Attention deficit hyperactivity disorder: a Rasch analysis of the SWAN Rating Scale

Placebo-related improvement with methylphenidate treatment in children with ADHD

Non-specific effects of methylphenidate treatment, including expectancy and regression to the mean effects, contribute to the overall effect of methylphenidate on attention-deficit/hyperactivity disorder (ADHD) symptoms. Knowledge on the extent to which non-specific effects contribute to the overall effect and whether regression to the mean explains part of the non-specific effects, is currently lacking. A double-blind, randomized, placebo-controlled, cross-over trial was used to compare parent and teacher ratings of child ADHD symptoms at baseline and during treatment with placebo and 5, 10, 15 and 20 mg of methylphenidate, twice daily. Participants were 5-13-year-old children with a DSM-5 diagnosis of ADHD (N = 45). The extent to which non-specific effects contributed to the effects of methylphenidate was determined by ADHD symptom reductions observed with placebo versus reductions observed with active doses of methylphenidate. The influence of regression to the mean was examined by estimating the contribution of baseline ADHD symptom severity to the effects observed with placebo treatment. Data were analyzed using multilevel analyses. We observed significant non-specific effects of methylphenidate for parent-rated ADHD symptoms, but not for teacher-rated symptoms. For parent reported hyperactive/impulsive symptoms, higher baseline symptoms predicted larger effects with placebo, indicating regression to the mean effects. For parent-reports, a significant part of the overall effect of methylphenidate treatment is explained by non-specific effects. Our findings stress the importance of taking non-specific effects into account when evaluating methylphenidate treatment, by including teacher-reports and using a double baseline assessment during titration. Comparing active medication with a placebo in the titration trial has the potential to identify non-specific effects.

Comorbid ADHD and Pediatric Sickle Cell Disease: Prevalence and Risk Factors

Sickle cell disease (SCD) is a genetic blood condition that places youth at increased risk for deficits in complex attention suggestive of increased risk for Attention-Deficit/Hyperactivity Disorder (ADHD). We used systematic screening to assess the prevalence of ADHD in a clinic-based sample of youth with SCD and explored factors related to ADHD. Caregivers of 107 children with SCD (ages 7-11 years) completed routine psychosocial screening which included inattentive symptoms of ADHD. Follow-up diagnostic procedures were completed for patients with elevated inattentive symptoms to assess for ADHD diagnoses. Biomedical and social-environmental variables were examined from the screening and medical records. Twenty-six percent of patients showed elevated inattentive symptoms with 13% meeting diagnostic criteria for ADHD diagnoses. Most children (75%) who met criteria for ADHD had not been previously diagnosed. Disease severity did not predict inattentive symptoms or ADHD diagnoses, though a measure of chronic inflammation was associated with ADHD. Family functioning was related to elevated inattentive symptoms but not ADHD diagnoses. Children with SCD show relatively high rates of ADHD with many cases not detected through routine care. Screening for ADHD as part of hematology care may be a feasible strategy to improve identification and access to intervention.

Improving Methylphenidate Titration in Children with Attention-Deficit/Hyperactivity Disorder (ADHD): A Randomized Controlled Trial Using Placebo-Controlled Titration Implemented in Clinical Practice

BACKGROUND AND OBJECTIVES

Concerns exist regarding the rising use of methylphenidate. A double-blind, placebo-controlled methylphenidate titration (PCT) for children with attention-deficit/hyperactivity disorder (ADHD) has shown potential to improve titration (i.e., detection of placebo responders and larger ADHD symptom improvement) in experimental settings. This study aims to determine if these advantages can be transferred to clinical settings.

METHOD

Children (aged 5-13 years) with an ADHD diagnosis and an indication to start methylphenidate (MPH) treatment were recruited. Participants were randomized to PCT or care as usual (CAU) in a 1:1 ratio followed by a 7-week randomized controlled trial (T1) and 6-month, naturalistic, open-label follow-up (T2). Parents, teachers, and physicians rated ADHD symptoms, ADHD medication use, MPH dosing, and treatment satisfaction using questionnaires.

RESULTS

A total of 100 children were enrolled and randomized to PCT (n = 49) or CAU (n = 51). In the PCT group, we found 8.2% placebo responders, 16.3% non-responders, and 65.3% responders to MPH. With PCT compared with CAU, a significantly larger number of children discontinued MPH (T1: 24.5 vs 5.9%, p = 0.009; T2: 41.7 vs 10.4%, p < 0.001) and refrained from using other pharmacological treatment (T1: 20.4 vs 3.9%, p = 0.013; T2: 20.83 vs 6.25%, p = 0.002). At both timepoints, there were no significant differences between the groups in the average dose of MPH, ADHD symptoms, or treatment satisfaction.

CONCLUSIONS

PCT can be used to improve detection of children who do not benefit from MPH, and may therefore potentially reduce overtreatment of ADHD with MPH.

Properties of white matter tract diffusivity in children with developmental dyslexia and comorbid attention deficit/hyperactivity disorder

BACKGROUND

Developmental dyslexia (DD) and attention deficit/hyperactivity disorder (ADHD) are highly comorbid neurodevelopmental disorders. Individuals with DD or ADHD have both been shown to have deficits in white matter tracts associated with reading and attentional control networks. However, white matter diffusivity in individuals comorbid with both DD and ADHD (DD + ADHD) has not been specifically explored.

METHODS

Participants were 3rd and 4th graders (age range = 7 to 11 years; SD = 0.69) from three diagnostic groups ((DD (n = 40), DD + ADHD (n = 22), and typical developing (TD) (n = 20)). Behavioral measures of reading and attention alongside measures of white matter diffusivity were collected for all participants.

RESULTS

DD + ADHD and TD groups differed in mean fractional anisotropy (FA) for the left and right Superior Longitudinal Fasciculus (SLF)-Parietal Terminations and SLF-Temporal Terminations. Mean FA for the DD group across these SLF tracts fell between the lower DD + ADHD and higher TD averages. No differences in mean diffusivity nor significant brain-behavior relations were found.

CONCLUSIONS

Findings suggest that WM diffusivity in the SLF increases along a continuum across DD + ADHD, DD, and TD.

Parents' perspectives on a smartwatch intervention for children with ADHD: Rapid deployment and feasibility evaluation of a pilot intervention to support distance learning during COVID-19

Distance learning in response to the COVID-19 pandemic presented tremendous challenges for many families. Parents were expected to support children's learning, often while also working from home. Students with Attention Deficit Hyperactivity Disorder (ADHD) are at particularly high risk for setbacks due to difficulties with organization and increased risk of not participating in scheduled online learning. This paper explores how smartwatch technology, including timing notifications, can support children with ADHD during distance learning due to COVID-19. We implemented a 6-week pilot study of a Digital Health Intervention (DHI) with ten families. The DHI included a smartwatch and a smartphone. Google calendars were synchronized across devices to guide children through daily schedules. After the sixth week, we conducted parent interviews to understand the use of smartwatches and the impact on children's functioning, and we collected physiological data directly from the smartwatch. Our results demonstrated that children successfully adopted the use of the smartwatch, and parents believed the intervention was helpful, especially in supporting the development of organizational skills in their children. Overall, we illustrate how even simple DHIs, such as using smartwatches to promote daily organization and task completion, have the potential to support children and families, particularly during periods of distance learning. We include practical suggestions to help professionals teach children with ADHD to use smartwatches to improve organization and task completion, especially as it applies to supporting remote instruction.

Evaluation of the Pain Impact Index for Community-Dwelling Older Adults Through the Application of Rasch Modelling

OBJECTIVE

Evaluate the Pain Impact Index, a simple, brief, easy-to-use, and novel tool to assess the impact of chronic pain in community-dwelling older adults.

METHODS

A Rasch modelling analysis was undertaken in Stata using a partial credit model suited to the Likert-type items that comprised the Index. The Index was evaluated for ordering of category thresholds, unidimensionality, overall fit to the Rasch model, measurement bias (Differential Item Functioning, DIF), targeting, and construct validity.

RESULTS

The four-item Pain Impact Index was self-completed by 6454 community-dwelling Australians who were aged at least 70 years and experienced pain on most days. Two items showed evidence of threshold disordering, and this was resolved by collapsing response categories (from 5 to 3) for all items. The rescored Index conformed to the unidimensionality assumption and had satisfactory fit with the Rasch model (analyses conducted on a reduced sample size to mitigate the potential for overpowering: n = 377, P > 0.0125, power > 77%). When considering uniform DIF, the most frequent sources of measurement bias were age, knee pain, and upper back pain. When considering nonuniform DIF, the most frequent source of measurement bias was knee pain. The Index had good ability to differentiate between respondents with different levels of pain impact and had highest measurement precision for respondents located around the average level of pain impact in the study sample. Both convergent and discriminant validity of the Index were supported.

CONCLUSION

The Pain Impact Index showed evidence of unidimensionality, was able to successfully differentiate between levels of pain impact, and had good evidence of construct validity.

Measuring strengths and weaknesses in dimensional psychiatry

BACKGROUND

The Extended Strengths and Weaknesses Assessment of Normal Behavior (E-SWAN) reconceptualizes each diagnostic criterion for selected DSM-5 disorders as a behavior, which can range from high (strengths) to low (weaknesses). Initial development focused on Panic Disorder, Social Anxiety, Major Depression, and Disruptive Mood Dysregulation Disorder.

METHODS

Data were collected from 523 participants (ages 6-17). Parents completed each of the four E-SWAN scales and traditional unidirectional scales addressing the same disorders. Distributional properties, Item Response Theory Analysis (IRT), and Receiver Operating Characteristic (ROC) curves were used to assess and compare the performance of E-SWAN and traditional scales.

RESULTS

In contrast to the traditional scales, which exhibited truncated distributions, all four E-SWAN scales had symmetric distributions. IRT analyses indicate the E-SWAN subscales provided reliable information about respondents throughout the population distribution; traditional scales only provided reliable information about respondents at the high end of the distribution. Predictive value for DSM-5 diagnoses was comparable to prior scales.

CONCLUSIONS

E-SWAN bidirectional scales can capture the full spectrum of the population distribution of behavior underlying DSM disorders. The additional information provided can better inform examination of inter-individual variation in population studies, as well as facilitate the identification of factors related to resiliency in clinical samples.

A Randomized Effectiveness Trial of a Behavioral Teacher Program Targeting ADHD Symptoms

OBJECTIVE

This study investigated the effectiveness of the Positivity & Rules Program (PR program), a behavioral teacher program targeting ADHD symptoms in the classroom involving both student-focused and classroom-focused programs.

METHOD

Primary school children with ADHD symptoms ( N = 114) were randomly assigned to the PR program ( n = 58) or control group ( n = 56). Teacher and parent ratings were used to assess behavioral, social, and emotional functioning at baseline, during and after the intervention. Intervention effects were assessed using intention-to-treat multilevel analyses.

RESULTS

Teachers reported positive effects on ADHD symptoms and social skills (.01 < f² > .36). Effects did not generalize to the home setting.

CONCLUSION

The PR program holds promise for improving classroom behavior in children with ADHD symptoms and might prevent escalation of problem behavior.

Working Memory With Emotional Distraction in Monolingual and Bilingual Children

Extensive work has demonstrated the benefits of bilingualism on executive functioning (EF) across the lifespan. Concurrently, other research has shown that EF is related to emotion regulation (ER), an ability that is integral to healthy socio-emotional development. However, no research to date has investigated whether bilingualism-related advantages in EF can also be found in emotional contexts. The current study examined the performance of 93 children who were 9-years old, about half of whom were bilingual, on the Emotional Face N-Back Task, an ER task used to assess the interference effect of emotional processing on working memory. Bilingual children were more accurate than monolingual children in both 1-back and 2-back conditions but were significantly slower than monolingual children on the 2-back condition. There were significant effects of emotional valence on reaction time, but these did not differ across language groups. These results confirm previous research showing better EF performance by bilinguals, but no differences in ER were found between language groups. Findings are discussed in the context of our current understanding of the ER literature with potential implications for previously unexplored differences between monolingual and bilingual children.

Inattentiveness and Language Abilities in Preschoolers: A Latent Profile Analysis

Growing evidence suggests that early symptoms of inattentiveness may affect the language development and academic success of young children. In the present study, we examined the extent to which profiles of inattentiveness and language could be discerned within a heterogeneous group of preschoolers attending early childhood special education programs (n = 461). Based on parent-reported observations of children's symptoms of inattentiveness and direct assessments of children's language skills (grammar, vocabulary, and narrative ability), three distinct profiles were identified. The three groups, representing levels of severity (at risk, almost average, above average), differed not only by their end of year performance, but also with respect to which their abilities changed over the course of the academic year. Children in the poorest performing profile had poorer mean scores in the spring of their preschool year on all measures, but exhibited patterns of gain that exceeded or equaled their peers in higher-performing groups, in the domains of vocabulary and grammar. Examination of subsequent kindergarten reading skills suggested that profile differences remained consistent. Findings underscore the associations between early symptoms of inattentiveness and language difficulties, and further indicate that these relations extend to the acquisition of early reading skills. Future research is needed to corroborate these findings with more robust measures of attention, and to understand the long-term associations between inattentiveness, language and literacy, and potential effects on these associations from early intervention.

Identifying potentially marker symptoms of attention-deficit/hyperactivity disorder

Background

For the diagnosis of attention-deficit/hyperactivity disorder (ADHD), the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) proposes that adherence to six symptoms in either group (inattention and hyperactivity/impulsivity) will lead to the diagnosis of one of three presentations of the disorder. Underlying this diagnostic algorithm is the assumption that the 18 symptoms have equal relevance for the diagnosis of ADHD, all are equally severe, and all have the same power to detect the presence of the disorder in all its degrees of severity, without considering the possibility of using marker symptoms. However, several studies have suggested that ADHD symptoms differ in both their power to discriminate the presence of the disorder and the degree of severity they represent. The aim of the present study was to replicate the results of previous research by evaluating the discriminative capacity and relative severity of ADHD symptoms, as well as to extend the investigation of this topic to Spanish-speaking Latin American samples.

Methods

The properties of ADHD symptoms rated by the parents of 474 Chilean children were analyzed. Symptom parameters were estimated using the graded response model.

Results

The results suggest that symptoms of ADHD differ substantially in both the accuracy with which they reflect the presence of the disorder, and their relative severity. Symptoms “easily distracted by extraneous stimuli” and “have difficulty sustaining attention in tasks” (inattention) and “is on the go, acting as if driven by motor” (hyperactivity/impulsivity) were the most informative, and those with relatively lower severity thresholds.

Discussion

The fact that symptoms differ substantially in the probability of being observed conditionally to the trait level suggests the need to refine the diagnostic process by weighting the severity of the symptom, and even to assess the possibility of defining ADHD marker symptoms, as has been done in other disorders.

Moderators Influencing the Effectiveness of a Behavioral Teacher Program

Objective: This study assessed which moderators influenced the effectiveness of a low-intensive behavioral teacher program for children with symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD).

Methods: Primary school children (N = 114) with ADHD symptoms in the classroom were randomly assigned to the intervention program (n = 58; 91% male) or control group (n = 56; 77% male). Multilevel regression analyses assessed differential treatment gains of the intervention program in terms of ADHD symptoms and social skills. Moderators included demographic characteristics (gender, age, parental educational level), severity and comorbidity of problem behavior (ADHD symptoms, conduct and internalizing problems), social functioning, and classroom variables (teaching experience, class size).

Results: Results revealed larger program effects for older children and children from highly educated families and smaller beneficial effects for children with comorbid conduct or anxiety problems.

Conclusion: The intervention program seems more beneficial for highly educated families and children without comorbid problem behavior, but more intensive treatments appear necessary for children facing additional challenges.

ClinicalTrials.gov registration number: NCT02518711

Home Environmental and Behavioral Risk Indices for Reading Achievement

The goal of this study was to identify home environmental and temperament/behavior variables that best predict standardized reading comprehension scores among school-aged children. Data from 269 children aged 9-16 (M = 12.08; SD = 1.62) were used in discriminant function analyses to create the Home and Behavior indices. Family income was controlled in each index. The final Home and Behavior models each classified around 75% of cases correctly (reading comprehension at grade level vs. not). Each index was then used to predict other outcomes related to reading. Results showed that Home and/or Behavior accounted for 4-7% of the variance in reading fluency and spelling and 20-35% of the variance in parent-rated problems in math, social anxiety, and other dimensions. These metrics show promise as environmental and temperament/behavior risk scores that could be used to predict and potentially screen for further assessment of reading related problems.

Hierarchy and Psychometric Properties of ADHD Symptoms in Spanish Children: An Application of the Graded Response Model

The Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria assume that the 18 symptoms carry the same weight in an Attention Deficit with Hyperactivity Disorder (ADHD) diagnosis and bear the same discriminatory capacity. However, it is reasonable to think that symptoms may differ in terms of severity and even in the reliability with they represent the disorder. To test this hypothesis, the aim of this study was to calibrate in a sample of Spanish children (age 4–7; n = 784) a scale for assessing the symptoms of ADHD proposed by Diagnostic and Statistical Manual of Mental Disorders, IV-TR within the framework of Item Response Theory. Samejima’s Graded Response Model was used as a method for estimating the item difficulty and discrimination parameters. The results showed that ADHD subscales (Attention Deficit and Hyperactivity / Impulsivity) had good psychometric properties and had also a good fit to the model. However, relevant differences between symptoms were observed at the level of severity, informativeness and reliability for the assessment of ADHD. This finding suggests that it would be useful to identify the symptoms that are more important than the others with regard to diagnosing ADHD.

Interactions between levels of attention ability and levels of bilingualism in children's executive functioning

Attention difficulty is associated with poor performance on executive functioning (EF) tasks, yet EF is enhanced in bilingual children. However, no research to date has investigated the possible interaction between bilingualism and attention ability in children to determine the consequences for EF when both are present. We assessed a sample of typically developing children who were 8 to 11 years old for their ability in attention control and level of bilingualism on the basis of questionnaires completed by parents and teachers. Children performed three tasks requiring aspects of EF: stop signal task (inhibition), flanker task (interference control), and frogs matrices task (spatial working memory). Results from hierarchical regressions confirmed that both attention ability and bilingualism contributed to performance on the EF tasks. Where interaction effects were significant, they showed that attention ability was a stronger predictor for an inhibition task, namely stop signal, and bilingualism a stronger predictor for an interference task, namely flanker. Furthermore, these results allow us to discuss the relation between EF and attention ability.

Are all the 18 DSM-IV and DSM-5 criteria equally useful for diagnosing ADHD and predicting comorbid conduct problems?

In view of ICD-11 revision, we evaluate whether the 18 DSM-IV diagnostic items retained by DSM-5 could be further improved (i) in predicting ADHD 'caseness' and 'impairment' and (ii) discriminating ADHD without CD (ADHD - CD) cases from ADHD with CD (ADHD + CD) cases. In a multi-centre study sample consisting of 1497 ADHD probands and 291 unaffected subjects, 18 diagnostic items were examined for redundancy; then each item was evaluated for association with caseness, impairment and CD status using Classical Test Theory, Item-Response Theory and logistic regression methods. First, all 18 DSM-IV items contributed significantly and independently to the clinical diagnosis of ADHD. Second, not all the DSM-IV items carried equal weighting. "Often loses things", "forgetfulness" and "difficulty sustaining attention" mark severity for Inattentiveness (IA) items and "often unduly noisy", "exhibits a persistent pattern of restlessness", "leaves seat in class" and "often blurts out answers" for Hyperactivity/Impulsivity (HI) items. "Easily distracted", "inattentive to careless mistakes", "often interrupts" and "often fidgets" are associated with milder presentations. In the IA domain, "distracted" yields most information in the low-severity range of the latent trait, "careless" in the mid-severity range and "loses" in the high-severity range. In the HI domains, "interrupts" yields most information in the low-severity range and "motor" in the high-severity range. Third, all 18 items predicted impairment. Fourth, specific ADHD items are associated with ADHD + CD status. The DSM-IV diagnostic items were valid and not redundant; however, some carried more weight than others. All items were associated with impairment.

Development and applications of the SWAN rating scale for assessment of attention deficit hyperactivity disorder: a literature review

This study reviewed the use of the Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviors (SWAN) rating scale in diagnostic and evolutive approaches to attention deficit hyperactivity disorder (ADHD) and in correlational studies of the disorder. A review of articles published in indexed journals from electronic databases was conducted and 61 articles on the SWAN scale were analyzed. From these, 27 were selected to a) examine use of SWAN in research on attention disorders and b) verify evidence of its usefulness in the areas of genetics, neuropsychology, diagnostics, psychiatric comorbidities, neuroimaging, pharmacotherapy, and to examine its statistical reliability and validity in studies of diverse populations. This review of articles indicated a growing use of the SWAN scale for diagnostic purposes, for therapy, and in research on areas other than ADHD, especially when compared with other reliable scales. Use of the scale in ADHD diagnosis requires further statistical testing to define its psychometric properties.

Longitudinal relations among inattention, working memory, and academic achievement: testing mediation and the moderating role of gender

Introduction. Behavioral inattention, working memory (WM), and academic achievement share significant variance, but the direction of relationships across development is unknown. The aim of the present study was to determine whether WM mediates the pathway between inattentive behaviour and subsequent academic outcomes. Methods. 204 students from grades 1-4 (49.5% female) were recruited from elementary schools. Participants received assessments of WM and achievement at baseline and one year later. WM measures included a visual-spatial storage task and auditory-verbal storage and manipulation tasks. Teachers completed the SWAN behaviour rating scale both years. Mediation analysis with PROCESS (Hayes, 2013) was used to determine mediation pathways. Results. Teacher-rated inattention indirectly influenced math addition fluency, subtraction fluency and calculation scores through its effect on visual-spatial WM, only for boys. There was a direct relationship between inattention and math outcomes one year later for girls and boys. Children who displayed better attention had higher WM scores, and children with higher WM scores had stronger scores on math outcomes. Bias-corrected bootstrap confidence intervals for the indirect effects were entirely below zero for boys, for the three math outcomes. WM did not mediate the direct relationship between inattention and reading scores. Discussion. Findings identify inattention and WM as longitudinal predictors for math addition and subtraction fluency and math calculation outcomes one year later, with visual-spatial WM as a significant mediator for boys. Results highlight the close relationship between inattention and WM and their importance in the development of math skills.

The SWAN captures variance at the negative and positive ends of the ADHD symptom dimension

OBJECTIVE

The Strengths and Weaknesses of ADHD Symptoms and Normal Behavior (SWAN) Rating Scale differs from previous parent reports of ADHD in that it was designed to also measure variability at the positive end of the symptom spectrum.

METHOD

The psychometric properties of the SWAN were tested and compared with an established measure of ADHD, the Disruptive Behavior Rating Scale (DBRS).

RESULTS

The SWAN demonstrates comparable validity, reliability, and heritability to the DBRS. Furthermore, plots of the SWAN and DBRS reveal heteroscedasticity, which supports the SWAN as a preferred measure of positive attention and impulse regulation behaviors.

CONCLUSION

The ability of the SWAN to measure additional variance at the adaptive end of the ADHD symptom dimensions makes it a promising tool for behavioral genetic studies of ADHD.

Inattention, hyperactivity, and emergent literacy: different facets of inattention relate uniquely to preschoolers' reading-related skills

Although extant studies indicate that there is a strong association between attention deficit/hyperactivity disorder and reading ability in elementary school children, knowledge regarding the relation between inattentive and hyperactive/impulsive behaviors and emergent literacy in preschool children is less established. This study examined the unique and overlapping relations between measures that assess inattention and hyperactivity/impulsivity and emergent literacy skills in preschool children. Participants included 204 preschool children (M age = 56 months, 50.9% female, 79.8% European American). Behavioral rating scales were completed by teachers, and the Continuous Performance Test (CPT) and the Test of Preschool Early Literacy were completed by the preschoolers. Across measures, inattention was a unique correlate of emergent literacy skills, whereas hyperactivity/impulsivity was not. Both rating scales and the CPT indices of inattention were uniquely associated with emergent literacy skills. These results suggest that these measures are assessing different manifestations of inattention that are both unique correlates of early reading skills.

The reliability and validity of the English and Spanish Strengths and Weaknesses of ADHD and Normal behavior rating scales in a preschool sample: continuum measures of hyperactivity and inattention

OBJECTIVE

To evaluate the reliability and validity of the English and Spanish versions of the Strengths and Weaknesses of ADHD-symptom and Normal-behavior (SWAN) rating scale.

METHOD

Parents of preschoolers completed both a SWAN and the well-established Strengths and Difficulties Questionnaire (SDQ) on two separate occasions over a span of 3 months; instruments were in the primary language of the family (English or Spanish).

RESULTS

Psychometric properties for the English and Spanish versions of the SWAN were adequate, with high internal consistency and moderate test-retest reliability. Skewness and kurtosis statistics for the SWAN were within the range expected for a normally distributed population. The SWAN also demonstrated adequate convergent and discriminant validity in correlations with the various subscales of the SDQ.

CONCLUSION

Psychometric properties of both the English and Spanish versions of the SWAN indicate that it is a reliable and valid instrument for measuring child attention and hyperactivity. The stability of ratings over time in this preschool sample was moderate, which may reflect the relative instability of these characteristics in preschool children.

Long-term effects of prenatal cigarette smoke exposure on behavior dysregulation among 14-year-old offspring of teenage mothers

In this prospective study, we examined the long-term effects of prenatal cigarette smoke exposure (PCSE) on behavioral dysregulation (BD) in the offspring of adolescent mothers. The adolescent mothers (mean age = 16; range = 12-18; 70% African American) were interviewed about their tobacco use during pregnancy. Offspring were followed to age 14 years (n = 318). Indices of BD outcomes included aggression, rule breaking, externalizing, social problems, attention, distractibility and activity. Multiple measures and multiple informants were used for each construct. Regression analyses were conducted to test if PCSE predicted the BD outcomes, adjusting for demographic and maternal psychological characteristics, and for prenatal exposure to other substances. Independent effects of PCSE were found. Exposed offspring had more aggressive, social, and externalizing problems on both the maternal report and the adolescent self-report measures. They were more active, had more attention problems and greater difficulty with distraction and task orientation. Most PCSE effects were found from first trimester exposure and from exposure to as few as 10 cigarettes per day. These results are consistent with previous findings in this cohort when offspring were 6 and 10 years old, demonstrating that the effects of prenatal cigarette smoke exposure can be identified early and persist into adolescence.

Motivation deficit in ADHD is associated with dysfunction of the dopamine reward pathway

Attention-deficit hyperactivity disorder (ADHD) is typically characterized as a disorder of inattention and hyperactivity/impulsivity but there is increasing evidence of deficits in motivation. Using positron emission tomography (PET), we showed decreased function in the brain dopamine reward pathway in adults with ADHD, which, we hypothesized, could underlie the motivation deficits in this disorder. To evaluate this hypothesis, we performed secondary analyses to assess the correlation between the PET measures of dopamine D2/D3 receptor and dopamine transporter availability (obtained with [(11)C]raclopride and [(11)C]cocaine, respectively) in the dopamine reward pathway (midbrain and nucleus accumbens) and a surrogate measure of trait motivation (assessed using the Achievement scale on the Multidimensional Personality Questionnaire or MPQ) in 45 ADHD participants and 41 controls. The Achievement scale was lower in ADHD participants than in controls (11±5 vs 14±3, P<0.001) and was significantly correlated with D2/D3 receptors (accumbens: r=0.39, P<0.008; midbrain: r=0.41, P<0.005) and transporters (accumbens: r=0.35, P<0.02) in ADHD participants, but not in controls. ADHD participants also had lower values in the Constraint factor and higher values in the Negative Emotionality factor of the MPQ but did not differ in the Positive Emotionality factor-and none of these were correlated with the dopamine measures. In ADHD participants, scores in the Achievement scale were also negatively correlated with symptoms of inattention (CAARS A, E and SWAN I). These findings provide evidence that disruption of the dopamine reward pathway is associated with motivation deficits in ADHD adults, which may contribute to attention deficits and supports the use of therapeutic interventions to enhance motivation in ADHD.

DRD4 and DAT1 in ADHD: Functional neurobiology to pharmacogenetics

Attention deficit/hyperactivity disorder (ADHD) is a common and potentially very impairing neuropsychiatric disorder of childhood. Statistical genetic studies of twins have shown ADHD to be highly heritable, with the combination of genes and gene by environment interactions accounting for around 80% of phenotypic variance. The initial molecular genetic studies where candidates were selected because of the efficacy of dopaminergic compounds in the treatment of ADHD were remarkably successful and provided strong evidence for the role of DRD4 and DAT1 variants in the pathogenesis of ADHD. However, the recent application of non-candidate gene strategies (eg, genome-wide association scans) has failed to identify additional genes with substantial genetic main effects, and the effects for DRD4 and DAT1 have not been replicated. This is the usual pattern observed for most other physical and mental disorders evaluated with current state-of-the-art methods. In this paper we discuss future strategies for genetic studies in ADHD, highlighting both the pitfalls and possible solutions relating to candidate gene studies, genome-wide studies, defining the phenotype, and statistical approaches.

DSM-V and the future diagnosis of attention-deficit/hyperactivity disorder

In general, recommendations for the DSM-V and future diagnoses of psychiatric disorders include a dimensional approach to complement the standard categorical approach. For the assessment of attention-deficit/hyperactivity disorder (ADHD), dimensional approaches to supplement the rigid categorical approach of the DSM-IV abound. Historically, dimensions based on severity of symptoms of ADHD and severity of general psychopathology have been used. General dimensional approaches described by a workgroup organized by the American Psychiatric Association are reviewed to provide background and context for a discussion of old and new dimensional approaches to complement future categorical diagnosis of ADHD in the DSM-V.

Evaluating dopamine reward pathway in ADHD: clinical implications

CONTEXT

Attention-deficit/hyperactivity disorder (ADHD)--characterized by symptoms of inattention and hyperactivity-impulsivity--is the most prevalent childhood psychiatric disorder that frequently persists into adulthood, and there is increasing evidence of reward-motivation deficits in this disorder.

OBJECTIVE

To evaluate biological bases that might underlie a reward/motivation deficit by imaging key components of the brain dopamine reward pathway (mesoaccumbens).

DESIGN, SETTING, AND PARTICIPANTS

We used positron emission tomography to measure dopamine synaptic markers (transporters and D(2)/D(3) receptors) in 53 nonmedicated adults with ADHD and 44 healthy controls between 2001-2009 at Brookhaven National Laboratory.

MAIN OUTCOME MEASURES

We measured specific binding of positron emission tomographic radioligands for dopamine transporters (DAT) using [(11)C]cocaine and for D(2)/D(3) receptors using [(11)C]raclopride, quantified as binding potential (distribution volume ratio -1).

RESULTS

For both ligands, statistical parametric mapping showed that specific binding was lower in ADHD than in controls (threshold for significance set at P < .005) in regions of the dopamine reward pathway in the left side of the brain. Region-of-interest analyses corroborated these findings. The mean (95% confidence interval [CI] of mean difference) for DAT in the nucleus accumbens for controls was 0.71 vs 0.63 for those with ADHD (95% CI, 0.03-0.13, P = .004) and in the midbrain for controls was 0.16 vs 0.09 for those with ADHD (95% CI, 0.03-0.12; P < or = .001); for D(2)/D(3) receptors, the mean accumbens for controls was 2.85 vs 2.68 for those with ADHD (95% CI, 0.06-0.30, P = .004); and in the midbrain, it was for controls 0.28 vs 0.18 for those with ADHD (95% CI, 0.02-0.17, P = .01). The analysis also corroborated differences in the left caudate: the mean DAT for controls was 0.66 vs 0.53 for those with ADHD (95% CI, 0.04-0.22; P = .003) and the mean D(2)/D(3) for controls was 2.80 vs 2.47 for those with ADHD (95% CI, 0.10-0.56; P = .005) and differences in D(2)/D(3) in the hypothalamic region, with controls having a mean of 0.12 vs 0.05 for those with ADHD (95% CI, 0.02-0.12; P = .004). Ratings of attention correlated with D(2)/D(3) in the accumbens (r = 0.35; 95% CI, 0.15-0.52; P = .001), midbrain (r = 0.35; 95% CI, 0.14-0.52; P = .001), caudate (r = 0.32; 95% CI, 0.11-0.50; P = .003), and hypothalamic (r = 0.31; CI, 0.10-0.49; P = .003) regions and with DAT in the midbrain (r = 0.37; 95% CI, 0.16-0.53; P < or = .001).

CONCLUSION

A reduction in dopamine synaptic markers associated with symptoms of inattention was shown in the dopamine reward pathway of participants with ADHD.