Differential effects of atomoxetine on executive functioning and lexical decision in attention-deficit/hyperactivity disorder and reading disorder

OBJECTIVE

The effects of a promising pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD), atomoxetine, were studied on executive functions in both ADHD and reading disorder (RD) because earlier research demonstrated an overlap in executive functioning deficits in both disorders. In addition, the effects of atomoxetine were explored on lexical decision.

METHODS

Sixteen children with ADHD, 20 children with ADHD + RD, 21 children with RD, and 26 normal controls were enrolled in a randomized placebo-controlled crossover study. Children were measured on visuospatial working memory, inhibition, and lexical decision on the day of randomization and following two 28-day medication periods.

RESULTS

Children with ADHD + RD showed improved visuospatial working memory performance and, to a lesser extent, improved inhibition following atomoxetine treatment compared to placebo. No differential effects of atomoxetine were found for lexical decision in comparison to placebo. In addition, no effects of atomoxetine were demonstrated in the ADHD and RD groups.

CONCLUSION

Atomoxetine improved visuospatial working memory and to a lesser degree inhibition in children with ADHD + RD, which suggests differential developmental pathways for co-morbid ADHD + RD as compared to ADHD and RD alone.

CLINICAL TRIAL REGISTRY

B4Z-MC-LYCK, NCT00191906; http://clinicaltrials.gov/ct2/show/NCT00191906.

Societal costs and quality of life of children suffering from attention deficient hyperactivity disorder (ADHD)

BACKGROUND

The impact of attention deficit hyperactive disorder (ADHD) in the Netherlands on health care utilisation, costs and quality of life of these children, as well as of their parents is unknown.

OBJECTIVE

The aim of this study was to assess the direct medical costs of patients suffering from ADHD and their quality of life as well as the direct medical costs of their mothers.

STUDY DESIGN

We selected a group of 70 children who were being treated by a paediatrician for ADHD based on the DSM-IV diagnostic criteria for ADHD. For comparison's sake, we also included a non-matched group of 35 children with behaviour problems and 60 children with no behaviour problem from a large school population-based study on the detection of ADHD. We collected information on the health care utilisation of the children applying the Trimbos and iMTA questionnaire on Costs associated with Psychiatric illness' (TiC-P). Their health related quality of life was collected by using the Dutch 50-item parent version of the Child Health Questionnaire (CHQ PF-50). Measurements were at baseline and at 6 months. Subsequently, we collected data on the health utilisation of the mothers and their production losses due to absence from work and reduced efficiency.

RESULTS

The mean direct medical costs per ADHD patient per year were euro 2040 or euro 1173 when leaving out one patient with a long-term hospital admission, compared to euro 288 for the group of children with behaviour problems and euro 177 for the group of children with no behaviour problems. The direct medical costs for children who had psychiatric co-morbidities were significantly higher compared to children with ADHD alone. The mean medical costs per year for the mothers of the ADHD patients were significantly higher than for the mothers of the children with behaviour problems and the mothers of children with no behaviour problems respectively euro 728, euro 202 and euro 154. The physical summary score showed no significant differences between the groups. However, the score on the Psychosocial Summary Score dimension was significantly lower for ADHD patients compared to the scores of the children in the two other samples. The mean annual indirect costs due to absence from work and reduced efficiency at work were euro 2243 for the mothers of the ADHD patients compared to euro 408 for the mothers of children with behaviour problems and euro 674 for the mothers of children with no behaviour problems.

CONCLUSION

Our study showed that the direct medical costs of ADHD patients were relatively high. Additionally, our study indicated that ADHD appears to be accompanied by higher (mental) health care costs for the mothers of ADHD patients and by increased indirect costs for this group.

Study design, baseline patient characteristics and intervention in a cross-cultural framework: results from the ADORE study

OBJECTIVE

To describe the methodology and to present the baseline findings of the Attention-deficit/hyperactivity Disorder Observational Research in Europe (ADORE) study, the primary objective of which is to describe the relationship between treatment regimen prescribed and quality of life of children with ADHD in actual practice.

METHODS

In this 2-year prospective observational study, data on diagnosis, prescribed treatment and outcomes of ADHD were collected at seven time points by paediatricians and child psychiatrists on 1,573 children recruited in 10 European countries. The data presented here from the 1,478 patients included in the analyses describe the baseline condition, initial treatment regimen prescribed and quality of life of families with children with ADHD.

RESULTS

Patients had a mean age of 9.0 years (SD 2.5) and 84% were male. Physicians diagnoses were made using DSM-IV (43%), ICD-10 (32%) and both DSM-IV and ICD-10 (12%). Mean age of awareness of a problem was 5.1 years, suggesting an average delay of approximately 4 years between awareness and diagnosis of ADHD. Baseline ADHD rating scale scores (physician-rated) indicated moderate to severe ADHD. Parent-rated SDQ scores were in agreement and suggested significant levels of co-existing problems. CGI-S, CGAS and CHIP-CE scores also indicated significant impairment. Patients were offered the following treatments after the initial assessment: pharmacotherapy (25%), psychotherapy (19%), combination of pharmacotherapy and psychotherapy (25%), other therapy (10%) and no treatment (21%).

CONCLUSION

The ADORE study shows that ADHD is similarly recognised across 10 European countries and that the children are significantly impaired across a wide range of domains. In this respect, they resemble children described in previous ADHD samples.

Executive functioning in boys with ADHD: primarily an inhibition deficit?

This study was aimed at: (1) testing whether boys with Attention Deficit/Hyperactivity Disorder (ADHD) demonstrate a deficit in response inhibition and deficits in other executive functions (EF), or alternatively, demonstrate a deficit in only response inhibition; (2) investigating which role associated factors, such as IQ, age, and performance on non-EF tasks play in EF in ADHD; (3) studying the association between the three different forms of inhibition studied here. Boys with ADHD were compared with normal control (NC) boys on five domains of executive functioning: inhibition (inhibition of a prepotent response, inhibition of an ongoing response, and interference control), planning, set-shifting, working memory, and verbal fluency. Boys with ADHD demonstrated deficits in interference control, inhibition of an ongoing response, planning, and letter fluency. After controlling for age, IQ, and non-EF measures, none of the EF deficits in ADHD remained. Finally, correlations between different inhibition measures were generally low, and correlations within domains of inhibition were not higher than correlations between domains of inhibition. This calls into question the distinctiveness of the different forms of response inhibition.

The effect of methylphenidate on three forms of response inhibition in boys with AD/HD

The current study was aimed at (a) investigating the effect of three doses methylphenidate (MPH) and placebo on inhibition of a prepotent response, inhibition of an ongoing response, and interference control in Attention Deficit/Hyperactivity Disorder (AD/HD), and (b) studying dose-response relations for the three forms of response inhibition. To meet these aims, the following tasks were selected: two versions of the Stop Paradigm for inhibition of a prepotent response, a Circle Tracing Task and a recently developed Follow Task for inhibition of an ongoing response, and the Stroop Color-Word Test and an Eriksen Flanker Task for interference control. These tasks were administered to 23 boys with AD/HD during four treatment conditions: 5 mg MPH, 10 mg MPH, 20 mg MPH, and placebo. A pseudorandomized, multiple-blind, placebo-controlled, within-subject design was used. As hypothesized, inhibitory control in children with AD/HD improved under MPH compared to placebo. However, this effect was only significant for inhibition of a prepotent response and inhibition of an ongoing response (as measured by the Follow Task), but not for interference control. The relation between treatment condition and response was linear. However, this linear relation was due to improved inhibitory control under MPH compared to placebo, because no effects of MPH dose were observed for any of the response inhibition measures.

Unilateral delayed opercularization in a case of Sotos' syndrome (Cerebral Gigantism)

A case of Sotos' syndrome (cerebral gigantism) is described. Pneumencephalography, performed at the age of 15 days, revealed abnormal separation of the opercula on the right. By comparing the contours with developmental anatomical features of this area it agreed with a foetal development of 24 weeks gestational age. Bilateral carotid angiography was normal. CT showed normal development of the Sylvian area at the age of 27 months.