Biomedical subjects

Jan K Buitelaar

Publications and source records attributed to Jan K Buitelaar.

At least 19 recordsLinked to original sources

PubMed2007

Attachment in toddlers with autism and other developmental disorders.

Attachment was assessed in toddlers with Autistic Disorder (n=20), Pervasive Developmental Disorder (n=14), Mental Retardation (n=12), Language Development Disorder (n=16), and a non-clinical comparison group (n=18), using the Strange Situation Procedure (SSP). Children in the clinical groups were more often disorganized and less often securely attached. Severity of autism was associated with more attachment insecurity, and lower developmental level increased the chance for disorganized attachment. Attachment disorganization was related to increased heart rate during the SSP. Controlling for basal cortisol and developmental level, more autistic symptoms predicted lower cortisol responses to the SSP. The findings support the importance of disorganized attachment for children with autism.

Arousal↗

PubMed2007

Prolactin release in children treated with risperidone: impact and role of CYP2D6 metabolism.

OBJECTIVE: Little is known about the role of CYP2D6 polymorphism in risperidone-induced prolactin release in children. METHOD: Twenty-five children (aged 5-15 years) with pervasive developmental disorders were genotyped for CYP2D6 polymorphisms. Serum prolactin, risperidone, and 9-hydroxyrisperidone were assessed at baseline and after 8 weeks of risperidone treatment (mean dosage, 0.06 +/- 0.03 mg/kg/d). After 24 weeks of treatment, prolactin was measured in a subsample of 15 children. Adverse effects were evaluated using a clinician-rated survey. RESULTS: Mean +/- SD prolactin levels increased from 7.8 +/- 8.0 ng/mL at baseline to 33.2 +/- 12.8 ng/mL at week 8 (P < 0.001), with a slight decrease to 28.8 +/- 13.6 ng/mL at week 24. At week 8, serum prolactin level was positively correlated with dose per kilogram (r = 0.648, P < 0.001), number of functional CYP2D6 genes (J = 2.117, P = 0.034), and serum 9-hydroxyrisperidone concentration (r = 0.664, P = 0.001) and was negatively correlated with the risperidone/9-hydroxyrisperidone ratio (r = -0.571, P = 0.004) but not with risperidone concentration (r = -0.243, P = 0.264) nor age (r = 0.072, P = 0.733). Prolactin elevation was not associated with adverse effects. CONCLUSIONS: Low-to-intermediate doses of risperidone induced a 4-fold prolactin increase in children without a clear development of tolerance up to 6 months. CYP2D6 ultrarapid metabolism may be a risk factor for more pronounced prolactin elevation.

Adolescent↗

PubMed2006

Does maternal prenatal stress adversely affect the child's learning and memory at age six?

Prenatal maternal stress has been shown to affect postnatal development in animals and humans. In animals, the morphology and function of the offspring's hippocampus is negatively affected by prenatal maternal stress. The present study prospectively investigated the influence of prenatal maternal stress on learning and memory of 112 children (50 boys, 62 girls, Age: M=6.7 years, SD=8.4 months), with the Test of Memory and Learning (TOMAL). Maternal stress levels were determined three times during pregnancy by self-report questionnaires. Furthermore, maternal saliva cortisol samples were used as a measure of hypothalamus-pituitary-adrenal axis functioning. Results of hierarchical multivariate regression analyses showed that maternal life events measured during the first part of pregnancy were negatively associated with the child's attention/concentration index, while controlling for overall IQ, gender, and postnatal stress. No associations were found between prenatal maternal cortisol and the offspring's learning and memory.

Adult↗

PubMed2006

A randomized, double-blind study of continuation treatment for attention-deficit/hyperactivity disorder after 1 year.

BACKGROUND: The efficacy of atomoxetine in maintaining symptom response following 1 year of treatment was assessed in children and adolescents (n = 163) with DSM-IV defined attention-deficit/hyperactivity disorder (ADHD). METHODS: Subjects had previously responded to atomoxetine acutely and had completed 1 year of double-blind atomoxetine treatment. They were then randomly assigned in double-blind fashion to continued atomoxetine or placebo substitution for 6 months. RESULTS: Atomoxetine was superior to placebo in preventing relapse (Wilcoxon test, p = .008) and in maintaining symptom response (ADHD Rating Scale IV score, p < .001). Among subjects assigned to discontinuation, the magnitude of symptom return was generally to a level of severity less than that observed at study entry. CONCLUSIONS: Following 1 year of treatment with atomoxetine, continued treatment over the ensuing 6 months was associated with superior outcomes compared with placebo substitution. However, there was considerable variability between individuals in the magnitude of symptom return after drug discontinuation, suggesting that some subjects treated with atomoxetine for a year with good results may consolidate gains made during drug treatment and could benefit from a medication-free trial to assess the need for ongoing drug treatment.

Adolescent↗

PubMed2006

Ethnic differences in parental detection of externalizing disorders.

BACKGROUND: Previous research has reported lower treatment rates for externalizing disorders among non-Western children as compared to Western children. Ethnic differences in parental detection may be an explanation for this discrepancy. AIMS: In a cross-sectional study among the four largest ethnic groups in the Netherlands, namely Dutch, Moroccan, Turkish and Surinamese, we examined the influence of ethnicity on parental detection of behavioural disorders. METHOD: A total of 270 children (aged 6-10 years) and their parents were interviewed regarding psychiatric disorders and socio-demographic data. Sensitivity and specificity were calculated by using standard definitions, with adjustment for parental educational level. RESULTS: Sensitivity to detect any externalizing disorder and ADHD in particular was significantly lower among Moroccan and Surinamese parents when compared to Dutch parents. Sensitivity to detect ADHD tended to be lower among Turkish parents. Specificity to detect any externalizing disorder was higher among Moroccan and Turkish parents. Specificity to detect ADHD was higher among Moroccan parents and tended to be higher among Turkish parents. CONCLUSIONS: The detection rate of externalizing disorders is markedly lower among non-Dutch parents than among Dutch parents. This finding emphasizes the importance of taking parents' cultural context into account when appraising their report on possible externalizing disorders in their children.

Attention Deficit Disorder with Hyperactivity↗

PubMed2006

A comparison of North American versus non-North American ADHD study populations.

Few large, prospective clinical studies in Europe have assessed the validity and applicability of research methods used to study ADHD in North America. To assess comparability of study populations, we examined baseline patient characteristics from a group of North American studies against those of a large European/African/Australian study. All studies used identical diagnostic assessments and inclusion criteria, with ADHD diagnosis and the presence of comorbid psychiatric conditions confirmed using the KSADS-PL. Raters were trained and assessed to ensure uniform diagnostic and symptom severity rating standards. Six hundred and four patients (mean age = 10.2 years) enrolled in the non-North American study, and 665 patients (mean age = 10.4 years) enrolled in the North American study. The proportion of girls was higher in the North American studies (29.2% vs. 10.4%, p < 0.001). In both groups, most patients had a positive family history of ADHD and previous stimulant treatment. Fewer had the inattentive subtype of ADHD, and mean severity was slightly higher in the non-North American study. Results demonstrate that, when a uniform set of rigorous, standardized diagnostic criteria are used by skilled clinicians, the patient populations identified are generally similar. This supports the practice of generalizing results from treatment studies across geographies.

Adrenergic Uptake Inhibitors↗

PubMed2006

Screening for autistic spectrum disorder in children aged 14-15 months. II: population screening with the Early Screening of Autistic Traits Questionnaire (ESAT). Design and general findings.

A two-stage protocol for screening for autistic spectrum disorders (ASD) was evaluated in a random population of 31,724 children aged 14-15 months. Children were first pre-screened by physicians at well-baby clinics using a 4-item screening instrument. Infants that screened positive were then evaluated during a 1.5-h home visit by a trained psychologist using a recently developed screening instrument, the 14-item Early Screening of Autistic Traits Questionnaire (ESAT). Children with 3 or more negative scores were considered to be at high-risk of developing ASD and were invited for further systematic psychiatric examination. Eighteen children with ASD were identified. The group of children with false positive results had related disorders, such as Language Disorder (N = 18) and Mental Retardation (N = 13).

Autistic Disorder↗

PubMed2006

Screening for autistic spectrum in children aged 14 to 15 months. I: the development of the Early Screening of Autistic Traits Questionnaire (ESAT).

This article describes the development of a screening instrument for young children. Screening items were tested first in a non-selected population of children aged 8-20 months (n = 478). Then, parents of children with clinically diagnosed ASD (n = 153, average age 87 months) or ADHD (n = 76, average age 112 months) were asked to score the items retrospectively for when their child was 14 months old. A 14-item screening instrument, Early Screening of Autistic Traits (ESAT) which had maximal sensitivity and specificity for ASD was developed. The sensitivity of the ESAT was checked in an independent sample of 34 children aged 16-48 months clinically diagnosed with ASD. A 4-item version appears to be a promising prescreening instrument.

Asperger Syndrome↗

PubMed2006

Neuropsychological effects of risperidone in children with pervasive developmental disorders: a blinded discontinuation study.

OBJECTIVE: Little is known about the neuropsychological effects of risperidone in children with pervasive developmental disorders. METHOD: Twenty-four children (aged 5-17 years) with pervasive developmental disorders and co-morbid disruptive behavior who responded favorably to open-label treatment with risperidone as part of a previously described controlled discontinuation study completed two different computerized attention tasks at baseline, weeks 4, 8, and 24 of open-label treatment, and, at 8 weeks after random assignment to either placebo or risperidone. The primary efficacy measures were response latencies to visually presented stimuli requiring two different types of attention-controlled processing, i.e., focused and divided attention. RESULTS: About half of the clinical responders did not produce valid performance measures. These could be shown to be of younger mental age and less adaptive as measured by the Vineland Behavior Scales. For the valid task performers divided attention (serial search in working memory) was shown to regress in the placebo group (n = 7), while in the risperidone group (n = 7) there was further improvement. No such group difference was found for focused attention. CONCLUSIONS: The study suggests a beneficial effect of risperidone after several months of treatment, enhancing divided attention in children with pervasive developmental disorders.

Adolescent↗

PubMed2006

Atomoxetine for attention-deficit/hyperactivity disorder symptoms in children with pervasive developmental disorders: a pilot study.

OBJECTIVE: This pilot study examined the effects of atomoxetine on attention-deficit/hyperactivity disorder (ADHD) symptoms and autistic features in children with pervasive developmental disorders (PDD). METHOD: Twelve children (aged 6-14 years) with PDD accompanied by ADHD symptoms entered a 10-week open-label study with atomoxetine (1.19 +/- 0.41 mg/kg/day). Response was assessed by using parent and clinician rating scales with change in the ADHD-Rating Scale (ADHDRS) as primary outcome measure. RESULTS: Atomoxetine reduced ADHD-symptoms as measured by the ADHDRS (44% decrease vs. baseline, p < 0.003), the Conners' Parent Rating Scale-R:S (CPRS-R) (25% in the subscale "Cognitive Problems," p < 0.028; 32% in "Hyperactivity," p < 0.030; and 23% in "ADHD index," p < 0.023). We found a reduction of 21% (p = 0.071) for changes in the subscale "Hyperactivity" of the Aberrant Behavior Checklist (ABC). No change was found in any of the other ABC subscales, nor in the subscale "Oppositional" of the CPRS-R. Five patients (42%) discontinued because of side effects. Gastrointestinal symptoms, irritability, sleep problems, and fatigue were the most frequent side effects. CONCLUSIONS: These preliminary findings indicate that atomoxetine may be a promising new agent in the treatment of ADHD symptoms in children with PDD. However, children with PDD may have a higher vulnerability for some of the known side-effects of atomoxetine.

Adolescent↗

PubMed2006

Different treatment thresholds in non-Western children with behavioral problems.

OBJECTIVE: First, to investigate whether non-Western children in the Netherlands are less likely to be treated for behavioral problems than Western children; second, to examine whether discrepancies in treatment status are related to differences in level of problem behavior and impairment. METHOD: The study included 2,185 children of the four largest ethnic groups in the Netherlands, namely, 684 Dutch, 702 Moroccan, 434 Turkish, and 365 Surinamese children from grades three to five of elementary school. Teachers completed the Strengths and Difficulties Questionnaire and five DSM-IV items on externalizing problems. In addition, they provided information on the treatment status of the child. RESULTS: Moroccan boys displayed more problem behavior, Turkish boys less problem behavior, and Surinamese boys similar rates of problem behavior compared with Dutch boys. No difference in problem behavior was found between Western and non-Western girls. Adjusted for age, level of problem behavior, and impairment, Moroccan and Turkish children and Surinamese girls were less likely to receive treatment for problem behavior. CONCLUSIONS: The higher treatment thresholds of non-Western children compared with Western children in the Netherlands could not be explained by differences in level of problem behavior or impairment. Detection of behavioral problems in non-Western children should receive more attention.

Behavioral Symptoms↗

PubMed2006

Psychiatric morbidity in children with medically unexplained chronic pain: diagnosis from the pediatrician's perspective.

CONTEXT: There is very little general evidence to support the clinical management, particularly diagnosis, of medically unexplained chronic pain (UCP) in children. OBJECTIVE: We sought to assess in children with UCP if clinical characteristics held important by general pediatricians help to accurately diagnose psychiatric morbidity and, alternatively, if the same can be achieved using dedicated questionnaires. METHODS: We used a cross-sectional diagnostic study in a pediatric outpatient clinic of a university hospital. Our participants were 134 patients, aged 8 to 18 years, who were referred for UCP. Performed were (1) diagnostic test reflecting the pediatricians' choice of clinical characteristics and (2) selected questionnaires. Classification was performed according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, by a child psychiatrist using the Diagnostic Interview Schedule for Children-Parent Version IV and the Semi-structured Clinical Interview for Children and Adolescents. Results were analyzed by logistic regression. RESULTS: Psychiatric morbidity was present in 80 of the children. A minority had a medical explanation for the pain (15% definite, 17% probable). The clinical diagnostic model included age, social-problem indicators, family structure, parental somatization, and school problems. In the quintile of children in whom this model predicted the highest risk, 93% indeed had psychiatric morbidity at reference testing. In the quintile with the lowest predicted risk, indeed only 27% had psychiatric morbidity. The Dutch Personality Inventory for Youth and the Child Behavior Checklist matched the pediatricians' choice of clinical characteristics. In the quintile of children with the highest predicted risk based on these questionnaires, 89% had psychiatric morbidity. In the quintile with the lowest predicted risk, only 15% had psychiatric morbidity. CONCLUSIONS: A pediatrician-chosen set of clinical characteristics of children with UCP proves useful in diagnosing psychiatric morbidity. Using selected questionnaire screening yields similar results.

Adolescent↗

PubMed2005

DAT1, DRD4, and DRD5 polymorphisms are not associated with ADHD in Dutch families.

Recent meta-analyses have indicated that the dopamine transporter gene (DAT1) and the dopamine receptor genes D4 (DRD4) and D5 (DRD5) are associated with attention-deficit hyperactivity disorder (ADHD), although single studies frequently failed to show significant association. In a family-based sample of 236 Dutch children with ADHD, we have investigated the previously described variable number of tandem repeat (VNTR) polymorphisms and two additional microsatellites at the DAT1 and DRD4 loci. DRD5 was investigated using the microsatellite that was previously found to be associated. Transmission disequilibrium tests (TDTs) did not show preferential transmission of alleles or two-marker haplotypes to affected offspring. These data suggest that DAT1, DRD4, and DRD5 do not contribute substantially to ADHD in the Dutch population.

Alleles↗

PubMed2005

Disentangling deficits in adults with attention-deficit/hyperactivity disorder.

CONTEXT: A lack of inhibitory control has been suggested to be the core deficit in attention-deficit/hyperactivity disorder (ADHD), especially in adults. This means that a primary deficit in inhibition mediates a cascade of secondary deficits in other executive functions, such as attention. Impaired stopping has been claimed to support the inhibition hypothesis. However, executive functions such as inhibition and attention are hard to disentangle. OBJECTIVE: To use event-related potentials in adult patients with ADHD to show that impaired stopping is associated with abnormalities of attention. DESIGN: The stop signal task was presented to 24 adults with ADHD combined subtype and 24 controls. Stop event-related potentials are distorted by overlap from event-related potentials to other stimuli in close temporal proximity, but we applied a method (Adjar level 2) to effectively remove this overlap. RESULTS: In line with an inhibitory control deficit, the stop signal reaction time was longer in adults with ADHD (F(1,46) = 7.12, P<.01) whereas there was no significant difference for go stimulus reaction time. Overlap-free stop event-related potentials revealed smaller stop P3s in adults with ADHD (F(1,44) = 4.20, P<.05). In children with ADHD, this has been interpreted to reflect deficient inhibitory control. However, controls were also found to have larger early responses in the auditory cortex (N1) when stop signals resulted in successful stops, relative to failed stops, signifying increased attention (F(1,23) = 11.88, P<.01). This difference was completely absent in adults with ADHD. CONCLUSIONS: Disturbed attentional processing of the stop signal contributed to impaired stopping in adults with ADHD. This finding may have implications for treatment.

Adolescent↗

PubMed2005

The effects of prenatal stress on temperament and problem behavior of 27-month-old toddlers.

AIM: To examine, in a prospective study, the influence of prenatal stress on infant temperament and problem behavior. METHOD: Self-report data on stress and anxiety, and levels of cortisol in saliva were collected from nulli-parous women during pregnancy. Temperament of the child was measured at 27 months by parent report on the Infant Characteristics Questionnaire. Behavior of the child was assessed by direct observation during the administration of the Bayley Scales of Development 2-30, and by parent report on the Child Behavior Checklist 2-3. RESULTS: Complete data were available for 103 healthy toddlers. Logistic regression analyses were performed and results were adjusted for possible prenatal, perinatal and postnatal confounders. Perceived stress during pregnancy was a predictor of lower levels of restless/disruptive temperament (OR=0.77), more total behavioral problems (OR=1.17), and more externalizing behavioral problems (OR=1.12) in 2-year-olds. Fear of bearing a handicapped child was a predictor of higher levels of restless/disruptive temperament (OR=1.39) and more attention regulation problems in toddlers (OR=1.46). CONCLUSIONS: Increased levels of maternal prenatal stress appear to be associated with temperamental and behavioral problems in toddlers.

Child Behavior Disorders↗

PubMed2005

Physiological stress reactivity in human pregnancy--a review.

Prenatal maternal stress has been found to have long-lasting effects on the behavioral and physiological development of the offspring. These programming effects on the fetus would be physiologically mediated through heightened and/or abnormal activity of the maternal sympathetic-adrenal-medullary system (SAM) and especially of her hypothalamic-pituitary-adrenocortical axis (HPA-axis). The abnormalities in maternal physiology could be present in her basal functioning, but also in her physiological reactivity to stressors, which constitutes the topic of this paper. This article reviews studies that have used laboratory challenges to study physiological stress reactivity in pregnant women. It concentrates on stress tests designed to produce pain or discomfort, or cognitive and psychological stress, and that assess changes in blood pressure, heart rate and/or cortisol as reactivity measures. The general conclusion is that physiological stress reactivity appears to be dampened during pregnancy. Nonetheless, the physiological responses to laboratory challenges are clearly present and display enough inter-individual variability to enable the study of links between responsivity patterns, psychosocial variables, fetal behavior, pregnancy outcome and offspring development. This paper also looks into the methodological limitations present in the reviewed studies. Options for sound design of stress test protocols are discussed and recommendations for future studies are presented. These methodological points are general and can therefore also be of use for researchers studying human stress reactivity in other populations and ages.

Animals↗

PubMed2005

Prenatal stress and children's cortisol reaction to the first day of school.

Maternal prenatal stress has been found to be related to over-activity and/or dysregulation of the HPA-system in the offspring. These effects are more readily apparent in response to novel situations. The aim of the present report was to examine whether pregnancy stress predicted HPA-axis reactions of children to the first day of school after the summer break. Children of mothers with more prenatal stress were compared to those of mothers with less stress. Habituation was studied by comparisons between the first school day and a second school day a week later. Finally, cortisol levels at school were compared to those of a weekend day. The participants were 29 mother-child pairs (20 girls and nine boys, mean age 5.31 years, SD = 0.50). The children's cortisol levels were determined in saliva. Multilevel analysis (hierarchical linear modelling) was used to analyze the data. Both prenatal cortisol and pregnancy anxiety were related to the children's cortisol levels as a reaction to the first school day. Children whose mothers had higher levels of morning cortisol during pregnancy, and more fear of bearing a handicapped child showed higher levels of cortisol on school days. In addition, the circadian rhythm of cortisol on school days appeared to have a steeper slope as compared to that of the circadian curve on a weekend day.

Adaptation, Physiological↗

PubMed2005

Cortisol awakening response in pregnant women.

In this study, basal saliva cortisol was determined in women at 32 weeks of pregnancy and again at 9 months post-partum. During pregnancy, the cortisol levels of the 119 subjects were found to be elevated, with noon and evening levels more than twice as high as during the non-pregnant state. Despite the hypercortisolism, the cortisol awakening response was still present during pregnancy. Although the absolute mean increase in cortisol at 30 min post-awakening was larger during pregnancy, the relative mean increase was around 40% of the awakening level in both cases. The cortisol awakening response was not correlated between pregnancy and the post-partum, showing a lack of stability over the 11-month period. Finally, both in the pregnant and non-pregnant states, the magnitude of the cortisol awakening response was not related to time of awakening, nor to anticipation of a working vs. non-working day. In conclusion, the free cortisol awakening response is present during pregnancy, and is potentially a useful marker to study the association between prenatal psychosocial stress and offspring development.

Circadian Rhythm↗