2017, the prevalence rates of mental illnesses and odds ratio were calculated. Children and adolescents (1-19years) with strabismus and their randomly selected nonstrabismic age- and sex-matched controls (1:1) were enrolled. The odds ratios were adjusted for preterm birth, cerebral palsy, and mental retardation. Subgroup analysis was performed according to sex and the type of strabismus. A total of 327,076 subjects (male, 158,597; female, 168,479) identified as strabismus patients were enrolled. After adjusting for preterm birth, cerebral palsy, and mental retardation, the corrected odds ratio of overall mental illness was 1.10 (95% CI, 1.08-1.12) for the strabismus group compared to the controls: 1.7 (95% CI, 1.62-1.78) for developmental disorder, 1.36 (95% CI, 1.27-1.45) for pervasive developmental disorder (autism), 1.14 (95% CI, 1.10-1.17) for attention-deficit hyperactivity disorder (ADHD), 1.15 (95% CI, 1.05-1.27) for obsessive-compulsive disorder (OCD), 1.08 (95% CI, 1.05-1.11) for pediatric behavioral and emotional disorders, 0.93 (95% CI, 0.88-0.99) for post-traumatic stress disorder (PTSD), and 0.85 (95% CI, 0.82-0.89) for tic disorder. South Korean children and adolescents with strabismus had a higher relative risk for various types of mental disorders such as a developmental disorder, autism, ADHD, and OCD than the controls, whereas they had a relatively lower risk of tic disorder.

Letter to the Editor: The Impact of the COVID-19 Pandemic on the Mental Health of Youth with Developmental Disabilities.

Letter to the Editor: The Impact of the COVID-19 Pandemic on the Mental Health of Youth with Developmental Disabilities.

Developmental and mental health risks among siblings of patients with autism spectrum disorder: a nationwide study

Studies have suggested that unaffected siblings of patients with autism spectrum disorder (ASD) have some other neurodevelopmental abnormalities. However, the risks of mental and developmental disorders have rarely been investigated among unaffected siblings. Using Taiwan's National Health Insurance Research Database, 1304 unaffected siblings born between 1980 and 2010 with ASD probands and 13,040 age-/sex-/family structure-matched controls were included in our study and followed up from 1996 or birth to the end of 2011. Developmental delay, language delay, developmental coordination disorder, attention-deficit hyperactivity disorder (ADHD), anxiety disorders, disruptive behavior disorders, unipolar disorder, and bipolar disorder were identified during the follow-up period. Unaffected siblings were more likely to develop any developmental delay, developmental speech or language disorder, developmental coordination disorder, intelligence disability, ADHD, anxiety disorders, unipolar depression, and disruptive behavior disorders compared with the control group. Brothers of patients with ASD had a higher risk of neurodevelopmental abnormalities, ADHD, anxiety disorders, and disruptive behavior disorders; sisters were prone to having neurodevelopmental abnormalities, ADHD, anxiety disorders, unipolar depression, and disruptive behavior disorders. Unaffected siblings of patients with ASD were prone to developing any developmental or mental disorder later in life. Clinicians and public health officials should pay more attention to the developmental condition and mental health of unaffected siblings of patients with ASD.

Perinatal Factors of Developmental Attention Deficit Hyperactivity Disorder in Children

Background: Attention deficit hyperactivity disorder is a common pediatric neurobehavioral disorder often treated in the primary care setting. It shows a high and chronic level of inattention, impulsivity/hyperactivity and/or both, and can affect more than 2 million school-age children. The researchers are not sure about the exact causes of the disorder, but it seems that apart from genetic factors, perinatal factors seem to dynamically contribute to the development of the disorder. Purpose: The aim of this review was to investigate the perinatal and obstetric factors related to the development of the attention deficit hyperactivity disorder in childhood. Method: An online review of English language studies published from 2002 to 2020, using the Embase, PsychINFO, PubMed and Google Scholar databases. From 1100 studies only 17 were included in the review since they met the inclusion criteria. Conclusions: The results of the review showed that apart from heredity and genetic factors, various conditions in pregnancy or the mother’s way of life in pregnancy, adverse conditions in labor and infancy can contribute on their own or in combination to the development of the attention deficit hyperactivity disorder in childhood. Obstetric vigilance to detect risk factors in pregnancy in combination with the prevention of obstetric complications is the key in preventing attention deficit hyperactivity disorder.

IMPLEMENTATION OF EDUCATIONAL SUPPORT FOR A PUPIL WITH DEVELOPMENTAL DISORDER IN INDIVIDUAL EDUCATION PLAN

The paper aims to propose a process of development of individual educational support based on the analysis of selected items taken from the individual education plans designed for students individually integrated within mainstream primary schools. We analyzed personal files of 18 students diagnosed with developmental learning disorders and ADHD (Attention Deficit Hyperactivity Disorder). The results indicate the general formulation of interventions in educational settings.

Neuro-cognitive Underpinning of Co-morbidity between Developmental Dyslexia and Attention-Deficit Hyperactivity Disorder (ADHD)

Developmental Dyslexia is a specific reading and writing disability despite of normal intelligence, educational instruction and socio-cultural opportunity. Attention-deficit hyperactivity disorder (ADHD) is a condition that affects millions of children and often persists into adulthood. ADHD can include a combination of problems, such as difficulty sustaining attention, hyperactivity and impulsive behaviour. The frequent co-morbidity of dyslexia and ADHD posed the question of the issue whether common causal mechanism can be identified. There are several causal explanation of the co-morbidity between dyslexia and ADHD. Firstly, the symptoms of ADHD associated with dyslexia are a secondary consequence of reading problems (‘phenocopy’ hypothesis). However, the finding could not substantiate in later studies. Therefore, the first aim the present research is to identify the frequency and nature of co-morbidity between dyslexics and ADHD children.
 Developmental Dyslexia and ADHD are some of the most complex developmental disorders that affect children population. These are some of the conditions which affect the ability of the children to benefit from education and engage with surroundings in a meaningful manner. These conditions may occur in isolation, but many times they overlap. These overlapping conditions are termed as co-morbidity, and this may reflect the greater difficulties experienced by the children with a combination of deficits. However, the underlying reasons for these and the subsequent behavioural deficits are not well understood. Thus, the second major goal of the article is to investigate neuro-cognitive underpinning of dyslexia and ADHD. Neuro-cognitive basis presented by prefrontal dorsolateral cortex dysfunction was revealed and executive functions presented by problems in phonological working memory, initiating the activity and multitasking were established.

Association of maternal depression with children's attention deficit hyperactivity disorder.

Family problems are considered to be the main risk factor leading to the development of behavi oural problems during childhood and adolescence as well. A well documented fact in the current literature is that psychopathology of any kind in parents may influence behaviour, personality and appearance of psychopathology in their children. The permanent interaction between children's psychopathology or any kind of developmental disorder on one hand and parental psychopathology on the other, is considered to be one of the most important fields of research during the last decades. The aim of the present study was to review research concerning the relationship between maternal depressive disorder and children's attention deficit hyperactivity disorder (ADHD) among members of the same family, the influence that each disorder has in the appearance and development of the other, and the way that the mother-child relationship is influenced by both. We conducted an electronic search through PubMed to detect articles concerning the association of maternal depressive disorder and children's ADHD among the members of the same family published in English from January 1980 to December 2015. The choice was strictly limited to articles concerning exclusively emotional disorders in mothers and ADHD in their children. This process concluded with the electronic research of bibliographic citations of the identified articles, or related articles, in order to locate additional sources. Considering as a fact the interaction between this developmental disorder, ADHD, and mother's psychological profile which is maternal depression for the present research, we report the following: among the 27 articles found, 24 concerned the influence of the mother's depression to the child's ADHD, and the remaining 3 concerned their genetic association. There were important limitations found as well. Despite the fact that all the studies included a control group, many of them did have a follow-up and were short-term studies. Their results were mostly heterogenous and therefore their meta-analysis proved impossible. There was evidence concerning the association between the two disorders as both maternal depressive disorder and children's ADHD influence each other through multiple psychosocial and biological factors. Nevertheless, more data is needed from well structured, homogenous studies, especially in the field of genetics, in order to document this association.

Secondary attention-deficit/hyperactivity disorder following perinatal and childhood stroke: impact on cognitive and academic outcomes

ABSTRACTThis cross-sectional retrospective clinical research study examines a large group of children followed within a pediatric stroke program and a developmental attention-deficit/hyperactivity disorder (ADHD) clinic at the Hospital for Sick Children, between May 2004 and June 2016. All children with a history of stroke who participated in a neuropsychological assessment between the ages of 4 and 18 years were considered for inclusion. From a sample of 275 participants with a history of stroke, 36 children (13.1%) received a diagnosis of secondary ADHD. Children with secondary ADHD were younger at the time of stroke and more likely to be identified as having a presumed perinatal stroke and persistent seizures than children without secondary ADHD diagnoses. There were no differences in pattern of lesion, size, or laterality between children who developed secondary ADHD and those who did not. Children with secondary ADHD had the lowest scores across all cognitive and academic measures compared to children with stroke-only and developmental ADHD. Findings highlight the added risk of receiving a diagnosis of secondary ADHD following pediatric stroke. Implications for future research and directed intervention are discussed.

Neurodevelopmental disorders in children with epilepsy

Neurodevelopmental disorders, including intellectual disability, autistic-spectrum disorders, speech disorders, attention deficit hyperactivity disorder (ADHD), learning disabilities, are more prevalent in children with epilepsy compared with the general population. Marked developmental delay and regression of acquired skills are characteristic of epileptic encephalopathies. Conditions, in which neurodevelopmental disorders are associated with the marked epileptiform EEG activity, while clinical epileptic seizures are absent, represent a serious problem. The authors consider the features of epilepsy with electrical status epilepticus during slow-wave sleep, pseudo-Lennox syndrome, Landau-Kleffner syndrome, children autistic epileptiform regression, autosomal-dominant rolandic epilepsy with verbal dispraxy and a combination of epilepsy and subclinical epileptiform EEG activity with developmental dysphasia and ADHD. In addition to the optimization of basic treatment with antiepileptic drugs (AEDs), nootropic drugs which do not increase epileptiform activity (hopantenic acid), are recommended.

The Relation Between ADHD and Cognitive Profiles of Children with NF1

Despite well-accepted findings of a “downward shift” in intellectual functioning in children with neurofibromatosis type 1 (NF1), research has not examined the contribution of the individual indices in this lower performance on intelligence (IQ) measures. Although 30–50 % of children with NF1 meet criteria for a diagnosis of attention deficit/hyperactivity disorder (ADHD), research has not established the relation between ADHD and intellectual profiles in these children. To clarify these issues, this study examined the Wechsler Intelligence Scale for Children, Fourth Edition (WISC-IV) profiles of children with NF1, with and without comorbid ADHD, using a comparison group of children with developmental ADHD. We found that rather than an overall lowering of IQ, children with NF1 demonstrated an uneven intellectual profile. While verbal abilities were generally preserved, nonverbal, working memory, and processing speed abilities were lower than the population norms. Children with NF1 and comorbid ADHD showed significantly lower performance on tests of working memory than children with NF1 without ADHD or children with developmental ADHD. These results suggest that global intellect is inadequate in describing the cognitive phenotype in children with NF1 and that in children with NF1 comorbid ADHD may manifest as additional cognitive burden with respect to working memory.

Attention Problems in Children with Epilepsy. How is the Long-Term Outcome?

Aims: Attention deficit hyperactivity disorder (ADHD) is one of the most common childhood disorders and frequently seen in epilepsy as well. The prevalence of ADHD in epilepsy is significantly higher than in the general pediatric population. How these attention problems develop over the years is however not clear. We therefore, evaluated the severity of attention problems in epileptic children at late childhood and assessed it again in adolescence. Data were being compared with attention problems of children with developmental ADHD.

Review of current evidence on the impact of pesticides, polychlorinated biphenyls and selected metals on attention deficit / hyperactivity disorder in children

The aim of this review was to investigate the association between attention deficit / hyperactivity disorder (ADHD) or ADHD-related symptoms and industrial chemicals, such as organophosphates and organochlorine pesticides, polychlorinated biphenyls (PCBs), lead, mercury and manganese. Medline, PubMed and EBSCO searches were performed to identify the studies that analyzed the association of prenatal and postnatal child exposure to such toxicants and ADHD or ADHD-related symptoms. The review is restricted to human studies published in English in peer-reviewed journals since 2000. Most of the presented studies focused on pesticides, PCB and lead. The impact of mercury and manganese was investigated less frequently. The findings indicate that children's exposure to organophosphate pesticides may cause symptoms consistent with pervasive developmental disorder, ADHD or attention problems. Exposures to organochlorine pesticides and PCBs were associated with ADHD-like behaviors such as alertness, quality of alert response, and cost of attention. The studies provided evidence that blood lead level below 10 μg/dl was associated with ADHD or ADHD-related symptoms. Information on the association between exposure to mercury and neurotoxicity is limited, and requires further confirmation in future research. Two studies indicated that exposure to manganese is related to ADHD; such exposure and its impact on children neurodevelopment need to be further investigated. Future studies should use a prospective design with multiple biological samples collected over time for better assessment of exposure and its critical windows. Additionally, inclusion of potential confounding factors and co-exposures is crucial.

Attention‐deficit/hyperactivity disorder in childhood epilepsy: A neuropsychological and functional imaging study

Children with epilepsy have a significant risk for attention-deficit/hyperactivity disorder (ADHD), which is often accompanied by deficits in working memory performance. However, it is not yet clear whether there are specific differences in the underlying mechanisms of working memory capability between children with epilepsy-related ADHD and those with developmental ADHD. There is evidence that methylphenidate can improve the behavioral difficulties in children with developmental ADHD. Whether this medication has the same effect on ADHD symptoms in patients with epilepsy is not yet well understood. The aim of the present study is, therefore, to evaluate whether boys with epilepsy-related ADHD and developmental ADHD share a common behavioral, pharmacoresponsive, and neurofunctional pathophysiology. Seventeen boys with diagnosed combined epilepsy/ADHD, 15 boys with developmental ADHD, and 15 healthy controls (aged 8-14 years) performed on working memory tasks (N-back) while brain activation was recorded using functional magnetic resonance imaging. Each patient was tested twice: once after the intake of methylphenidate and once without in a counterbalanced order. On a behavioral level, we show that boys with epilepsy-related ADHD as well as those with developmental ADHD performed similarly poorly on tasks with high cognitive load when compared to healthy controls, and that intake of methylphenidate improved performance almost to normal levels in both ADHD groups. On the functional level, both patient groups showed similar reductions of activation in all relevant parts of the functional network of working memory when compared to controls. Of interest, intake of methylphenidate did not significantly alter this activity pattern. Our data show strong similarities between epilepsy-related and developmental ADHD on the behavioral, pharmacoresponsive, and neural level, favoring the view that ADHD with and without epilepsy shares a common underlying neurobehavioral pathophysiology.

Theoretical and clinical implications of using an ADHD framework to understand attention, concentration, and executive functioning deficits in pediatric cancer survivors

F or the past two decades, researchers have consistently identified a pattern of neurocognitive deficits (e.g., attention/concentration difficulties and deficits in executive functioning) in many childhood cancer survivors that may significantly impact their academic performance, social/interpersonal relationships, and vocational success if left unidentified or untreated. As such, it is imperative that researchers focus on understanding the specific nature of these deficits, their precise etiology, and efficacious treatment approaches. To better understand the nature of these deficits, a number of research teams have used an attention-deficit/hyperactivity disorder (ADHD) conceptual framework to guide their research efforts. Findings suggest that indeed many childhood survivors of leukemia [1] and brain tumors [2] evidence attentional difficulties consistent with the inattentive subtype of ADHD. In this issue of Pediatric Blood & Cancer, Kahalley et al. further explore rates of occurrence of ADHD and secondary ADHD (SADHD) in pediatric cancer survivors and compare those rates to that in the general population. The term SADHD refers to an ADHD-like presentation acquired from a non-developmental presentation, such as a traumatic brain injury, or for the purposes of their research, neuro-toxic cancer treatments. Importantly, they conclude that the clinical presentation of cancer survivors does not resemble that of either ADHD or SADHD, and suggest that the current DSM-IV diagnostic criteria and nomenclature may not characterize the types of deficits that pediatric cancer survivors manifest. We would like to underscore the problems in utilizing a classic, developmental ADHD framework for understanding cognitive late effects in childhood cancer survivors, and argue that there are inherent theoretical and clinical shortcomings to this approach. Our first theoretical concerns center on the issue of diagnostic specificity. Identification of SADHD as a potential diagnosis in pediatric cancer survivors that only differs from conventional/premorbid ADHD with regard to etiology and onset, ignores the very characteristics that distinguish ADHD from other childhood disorders. That is, age of onset, pervasiveness, and impairment are particularly important in discriminating ADHD from other childhood disorders, given the characteristic symptoms of ADHD are not pathognomic. For example, attention difficulties are frequently associated with almost all diagnoses of childhood. Children with anxiety or mood disorders are often restless, fidgety, and may struggle to attend to class lectures due to the interference of persistent ruminations. Racing thoughts, pressured speech, and/or delusions associated with early onset bipolar disorder are expected to create similar interference with attentional processes, while children with autism spectrum disorders are frequently described as ‘‘being in their own world.’’ To sum, it is illogical to conclude that an ADHD framework should be invoked simply because a similar cluster of symptoms are evident in childhood cancer survivors. A second concern revolves around the issue of etiological differences and underlying cognitive processes. Neurological correlates of developmental ADHD-related deficits include the pre-frontal and frontal cortices, basal ganglia [3], and dopaminergic and noradrenergic systems [4]. Strong evidence of ADHD as a neurological disorder may mislead researchers to conclude damage to an associated brain region secondary to intrathecal chemotherapy, radiation, and/or surgery would result in the same disorder. This fails to consider the unique developmental trajectory and underlying core processes associated with developmental ADHD, as well as potential differences in neural plasticity. Within the last few decades, executive functions such as behavioral inhibition [5] and working memory [6], have been increasingly identified as potential core deficits of ADHD. Affected children with a diagnosis of SADHD are expected to exhibit similar executive function deficits if SADHD is a comparable disorder. To date, relatively few studies have examined the effect of acute lymphocytic leukemia and/or interferon-alpha and chemotherapy treatments on executive functions, and findings have been relatively equivocal [7], and/or based on parent ratings scales rather than rigorous experimental/ neuropsychological methods. Importantly, studies indicate that the phenotype of developmental ADHD changes over time such that affected individuals tend to exhibit fewer problems related to hyperactivity in adulthood [8]. This finding likely reflects that ADHD results from delayed maturation of cortical areas involved in motor control and attention, and treatments modalities often change (e.g., change from MPH to Adderal) according to changes in symptoms. It is not clear if childhood cancer survivors exhibit a similar change in their symptoms over time, particularly since the etiology is a traumatic insult to their brain (e.g., chemotherapy), rather than a complex interaction of genetics and environmental influences. Recent studies of the Cogmed working memory training reveal promising findings that suggest the neural plasticity of children

An Investigation Into Etiological Pathways of DCD and ADHD Using a Monozygotic Twin Design

We previously described a co-twin control design using questionnaire data on monozygotic twins discordant and concordant for developmental coordination disorder (DCD) and attention deficit hyperactivity disorder (ADHD). Our results suggested that DCD and developmental ADHD had different causal pathways, and that second-born twins were at higher risk for oxygen perfusion problems than first-born twins. In the current study we further explored our findings using DNA confirmed zygosity and assessments of 4 female and 10 male sets of monozygotic twins, aged 8 to 17 years, from the first study. Using the McCarron Assessment of Neuromuscular Development (MAND), twice as many second- as first-born twins met criteria for DCD. Second-born twins attained significantly lower scores on 1-minute Apgar, MAND Gross Motor, Bimanual Dexterity and Neuromuscular Development Index. Seven of the nine twins who met criteria for DCD experienced perinatal oxygen perfusion problems. This supported findings in the first study of an association between perinatal oxygen perfusion problems and DCD, and our hypothesis that DCD and cerebral palsy have similar causal pathways. We found similar numbers of males and females discordant for DCD. On telephone interview using the Diagnostic Interview Schedule for Children Parent Interview, the only first-, and all five second-born twins who met criteria for ADHD had an inattentive component - three Inattentive; three Combined. All twins positive for ADHD were male. This adds support to our hypothesis that ADHD symptoms found in some participants may reflect secondary ADHD associated with environmental factors, rather than developmental ADHD.