Psychische Erkrankungen im Kindes- und Jugendalter und ihre Auswirkungen auf das Erwachsenwerden

Entwicklungsprozesse haben für die Entstehung und den Verlauf kinder- und jugendpsychiatrischer Störungen eine große Bedeutung. So manifestieren sich einige erst in bestimmten Altersphasen oder nehmen in der Häufigkeit mit zunehmender Reife wieder ab. Viele Entwicklungsverläufe reichen aber auch bis in das Erwachsenenalter hinein. Der vorliegende Artikel stellt zunächst eine Klassifikation kinder- und jugendpsychiatrischer Störungen in Abhängigkeit distinkter Entwicklungs- und Verlaufsaspekte dar. Anhand von drei Störungsbildern werden exemplarisch verschiedene Entwicklungsverläufe skizziert: Währen die Autismusspektrumsstörungen früh beginnen und oft zu lebenslangen Beeinträchtigungen führen, können Reifungsprozesse bei den Aufmerksamkeitsdefizit-/Hyperaktivitätsstörungen die Ausprägung der Symptomatik im Verlauf vermindern. Innerhalb der heterogenen Gruppe von Störungen des Sozialverhaltens bestehen erhebliche Unterschiede zwischen Entwicklungspfaden, die teilweise eine dauerhaft zunehmende Symptomatik von der Kindheit bis in das Erwachsenenalter hinein zeigen. Generell liegen z.T. bereits im Kindes- und Jugendalter übergreifende Beeinträchtigungen vor, die im Verlauf die Bewältigung notwendiger Entwicklungsaufgaben erschweren und zu umfangreichen Einschränkungen im Erwachsenenalter führen können. Es wird in diesem Zusammenhang die Bedeutung einer bereits im Kindes- und Jugendalter einsetzenden Therapie betont.

Young adolescents with autism show abnormal joint attention network: A gaze contingent fMRI study

Behavioral research has revealed deficits in the development of joint attention (JA) as one of the earliest signs of autism. While the neural basis of JA has been studied predominantly in adults, we recently demonstrated a protracted development of the brain networks supporting JA in typically developing children and adolescents. The present eye-tracking/fMRI study now extends these findings to adolescents with autism. Our results show that in adolescents with autism JA is subserved by abnormal activation patterns in brain areas related to social cognition abnormalities which are at the core of ASD including the STS and TPJ, despite behavioral maturation with no behavioral differences. Furthermore, in the autism group we observed increased neural activity in a network of social and emotional processing areas during interactions with their mother. Moreover, data indicated that less severely affected individuals with autism showed higher frontal activation associated with self-initiated interactions. Taken together, this study provides first-time data of JA in children/adolescents with autism incorporating the interactive character of JA, its reciprocity and motivational aspects. The observed functional differences in adolescents ASD suggest that persistent developmental differences in the neural processes underlying JA contribute to social interaction difficulties in ASD.

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Gaze-contingent fMRI task to study joint attention in a developmental sample with autism

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JA in the autism group elicited abnormal activation in social cognition related areas.

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The interaction partner's familiarity modulated brain activity in the autism group.

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In the autism group frontal activation is related to the severity of communication deficits.

Interaction of Pubertal Development and Metabolic Control in Adolescents with Type 1 Diabetes Mellitus

BACKGROUND

In T1DM, delayed pubertal development and reduced final height are associated with inadequate metabolic control.

OBJECTIVE

To assess whether T1DM affects pubertal growth spurt and whether metabolic control during puberty is gender-related.

METHODS

Using a large multicentre database, longitudinal data from 1294 patients were analysed. Inclusion criteria: complete records of height and HbA1c from the age of seven to 16 years. Exclusion criteria: other significant chronic diseases and medications, T1DM duration less than three months, and initial BMI < 3rd or >97th percentile.

RESULTS

Growth velocity (GV) was impaired with a significant reduction of peak GV by 1.2 cm in boys. HbA1c increase during male puberty was lower except for a period of 1.5 years. The highest HbA1c increase in boys coincided with maximum growth spurt. In girls, the highest HbA1c increase was observed during late puberty. Even though there is impaired GV, both sexes reach a height at 16 years of age which corresponds to the background population height.

CONCLUSION

Worsening of metabolic control is sex-discordant and associated with gender-specific alterations of GV. However, the vast majority of boys and girls with T1DM seems to reach normal height at the age of 16 years.

Diabetes in Patients with ß-thalassemia or other Hemoglobinopathies - Analysis from the DPV Database

Background: Diabetes mellitus is a common endocrinopathy in patients with thalassemia major, but the occurrence of hemoglobinopathies is rare in Germany and Western Europe. The longitudinal German-Austrian DPV (Diabetes Patienten Verlaufsdokumentation) registry allows a comprehensive characterization of this group of patients. Patients/methods: Patients from the DPV-registry aged<30 years with thalassemia major or other hemoglobinopathies were compared to patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) using the statistical software SAS 9.4. Results: 94 patients (0.13% of patients) with hemoglobinopathies are registered in DPV. 82.4% of 17 patients with thalassemia major, 100% of 12 patients with sickle cell disease (SCD) and >90% of 65 patients with other hemoglobinopathies receive insulin treatment. In the majority of patients with thalassemia major, hemosiderosis is documented. Patients with thalassemia major developed diabetes at a median age of 14.6 [IQR 8.4-18.0] years (9.0 years [5.3-12.5] in T1D; 18.7 years [14.2-25.6] in TD2; both p<0.01). They show high HbA1c/fructosamine levels and frequent hypoglycemia, reflecting poor metabolic control. Conclusion: Diabetes in thalassemia major is probably caused by hemosiderosis due to polytransfusion, while patients with SCD/thalassemia minor are most likely affected by T1D. The high rate of hypoglycemia in patients with ß-thalassemia major may be caused by liver fibrosis and a lack of hepatic glycogen stores.

Current practice of diabetes education in children and adolescents with type 1 diabetes in Germany and Austria: analysis based on the German/Austrian DPV database

BACKGROUND

Diabetes education of patients and/or parents is an essential part of diabetes care with effects on diabetes outcome. The objective of our study was to describe the current practice of diabetes education in Germany and Austria with regard to training frequency, patient age, migration background and diabetes therapy in a large cohort of pediatric patients with diabetes mellitus type 1 (T1DM).

METHODS

We analyzed data from pediatric T1DM patients with diabetes training in 2013 and complete data available for treatment year in the multicenter Diabetes Patienten Verlaufsdokumentation (DPV) registry using sas 9.4.

RESULTS

In 2013 21 871 pediatric patients with T1DM were documented [52.4% male, age: 12.70 (9.35-15.30) yr (median (interquartile range)], diabetes duration: 3.80 (1.45-7.00) yr, migration background: 21.4%, twice daily injections: 5.5%, multiple daily injections: 52.5%, insulin-pump therapy: 42%. Of these 32.31% were trained in 2013. Younger patients and their parents were trained more intensely and more frequently as inpatients compared with older patients (0-6 vs. 6-12 and 12-18 yr: teaching units: 13.07 vs. 12.05 and 9.79; inpatient: 79% vs. 72% and 70%). There was also a difference in training frequency with regard to migration background. Severe hypoglycemia or ketoacidosis resulted in intensification of training (4.0 vs. 2.0%; 7.8 vs. 3.1%). Centre-specific education tools were used frequently alone or in combination with published, standardized education programs.

CONCLUSION

Training frequency was highest in younger patients and during the first year of diabetes. Acute complications resulted in more frequent diabetes training, indicating that currently many education sessions take place in consequence to these complications.

Altered brain network integrity after childhood maltreatment: A structural connectomic DTI-study

Childhood maltreatment is associated with alterations in neural architecture that potentially put these children at increased risk for psychopathology. Alterations in white matter (WM) tracts have been reported, however no study to date has investigated WM connectivity in brain networks in maltreated children to quantify global and local abnormalities through graph theoretical analyses of DTI data. We aimed for a multilevel investigation examining the DTI-based structural connectome and its associations with basal cortisol levels of 25 children with documented maltreatment experiences before age 3, and 24 matched controls (age: 10.6 ± 1.75 years). On the global and lobar level, maltreated children showed significant reductions in global connectivity strength, local connectivity and increased path length, suggesting deviations from the small-world network architecture previously associated with psychopathology. Reductions in global connectivity were associated with placement instability, attenuated cortisol secretion and higher levels of internalizing and externalizing behaviours. Regional measures revealed lower connectivity strength especially in regions within the ventromedial prefrontal cortex (vMPFC) in maltreated children. These findings show that childhood maltreatment is associated with systemic global neurodevelopmental alterations in WM networks next to regional alterations in areas involved in the regulation of affect. These alterations in WM organization could underlie global functional deficits and multi-symptom patterns frequently observed in children with maltreatment experiences. Hum Brain Mapp 38:855-868, 2017. © 2016 Wiley Periodicals, Inc.

Look into my eyes: Investigating joint attention using interactive eye-tracking and fMRI in a developmental sample

Joint attention, the shared attentional focus of at least two people on a third significant object, is one of the earliest steps in social development and an essential aspect of reciprocal interaction. However, the neural basis of joint attention (JA) in the course of development is completely unknown. The present study made use of an interactive eye-tracking paradigm in order to examine the developmental trajectories of JA and the influence of a familiar interaction partner during the social encounter. Our results show that across children and adolescents JA elicits a similar network of "social brain" areas as well as attention and motor control associated areas as in adults. While other-initiated JA particularly recruited visual, attention and social processing areas, self-initiated JA specifically activated areas related to social cognition, decision-making, emotions and motivational/reward processes highlighting the rewarding character of self-initiated JA. Activation was further enhanced during self-initiated JA with a familiar interaction partner. With respect to developmental effects, activation of the precuneus declined from childhood to adolescence and additionally shifted from a general involvement in JA towards a more specific involvement for self-initiated JA. Similarly, the temporoparietal junction (TPJ) was broadly involved in JA in children and more specialized for self-initiated JA in adolescents. Taken together, this study provides first-time data on the developmental trajectories of JA and the effect of a familiar interaction partner incorporating the interactive character of JA, its reciprocity and motivational aspects.

Effects of serotonin depletion on punishment processing in the orbitofrontal and anterior cingulate cortices of healthy women

Diminished synthesis of the neurotransmitter serotonin (5-HT) has been linked to disrupted impulse control in aversive contexts. However, the neural correlates underlying a serotonergic modulation of female impulsivity remain unclear. The present study investigated punishment-induced inhibition in healthy young women. Eighteen healthy female subjects (aged 20-31) participated in a double-blinded, counterbalanced, placebo-controlled, within subjects, repeated measures study. They were assessed on two randomly assigned occasions that were controlled for menstrual cycle phase. In a randomized order, one day, acute tryptophan depletion (ATD) was used to reduce 5-HT synthesis in the brain. On the other day, participants received a tryptophan-balanced amino acid load (BAL) as a control condition. Three hours after administration of ATD/BAL, neural activity was recorded during a modified Go/No-Go task implementing reward or punishment processes using functional magnetic resonance imaging (fMRI). Neural activation during No-Go trials in punishment conditions after BAL versus ATD administration correlated positively with the magnitude of central 5-HT depletion in the ventral and subgenual anterior cingulate cortices (ACC). Furthermore, neural activation in the medial orbitofrontal cortex (mOFC) and the dorsal ACC correlated positively with trait impulsivity. The results indicate reduced neural sensitivity to punishment after short-term depletion of 5-HT in brain areas related to emotion regulation (subgenual ACC) increasing with depletion magnitude and in brain areas related to appraisal and expression of emotions (mOFC and dorsal ACC), increasing with trait impulsivity. This suggests a serotonergic modulation of neural circuits related to emotion regulation, impulsive behavior, and punishment processing in females.

Treatment of young patients with HNF1A mutations (HNF1A-MODY)

AIM

Children and adolescents with a molecular diagnosis of HNF1A-MODY should be treated with oral sulfonylurea according to current International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines.

METHODS

We surveyed the German-Austrian DPV database of 50 043 people and included 114 patients with a confirmed molecular-genetic diagnosis of HNF1A mutation and diabetes onset at below age 18 years. We analysed hypoglycaemic episodes, metabolic control (HbA1c ) and other clinical variables according to treatment groups.

RESULTS

People with HNF1A-MODY were included and analysed according to treatment with insulin alone (n = 34), sulfonylurea (n = 30), meglitinides (n = 22) or lifestyle (n = 28). In those receiving any drug treatment (n = 86), severe hypoglycaemia did not occur with meglitinide and was highest (at 3.6 events per 100 patient-years) with insulin. HbA1c was highest with insulin treatment (insulin = 58 mmol/mol, 7.5%; sulfonylurea = 55 mmol/mol, 7.2%; meglitinides = 52 mmol/mol, 6.9%; P = 0.008), whereas weight (BMI SD score), serum lipids and blood pressure were not different.

CONCLUSIONS

Of note, 40% of people with HNF1A-MODY and medical treatment were receiving insulin alone and thus were not being treated in line with up-to-date International Society for Pediatric and Adolescent Diabetes/International Diabetes Federation guidelines, despite insulin treatment being associated with worse metabolic control and the risk of hypoglycaemia. The unlicensed use of oral drugs in patients below age 18 years and adherence by both doctors and patients to the initial insulin treatment might contribute to this finding.

Deciphering the genetic basis of microcystin tolerance

BACKGROUND

Cyanobacteria constitute a serious threat to freshwater ecosystems by producing toxic secondary metabolites, e.g. microcystins. These microcystins have been shown to harm livestock, pets and humans and to affect ecosystem service and functioning. Cyanobacterial blooms are increasing worldwide in intensity and frequency due to eutrophication and global warming. However, Daphnia, the main grazer of planktonic algae and cyanobacteria, has been shown to be able to suppress bloom-forming cyanobacteria and to adapt to cyanobacteria that produce microcystins. Since Daphnia's genome was published only recently, it is now possible to elucidate the underlying molecular mechanisms of microcystin tolerance of Daphnia.

RESULTS

Daphnia magna was fed with either a cyanobacterial strain that produces microcystins or its genetically engineered microcystin knock-out mutant. Thus, it was possible to distinguish between effects due to the ingestion of cyanobacteria and effects caused specifically by microcystins. By using RNAseq the differentially expressed genes between the different treatments were analyzed and affected KOG-categories were calculated. Here we show that the expression of transporter genes in Daphnia was regulated as a specific response to microcystins. Subsequent qPCR and dietary supplementation with pure microcystin confirmed that the regulation of transporter gene expression was correlated with the tolerance of several Daphnia clones.

CONCLUSIONS

Here, we were able to identify new candidate genes that specifically respond to microcystins by separating cyanobacterial effects from microcystin effects. The involvement of these candidate genes in tolerance to microcystins was validated by correlating the difference in transporter gene expression with clonal tolerance. Thus, the prevention of microcystin uptake most probably constitutes a key mechanism in the development of tolerance and adaptation of Daphnia. With the availability of clear candidate genes, future investigations examining the process of local adaptation of Daphnia populations to microcystins are now possible.

The role of the right temporoparietal junction in attention and social interaction as revealed by ALE meta-analysis

The right temporoparietal junction (rTPJ) is frequently associated with different capacities that to shift attention to unexpected stimuli (reorienting of attention) and to understand others' (false) mental state [theory of mind (ToM), typically represented by false belief tasks]. Competing hypotheses either suggest the rTPJ representing a unitary region involved in separate cognitive functions or consisting of subregions subserving distinct processes. We conducted activation likelihood estimation (ALE) meta-analyses to test these hypotheses. A conjunction analysis across ALE meta-analyses delineating regions consistently recruited by reorienting of attention and false belief studies revealed the anterior rTPJ, suggesting an overarching role of this specific region. Moreover, the anatomical difference analysis unravelled the posterior rTPJ as higher converging in false belief compared with reorienting of attention tasks. This supports the concept of an exclusive role of the posterior rTPJ in the social domain. These results were complemented by meta-analytic connectivity mapping (MACM) and resting-state functional connectivity (RSFC) analysis to investigate whole-brain connectivity patterns in task-constrained and task-free brain states. This allowed for detailing the functional separation of the anterior and posterior rTPJ. The combination of MACM and RSFC mapping showed that the posterior rTPJ has connectivity patterns with typical ToM regions, whereas the anterior part of rTPJ co-activates with the attentional network. Taken together, our data suggest that rTPJ contains two functionally fractionated subregions: while posterior rTPJ seems exclusively involved in the social domain, anterior rTPJ is involved in both, attention and ToM, conceivably indicating an attentional shifting role of this region.

Genome-wide quantitative analysis of histone H3 lysine 4 trimethylation in wild house mouse liver: environmental change causes epigenetic plasticity

In mammals, exposure to toxic or disease-causing environments can change epigenetic marks that are inherited independently of the intrauterine environment. Such inheritance of molecular phenotypes may be adaptive. However, studies demonstrating molecular evidence for epigenetic inheritance have so far relied on extreme treatments, and are confined to inbred animals. We therefore investigated whether epigenomic changes could be detected after a non-drastic change in the environment of an outbred organism. We kept two populations of wild-caught house mice (Mus musculus domesticus) for several generations in semi-natural enclosures on either standard diet and light cycle, or on an energy-enriched diet with longer daylight to simulate summer. As epigenetic marker for active chromatin we quantified genome-wide histone-3 lysine-4 trimethylation (H3K4me3) from liver samples by chromatin immunoprecipitation and high-throughput sequencing as well as by quantitative polymerase chain reaction. The treatment caused a significant increase of H3K4me3 at metabolic genes such as lipid and cholesterol regulators, monooxygenases, and a bile acid transporter. In addition, genes involved in immune processes, cell cycle, and transcription and translation processes were also differently marked. When we transferred young mice of both populations to cages and bred them under standard conditions, most of the H3K4me3 differences were lost. The few loci with stable H3K4me3 changes did not cluster in metabolic functional categories. This is, to our knowledge, the first quantitative study of an epigenetic marker in an outbred mammalian organism. We demonstrate genome-wide epigenetic plasticity in response to a realistic environmental stimulus. In contrast to disease models, the bulk of the epigenomic changes we observed were not heritable.

Frequent mutations in chromatin-remodelling genes in pulmonary carcinoids

Pulmonary carcinoids are rare neuroendocrine tumours of the lung. The molecular alterations underlying the pathogenesis of these tumours have not been systematically studied so far. Here we perform gene copy number analysis (n=54), genome/exome (n=44) and transcriptome (n=69) sequencing of pulmonary carcinoids and observe frequent mutations in chromatin-remodelling genes. Covalent histone modifiers and subunits of the SWI/SNF complex are mutated in 40 and 22.2% of the cases, respectively, with MEN1, PSIP1 and ARID1A being recurrently affected. In contrast to small-cell lung cancer and large-cell neuroendocrine lung tumours, TP53 and RB1 mutations are rare events, suggesting that pulmonary carcinoids are not early progenitor lesions of the highly aggressive lung neuroendocrine tumours but arise through independent cellular mechanisms. These data also suggest that inactivation of chromatin-remodelling genes is sufficient to drive transformation in pulmonary carcinoids.

Somatropin treatment of spinal muscular atrophy: a placebo-controlled, double-blind crossover pilot study

In preclinical studies growth hormone and its primary mediator IGF-1 have shown potential to increase muscle mass and strength. A single patient with spinal muscular atrophy reported benefit after compassionate use of growth hormone. Therefore we evaluated the efficacy and safety of growth hormone treatment for spinal muscular atrophy in a multicenter, randomised, double-blind, placebo-controlled, crossover pilot trial. Patients (n = 19) with type II/III spinal muscular atrophy were randomised to receive either somatropin (0.03 mg/kg/day) or placebo subcutaneously for 3 months, followed by a 2-month wash-out phase before 3 months of treatment with the contrary remedy. Changes in upper limb muscle strength (megascore for elbow flexion and hand-grip in Newton) were assessed by hand-held myometry as the primary measure of outcome. Secondary outcome measures included lower limb muscle strength, motor function using the Hammersmith Functional Motor Scale and other functional tests for motor function and pulmonary function. Somatropin treatment did not significantly affect upper limb muscle strength (point estimate mean: 0.08 N, 95% confidence interval (CI:-3.79;3.95, p = 0.965), lower limb muscle strength (point estimate mean: 2.23 N, CI:-2.19;6.63, p = 0.302) or muscle and pulmonary function. Side effects occurring during somatropin treatment corresponded with well-known side effects of growth hormone substitution in patients with growth hormone deficiency. In this pilot study, growth hormone treatment did not improve muscle strength or function in patients with spinal muscular atrophy type II/III.

Fast isogenic mapping-by-sequencing of ethyl methanesulfonate-induced mutant bulks

Mapping-by-sequencing (or SHOREmapping) has revitalized the powerful concept of forward genetic screens in plants. However, as in conventional genetic mapping approaches, mapping-by-sequencing requires phenotyping of mapping populations established from crosses between two diverged accessions. In addition to the segregation of the focal phenotype, this introduces natural phenotypic variation, which can interfere with the recognition of quantitative phenotypes. Here, we demonstrate how mapping-by-sequencing and candidate gene identification can be performed within the same genetic background using only mutagen-induced changes as segregating markers. Using a previously unknown suppressor of mutants of like heterochromatin protein1 (lhp1), which in its functional form is involved in chromatin-mediated gene repression, we identified three closely linked ethyl methanesulfonate-induced changes as putative candidates. In order to assess allele frequency differences between such closely linked mutations, we introduced deep candidate resequencing using the new Ion Torrent Personal Genome Machine sequencing platform to our mutant identification pipeline and thereby reduced the number of causal candidate mutations to only one. Genetic analysis of two independent additional alleles confirmed that this mutation was causal for the suppression of lhp1.

Development of neural correlates of empathy from childhood to early adulthood: an fMRI study in boys and adult men

Although empathy is rooted early in life, the ability to understand and share the emotions of others continues to develop after childhood. Here, we aimed at exploring developmental changes in the neural mechanisms underlying empathy from childhood to early adulthood. Using functional magnetic resonance imaging, 47 healthy male subjects aged 8-27 years were investigated during an explicit empathy task. Emotional faces were presented and participants were either asked to infer the emotional state from the face (other-task) or to judge their own emotional response to the face (self-task). A perceptual decision on the width of faces was used as a control condition. Age-related activity increases were observed in the fusiform gyrus and inferior frontal gyrus, depending on whether subjects attributed emotions to self or other. During the self-task, activity in the right precuneus and right intraparietal sulcus decreased as a function of age. No age-related differences were observed in behavioral performance measures. Increased activity in the fusiform gyrus and in the frontal component of the human mirror neuron system with increasing age may be explained by greater experience and expertise accumulated during socio-emotional interactions. Greater recruitment of right parietal structures in younger as compared to older subjects might reflect developmental differences in the cognitive strategies to infer one's own emotional response. This study is the first to show developmental changes in the neural mechanisms supporting empathy. Our findings may have important implications for the development of novel therapeutic interventions in clinical conditions characterized by empathy deficits, such as autism spectrum disorder.

[Attention deficit hyperactivity syndrome throughout the life span]

Attention deficit hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders in children. ADHD is often chronic persisting into adulthood in about 60% of patients. The disorder is frequently associated with co-occurring disruptive, anxiety, mood and personality disorders as well as substance abuse. The diagnosis of ADHD has to be based on careful assessment of symptoms and impairments in the different phases of life. Recent neuroimaging and genetic data support the neurobiological basis of the disorder. Multimodal treatment options including stimulants, antidepressants and behavioral therapy play a fundamental role in the management of ADHD across the life span.

Exploring the genetic link between RLS and ADHD

Attention deficit/hyperactivity disorder (ADHD) is a highly heritable neurodevelopmental disorder of childhood onset. Clinical and biological evidence points to shared common central nervous system (CNS) pathology of ADHD and restless legs syndrome (RLS). It was hypothesized that variants previously found to be associated with RLS in two large genome-wide association studies (GWA), will also be associated with ADHD. SNPs located in MEIS1 (rs2300478), BTBD9 (rs9296249, rs3923809, rs6923737), and MAP2K5 (rs12593813, rs4489954) as well as three SNPs tagging the identified haplotype in MEIS1 (rs6710341, rs12469063, rs4544423) were genotyped in a well characterized German sample of 224 families comprising one or more affected sibs (386 children) and both parents. We found no evidence for preferential transmission of the hypothesized variants to ADHD. Subsequent analyses elicited nominal significant association with haplotypes consisting of the three SNPs in BTBD9 (chi2 = 14.8, df = 7, nominal p = 0.039). According to exploratory post hoc analyses, the major contribution to this finding came from the A-A-A-haplotype with a haplotype-wise nominal p-value of 0.009. However, this result did not withstand correction for multiple testing. In view of our results, RLS risk alleles may have a lower effect on ADHD than on RLS or may not be involved in ADHD. The negative findings may additionally result from genetic heterogeneity of ADHD, i.e. risk alleles for RLS may only be relevant for certain subtypes of ADHD. Genes relevant to RLS remain interesting candidates for ADHD; particularly BTBD9 needs further study, as it has been related to iron storage, a potential pathophysiological link between RLS and certain subtypes of ADHD.

Neuropsychological and behavioural disinhibition in adult ADHD compared to borderline personality disorder

BACKGROUND

Although attention-deficit/hyperactivity disorder (ADHD) is thought to be an inhibitory disorder, the question remains of how specific the inhibitory deficit is in adults and whether it distinguishes ADHD from borderline personality disorder (BPD), with which it shares several clinical features, particularly impulsiveness.

METHOD

The study assessed various motor and cognitive inhibitory functions (inhibition of prepotent, ongoing and interfering responses) in addition to working memory in adult ADHD patients with and without BPD, compared to subjects with BPD alone and controls. In addition, questionnaire data on various aspects of impulsiveness and anger regulation were assessed in all groups.

RESULTS

ADHD patients performed worse than BPD individuals and controls in two inhibitory tasks: the stop signal task and the conflict module of the Attentional Network Task (ANT). In addition, they exhibited longer reaction times (RTs) and higher intra-individual variance in nearly all attentional tasks. The co-morbid group exhibited poor performance on the stop signal task but not on the conflict task. The BPD group barely differed from controls in neuropsychological performance but overlapped with ADHD in some behavioural problems, although they were less severe on the whole.

CONCLUSIONS

Impaired inhibition is a core feature in adults with ADHD. In addition, slow RTs and high intra-individual variance in performance may reflect deficits in the regulation of activation and effort in ADHD patients. ADHD and BPD share some symptoms of behavioural dysregulation without common cognitive deficits, at least in the attentional realm.

Association and linkage of allelic variants of the dopamine transporter gene in ADHD

Previously, we had reported a genome-wide scan for attention-deficit/hyperactivity disorder (ADHD) in 102 families with affected sibs of German ancestry; the highest multipoint LOD score of 4.75 was obtained on chromosome 5p13 (parametric HLOD analysis under a dominant model) near the dopamine transporter gene (DAT1). We genotyped 30 single nucleotide polymorphisms (SNPs) in this candidate gene and its 5' region in 329 families (including the 102 initial families) with 523 affected offspring. We found that (1) SNP rs463379 was significantly associated with ADHD upon correction for multiple testing (P=0.0046); (2) the global P-value for association of haplotypes was significant for block two upon correction for all (n=3) tested blocks (P=0.0048); (3) within block two we detected a nominal P=0.000034 for one specific marker combination. This CGC haplotype showed relative risks of 1.95 and 2.43 for heterozygous and homozygous carriers, respectively; and (4) finally, our linkage data and the genotype-IBD sharing test (GIST) suggest that genetic variation at the DAT1 locus explains our linkage peak and that rs463379 (P<0.05) is the only SNP of the above haplotype that contributed to the linkage signal. In sum, we have accumulated evidence that genetic variation at the DAT1 locus underlies our ADHD linkage peak on chromosome 5; additionally solid association for a single SNP and a haplotype were shown. Future studies are required to assess if variation at this locus also explains other positive linkage results obtained for chromosome 5p.

Attentional functions in children and adolescents with attention-deficit/hyperactivity disorder with and without comorbid tic disorder

Although the coexistence of attention-deficit/hyperactivity disorder (ADHD) and tic disorder (TD) is common, the nature of association is yet not fully understood. Thus, the aim of the present study was to explore attentional dysfunction in children with pure ADHD compared to children with comorbid ADHD + TD. Three groups of 20 children each, aged 8-15 years with either ADHD, ADHD + chronic tic disorder or Tourette syndrome (ADHD + TD) and a healthy control group were compared in their performance on three computerized attention tasks. Tasks of sustained attention, selective attention and interference control were employed. In addition, parental ratings of ADHD symptom severity and behaviour problems were obtained. Both clinical groups were rated as equally inattentive, however, externalising symptoms were more severe in the ADHD group. Objective measures of attentional performance revealed differences between the groups: whereas the ADHD group was markedly impaired in sustaining attention and selective attention/inhibitory control, the ADHD + TD group only showed marginal deficits in selective attention/inhibitory control. Possible explanations for the superior performance of the comorbid group are discussed: In particular, the results may indicate that in some patients, the tic disorder produces behavioural symptoms of ADHD, but not the broad neurocognitive deficits that usually are associated with ADHD. Alternatively, compensatory neural mechanisms of TD patients may result in a better neuropsychological performance of comorbid patients relative to patients suffering from pure ADHD.

Long-term behavior and quality of life after corrective cardiac surgery in infancy for tetralogy of Fallot or ventricular septal defect

The objective of this study was to evaluate behavior and quality of life in children after corrective cardiac surgery in infancy. Twenty cyanotic (tetralogy of Fallot) and 20 acyanotic children (ventricular septal defect), operated at a mean age of 0.7 years with deep hypothermic circulatory arrest (DHCA) and low-flow cardiopulmonary bypass (CPB), were assessed at a mean age of 7.4 years by the Child Behavior Checklist (CBCL) and the German KINDL. Test results were related to perioperative and neurodevelopmental outcome. Compared to healthy children and not significantly different between the groups, internalizing and externalizing problems were elevated, school performance and total competence were reduced, and self- and parent-reported quality of life was not reduced. Parent-reported problems and reduced physical status were correlated with longer durations of DHCA and CPB. Internalizing and externalizing problems, reduced school competence, and reduced self-esteem were associated with reduced endurance capacity. Externalizing problems were related to reduced gross motor function. Poor school competence was related to reduced intelligence and academic achievement. Children with preoperative hypoxemia in infancy due to cyanotic cardiac defects are not at significantly higher risk for behavioral problems and reduced quality of life than those with acyanotic heart defects. The risk of long-term psychosocial maladjustment after corrective surgery in infancy is increased compared to that for normal children and related to the presence of neurodevelopmental dysfunction.

No evidence for preferential transmission of common valine allele of the Val66Met polymorphism of the brain-derived neurotrophic factor gene (BDNF) in ADHD

Attention deficit/hyperactivity disorder (ADHD) is a highly heritable common neurodevelopmental disorder with onset in childhood. A coding SNP (rs6265, Val66Met) of the brain-derived neurotrophic factor gene (BDNF) has recently been associated with ADHD. More specifically, paternal over-transmission of the common Val66 allele to affected children had been observed. We aimed to confirm these findings in a large, sufficiently powered, and well characterized German ADHD family sample. The Val66Met polymorphism of BDNF was genotyped in 294 families comprising one or more affected sibs (468 children). Contrary to previous reports, we did not observe over-transmission of the common Val66 allele, from either parent to affected children. We did not find support for an involvement of the Val66 allele of the Val66Met polymorphism of BDNF in the pathogenesis of ADHD in our sample.

Family-based association study of serotonergic candidate genes and attention-deficit/hyperactivity disorder in a German sample

Alterations in the serotonergic pathway have been implicated in the pathogenesis of attention-deficit/hyperactivity disorder (ADHD). The aim of this study was to investigate seven genetic variants in three genes (serotonin transporter (5-HTT), serotonin receptor 1B (5-HTR1B) and serotonin receptor 2A (5-HTR2A)), which have previously been shown to be associated with ADHD. The polymorphisms under investigation were the 5-HTTLPR, the VNTR in intron 2 and the 3'UTR SNP in 5-HTT, the 5-HTR1B variations 861G>C and 102T>C, and the 5-HTR2A variations His452Tyr and 1438G>A. We genotyped these variants in a sample of 102 families with 229 children with ADHD according to DSM-IV criteria. Among the affected children, 69% fulfilled criteria for the combined type, 27% for the predominantly inattentive type, and 4% for the predominantly hyperactive-impulsive type. Associations were tested by the pedigree transmission disequilibrium test (PDT). All investigated polymorphisms in serotonergic candidate genes showed no association to ADHD in our sample. Earlier studies of these polymorphisms had also shown inconsistent results, with some studies reporting significant associations and others demonstrating no association. This discordance between studies may reflect variation in patient ascertainment criteria, genetic heterogeneity, too low statistical power for the expected effects or false positive results in the initial reports. We cannot rule out the possibility that other variations in the investigated genes contribute to the etiology of ADHD.

A genome-wide scan for attention-deficit/hyperactivity disorder in 155 German sib-pairs

Three groups have previously performed genome scans in attention-deficit/hyperactivity disorder (ADHD); linkage to chromosome 5p13 was detected in all of the respective studies. In the current study, we performed a whole-genome scan with 102 German families with two or more offspring who currently fulfilled the diagnostic criteria for ADHD. Including subsequent fine mapping on chromosome 5p, a total of 523 markers were genotyped. The highest nonparametric multipoint LOD score of 2.59 (empirical genome-wide significance 0.1) was obtained for chromosome 5p at 17 cM (according to the Marshfield map). Subsequent analyses revealed (a) a higher LOD score of 3.37 at 39 cM for a quantitative severity score based on symptoms of inattention than for hyperactivity/impulsivity (LOD score of 1.11 at 59 cM), and (b) an HLOD of 4.75 (empirical genome-wide significance 0.001) based on a parametric model assuming dominant inheritance. The locus of the solute carrier 6A3 (SLC6A3; dopamine transporter 1; DAT1) localizes to 5p15.33; the gene has repeatedly been implicated in the etiology of ADHD. However, in our sample the DAT1 VNTR did not show association with ADHD. We additionally identified nominal evidence for linkage to chromosomes 6q, 7p, 9q, 11 q, 12q and 17p, which had also been identified in previous scans. Despite differences in ethnicity, ascertainment and phenotyping schemes, linkage results in ADHD appear remarkably consistent.

Transmission disequilibrium of polymorphic variants in the tryptophan hydroxylase-2 gene in attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder in childhood with substantial heritability. Pharmacological and molecular genetic studies as well as characterization of animal models have implicated serotonergic dysfunction in the pathophysiology of ADHD. Here, we investigated the effect of polymorphic variants in the gene of the tryptophan hydroxylase-2 (TPH2), the rate-limiting enzyme of serotonin (5-HT) synthesis in the brain, in children and adolescents with ADHD. We analyzed three single nucleotide polymorphisms (SNPs) in and downstream of the transcriptional control region of the TPH2 gene in 103 families with 225 affected children. Allelic association in families with more than one affected child was assessed using the pedigree disequilibrium test. Preferential transmissions were detected for the two SNPs in TPH2's regulatory region (rs4570625, P=0.049; rs11178997, P=0.034), but not for the third SNP in intron 2 (rs4565946, P=0.3517). Haplotype analysis revealed a strong trend of association between the regulatory region SNPs (rs4570625, rs11178997) and ADHD (P=0.064). Our results link potentially functional TPH2 variations to the pathophysiology of ADHD, and further support the relevance of 5-HT in disorders related to altered motor activity and cognitive processes.

Oculomotor inhibition in children with and without attention-deficit hyperactivity disorder (ADHD)

The aim of the present study was to distinguish between a general deficit in oculomotor control and a deficit restricted to inhibitory functions in children with attention deficit hyperactivity disorder (ADHD). In addition, we were interested in differentiating between a general inhibition deficit and deficient subfunctions of inhibition. We used a prosaccade task to measure general oculomotor abilities in 22 children with ADHD and in age- and gender-matched healthy controls. A fixation, an antisaccade and a countermanding saccade task were used to measure specific aspects of oculomotor inhibition. Two major results were obtained: First, our prosaccade task suggests similar saccadic response preparation and saccadic accuracy in the ADHD compared to the control children. Secondly, the fixation and the countermanding saccade task indicate deficits on measures of oculomotor inhibition in the ADHD group. While patients were specifically impaired in stopping an already initiated response or in suppressing exploratory saccades in a novel situation, inhibition of a prepotent response was not deficient. Our data thus indicate an underlying impairment in cognitive inhibition in ADHD that has been associated with prefrontal lobe functions. More specifically, as the anterior cingulate gyrus has been associated with the countermanding saccade task and group differences were most pronounced in this paradigm our data are in line with imaging data stressing the importance of this cortical structure in the pathophysiology of ADHD.

A retrospective study of SSRI treatment in adolescent anorexia nervosa: insufficient evidence for efficacy

Although selective-serotonin-reuptake-inhibitors (SSRI) have been of limited efficacy in the treatment of eating disorder psychopathology and comorbid symptoms of malnourished patients with anorexia nervosa (AN), there is recent data suggesting that SSRI may play a role in preventing relapse among weight-restored patients. Though some previous studies included patients in late adolescence, the vast majority of investigated subjects have been adults. The aim of our retrospective study was to assess the effects of SSRI treatment in partially weight-restored children and adolescents with AN. Thirty two females with AN (mean 14.5+/-1.4 years) were investigated three times during inpatient treatment and at 3- and 6-month follow-up for BMI, eating disorder psychopathology, depressive symptomology, and obsessive-compulsive symptomology. Medication history during inpatient and outpatient treatment was reconstructed at the 6-month follow-up. Nineteen patients received SSRI treatment, while 13 subjects were non-medicated. In comparison to the non-SSRI group, the SSRI group had similar BMI and obsessive-compulsive scores, but higher levels of core eating disorder psychopathology and depressive symptoms at the start of medication. Rates of re-admissions were similar in both groups (SSRI group: 36%, non-SSRI group: 31%, Phi: p=0.72). Repeated measures ANOVA revealed no significant group with time interactions for BMI-SDS (p=0.84), core eating disorder symptoms (ANIS, p=0.79), depression (DIKJ, p=0.75), and obsessive-compulsive (CY-BOCS, p=0.40) scores indicating minimal or no effects of SSRI medication on the course of these variables. In conclusion, our results challenge the efficacy of SSRI medication in the treatment of eating disorder psychopathology as well as depressive and obsessive-compulsive comorbidity in adolescent AN. Clinicians should be chary in prescribing SSRI in adolescent AN unless randomized controlled trials have proofed the benefit of these drugs.

Molecular genetic aspects of attention-deficit/hyperactivity disorder

Two genome wide scans, one of which was subsequently extended, have led to the identification of different chromosomal regions assumed to harbour genes underlying attention-deficit/hyperactivity disorder (ADHD). Some of these regions were also identified in patients with autism and/or dyslexia. The only region for which both studies detected a LOD score >1 was on chr 5p13 which is in the vicinity of the location of the candidate gene DAT1. The candidate gene approach has revealed the most robust and replicated findings for DRD4, DRD5, and DAT1 polymorphisms. Meanwhile interesting endophenotype studies have also been conducted suggesting a genetic basis for different diagnostic and therapeutic criteria. Animal studies for ADHD have investigated especially hyperactivity and have focused mainly on knockout and QTL designs. In knockout mice models the most promising results were obtained for genes of the dopaminergic pathway. QTL results in rodents suggest multiple loci underlying different forms of natural and induced hyperactivity. The molecular results mentioned above are presented and discussed in detail, thus providing both clinicians and geneticists with an overview of the current research status of this important child and adolescent psychiatric disorder.

Mutation screen of the brain derived neurotrophic factor gene (BDNF): identification of several genetic variants and association studies in patients with obesity, eating disorders, and attention-deficit/hyperactivity disorder

Several lines of evidence indicate an involvement of brain derived neurotrophic factor (BDNF) in body weight regulation and activity: heterozygous Bdnf knockout mice (Bdnf(+/-)) are hyperphagic, obese, and hyperactive; furthermore, central infusion of BDNF leads to severe, dose-dependent appetite suppression and weight loss in rats. We searched for the role of BDNF variants in obesity, eating disorders, and attention-deficit/hyperactivity disorder (ADHD). A mutation screen (SSCP and DHPLC) of the translated region of BDNF in 183 extremely obese children and adolescents and 187 underweight students was performed. Additionally, we genotyped two common polymorphisms (rs6265: p.V66M; c.-46C > T) in 118 patients with anorexia nervosa, 80 patients with bulimia nervosa, 88 patients with ADHD, and 96 normal weight controls. Three rare variants (c.5C > T: p.T2I; c.273G > A; c.*137A > G) and the known polymorphism (p.V66M) were identified. A role of the I2 allele in the etiology of obesity cannot be excluded. We found no association between p.V66M or the additionally genotyped variant c.-46C > T and obesity, ADHD or eating disorders. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html.