1
|
Nijmeijer JS, Arias-Vásquez A, Rommelse NNJ, Altink ME, Buschgens CJM, Fliers EA, Franke B, Minderaa RB, Sergeant JA, Buitelaar JK, Hoekstra PJ, Hartman CA. Quantitative Linkage for Autism Spectrum Disorders Symptoms in Attention-Deficit/Hyperactivity Disorder: Significant Locus on Chromosome 7q11. J Autism Dev Disord 2014; 44:1671-80. [DOI: 10.1007/s10803-014-2039-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
2
|
Altink ME, Rommelse NNJ, Slaats-Willemse DIE, Vásquez AA, Franke B, Buschgens CJM, Fliers EA, Faraone SV, Sergeant JA, Oosterlaan J, Buitelaar JK. The dopamine receptor D4 7-repeat allele influences neurocognitive functioning, but this effect is moderated by age and ADHD status: an exploratory study. World J Biol Psychiatry 2012; 13:293-305. [PMID: 22111665 DOI: 10.3109/15622975.2011.595822] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES Evidence suggests the involvement of the dopamine D4 receptor gene (DRD4) in the pathogenesis of ADHD, but the exact mechanism is not well understood. Earlier reports on the effects of DRD4 polymorphisms on neurocognitive and neuroimaging measures are inconsistent. This study investigated the functional consequences of the 7-repeat allele of DRD4 on neurocognitive endophenotypes of ADHD in the Dutch subsample of the International Multicenter ADHD Genetics study. METHODS Participants were 350 children (5-11.5 years) and adolescents (11.6-19 years) with ADHD and their 195 non-affected siblings. An overall measure of neuropsychological functioning was derived by principal component analysis from five neurocognitive and five motor tasks. The effects of DRD4 and age were examined using Linear Mixed Model analyses. RESULTS The analyses were stratified for affected and non-affected participants after finding a significant three-way interaction between ADHD status, age and the 7-repeat allele. Apart from a main effect of age, a significant interaction effect of age and DRD4 was found in non-affected but not in affected participants, with non-affected adolescent carriers of the 7-repeat allele showing worse neuropsychological performance. In addition, carrying the 7-repeat allele of DRD4 was related to a significantly worse performance on verbal working memory in non-affected siblings, independent of age. CONCLUSIONS These results might indicate that the effect of the DRD4 7-repeat allele on neuropsychological functioning is dependent on age and ADHD status.
Collapse
Affiliation(s)
- Marieke E Altink
- Department of Psychiatry, Radboud University Nijmegen Medical Center, Donders Institute for Brain, Cognition and Behavior, Nijmegen, The Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Arias-Vásquez A, Altink ME, Rommelse NNJ, Slaats-Willemse DIE, Buschgens CJM, Fliers EA, Faraone SV, Sergeant JA, Oosterlaan J, Franke B, Buitelaar JK. CDH13 is associated with working memory performance in attention deficit/hyperactivity disorder. Genes Brain Behav 2011; 10:844-51. [PMID: 21815997 DOI: 10.1111/j.1601-183x.2011.00724.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Different analytic strategies, including linkage, association and meta-analysis support a role of CDH13 in the susceptibility to attention deficit/hyperactivity disorder (ADHD). CDH13 codes for cadherin 13 (or H-cadherin), which is a member of a family of calcium-dependent cell-cell adhesion proteins and a regulator of neural cell growth. We tested the association between CDH13 on three executive functioning tasks that are promising endophenotypes of ADHD. An adjusted linear regression analysis was performed in 190 ADHD-affected Dutch probands of the IMAGE project. Three executive functions were examined: inhibition, verbal and visuo-spatial working memory (WM). We tested 2632 single nucleotide polymorphisms (SNPs) within CDH13 and 20 kb up- and downstream of the gene (capturing regulatory sequences). To adjust for multiple testing within the gene, we applied stringent permutation steps. Intronic SNP rs11150556 is associated with performance on the Verbal WM task. No other SNP showed gene-wide significance with any of the analyzed traits, but a 72-kb SNP block located 446 kb upstream of SNP rs111500556 showed suggestive evidence for association (P-value range 1.20E-03 to 1.73E-04) with performance in the same Verbal WM task. This study is the first to examine CDH13 and neurocognitive functioning. The mechanisms underlying the associations between CDH13 and the clinical phenotype of ADHD and verbal WM are still unknown. As such, our study may be viewed as exploratory, with the results presented providing interesting hypotheses for further testing.
Collapse
Affiliation(s)
- A Arias-Vásquez
- Department of Psychiatry (966), Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Fliers EA, Franke B, Lambregts-Rommelse NNJ, Altink ME, Buschgens CJM, Nijhuis-van der Sanden MWG, Sergeant JA, Faraone SV, Buitelaar JK. Undertreatment of Motor Problems in Children with ADHD. Child Adolesc Ment Health 2009; 15:85-90. [PMID: 20376200 PMCID: PMC2850122 DOI: 10.1111/j.1475-3588.2009.00538.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND: Motor problems occur in 30% to 50% of children with ADHD, and have a severe impact on daily life. In clinical practice there seems to be little attention for this comorbidity with the possible consequence that these motor problems go undertreated. METHOD: Clinical interview and questionnaire survey of treatment by physiotherapy and factors predicting treatment of motor problems in 235 children with ADHD and 108 controls. RESULTS: Half of motor-affected children had received physiotherapy. Treated children had more severe motor problems, and less frequently presented with comorbid anxiety and conduct disorder. Treated and untreated children were similar in age, and rated similarly on ADHD inattentive and hyperactive-impulsive scales and parental socio-economic status. CONCLUSION: Currently, undertreatment of motor problems in ADHD occurs. Behavioural factors play a role in referral and intervention.
Collapse
Affiliation(s)
- Ellen A Fliers
- Department of Psychiatry, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Altink ME, Slaats-Willemse DIE, Rommelse NNJ, Buschgens CJM, Fliers EA, Arias-Vásquez A, Xu X, Franke B, Sergeant JA, Faraone SV, Buitelaar JK. Effects of maternal and paternal smoking on attentional control in children with and without ADHD. Eur Child Adolesc Psychiatry 2009; 18:465-75. [PMID: 19288168 PMCID: PMC2718195 DOI: 10.1007/s00787-009-0001-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Accepted: 01/19/2009] [Indexed: 02/06/2023]
Abstract
Maternal smoking during pregnancy is a risk factor for attention-deficit/hyperactivity disorder (ADHD), but data on its adverse effects on cognitive functioning are sparse and inconsistent. Since the effect of maternal smoking during pregnancy may be due to correlated genetic risk factors rather than being a pure environmental effect, we examined the effect of prenatal exposure to smoking on attentional control, taking into account the effects of both maternal and paternal smoking, and examined whether these effects were genetically mediated by parental genotypes. We further examined whether the effect of prenatal exposure to smoking on attentional control interacted with genotypes of the child. Participants were 79 children with ADHD, ascertained for the International Multi-centre ADHD Gene project (IMAGE), and 105 normal controls. Attentional control was assessed by a visual continuous performance task. Three genetic risk factors for ADHD (DRD4 7-repeat allele of the exon 3 variable number of tandem repeats (VNTR), DAT1 10/10 genotype of the VNTR located in the 3' untranslated region, and the DAT1 6/6 genotype of the intron 8 VNTR) were included in the analyses. Paternal smoking had a negative effect on attentional control in children with ADHD and this effect appeared to be mediated by genetic risk factors. The prenatal smoking effect did not interact with genotypes of the child. Maternal smoking had no main effect on attentional control, which may be due to lower smoking rates. This study suggests that the effects of paternal smoking on attentional control in children with ADHD should be considered a proxy for ADHD and/or smoking risk genes. Future studies should examine if the results can be generalized to other cognitive domains.
Collapse
Affiliation(s)
- Marieke E. Altink
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands ,Karakter Child and Adolescent University Centre Nijmegen, Reinier Postlaan 12, 6525 GC Nijmegen, The Netherlands
| | - Dorine I. E. Slaats-Willemse
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands ,Karakter Child and Adolescent University Centre Nijmegen, Reinier Postlaan 12, 6525 GC Nijmegen, The Netherlands
| | - Nanda N. J. Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Van der Boechorststraat 1, 1081 BT Amsterdam, The Netherlands
| | - Cathelijne J. M. Buschgens
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands
| | - Ellen A. Fliers
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands
| | - Alejandro Arias-Vásquez
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands ,Department of Human Genetics, Radboud University Nijmegen Medical Centre, HP 855, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Xiaohui Xu
- MRC Social Genetic Developmental and Psychiatry Centre, Institute of Psychiatry, King’s College London, De Crespigny Park, London, SE5 8AF UK
| | - Barbara Franke
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands ,Department of Human Genetics, Radboud University Nijmegen Medical Centre, HP 855, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Joseph A. Sergeant
- Department of Clinical Neuropsychology, VU University Amsterdam, Van der Boechorststraat 1, 1081 BT Amsterdam, The Netherlands
| | - Stephen V. Faraone
- Departments of Psychiatry and Neuroscience & Physiology, SUNY Upstate Medical University, Weiskotten Hall 3285, Syracuse, NY 13210 USA
| | - Jan K. Buitelaar
- Department of Psychiatry, Donders Centre for Neuroscience, Radboud University Nijmegen Medical Centre, P.O. Box 9101, HP 966, 6500 HB Nijmegen, The Netherlands ,Karakter Child and Adolescent University Centre Nijmegen, Reinier Postlaan 12, 6525 GC Nijmegen, The Netherlands
| |
Collapse
|
6
|
Rommelse NNJ, Altink ME, Fliers EA, Martin NC, Buschgens CJM, Hartman CA, Buitelaar JK, Faraone SV, Sergeant JA, Oosterlaan J. Comorbid problems in ADHD: degree of association, shared endophenotypes, and formation of distinct subtypes. Implications for a future DSM. J Abnorm Child Psychol 2009; 37:793-804. [PMID: 19308723 PMCID: PMC2708322 DOI: 10.1007/s10802-009-9312-6] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We aimed to assess which comorbid problems (oppositional defiant behaviors, anxiety, autistic traits, motor coordination problems, and reading problems) were most associated with Attention-Deficit/Hyperactivity Disorder (ADHD); to determine whether these comorbid problems shared executive and motor problems on an endophenotype level with ADHD; and to determine whether executive functioning (EF)-and motor-endophenotypes supported the hypothesis that ADHD with comorbid problems is a qualitatively different phenotype than ADHD without comorbid problems. An EF-and a motor-endophenotype were formed based on nine neuropsychological tasks administered to 816 children from ADHD-and control-families. Additional data on comorbid problems were gathered using questionnaires. Results indicated that oppositional defiant behaviors appeared the most important comorbid problems of ADHD, followed by autistic traits, and than followed by motor coordination problems, anxiety, and reading problems. Both the EF-and motor-endophenotype were correlated and cross-correlated in siblings to autistic traits, motor coordination problems and reading problems, suggesting ADHD and these comorbid problems may possibly share familial/genetic EF and motor deficits. No such results were found for oppositional defiant behaviors and anxiety. ADHD in co-occurrence with comorbid problems may not be best seen as a distinct subtype of ADHD, but further research is warranted.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Nijmeijer JS, Hoekstra PJ, Minderaa RB, Buitelaar JK, Altink ME, Buschgens CJM, Fliers EA, Rommelse NNJ, Sergeant JA, Hartman CA. PDD symptoms in ADHD, an independent familial trait? J Abnorm Child Psychol 2009; 37:443-53. [PMID: 19051006 DOI: 10.1007/s10802-008-9282-0] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The aims of this study were to investigate whether subtle PDD symptoms in the context of ADHD are transmitted in families independent of ADHD, and whether PDD symptom familiality is influenced by gender and age. The sample consisted of 256 sibling pairs with at least one child with ADHD and 147 healthy controls, aged 5-19 years. Children who fulfilled criteria for autistic disorder were excluded. The Children's Social Behavior Questionnaire (CSBQ) was used to assess PDD symptoms. Probands, siblings, and controls were compared using analyses of variance. Sibling correlations were calculated for CSBQ scores after controlling for IQ, ADHD, and comorbid anxiety. In addition, we calculated cross-sibling cross-trait correlations. Both children with ADHD and their siblings had higher PDD levels than healthy controls. The sibling correlation was 0.28 for the CSBQ total scale, with the CSBQ stereotyped behavior subscale showing the strongest sibling correlation (r = 0.35). Sibling correlations remained similar in strength after controlling for IQ and ADHD, and were not confounded by comorbid anxiety. Sibling correlations were higher in female than in male probands. The social subscale showed stronger sibling correlations in elder than in younger sibling pairs. Cross-sibling cross-trait correlations for PDD and ADHD were weak and not-significant. The results confirm that children with ADHD have high levels of PDD symptoms, and further suggest that the familiality of subtle PDD symptoms in the context of ADHD is largely independent from ADHD familiality.
Collapse
Affiliation(s)
- J S Nijmeijer
- Department of Psychiatry, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Buschgens CJM, Swinkels SHN, van Aken MAG, Ormel J, Verhulst FC, Buitelaar JK. Externalizing behaviors in preadolescents: familial risk to externalizing behaviors, prenatal and perinatal risks, and their interactions. Eur Child Adolesc Psychiatry 2009; 18:65-74. [PMID: 18587681 DOI: 10.1007/s00787-008-0704-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/27/2008] [Indexed: 11/24/2022]
Abstract
BACKGROUND Accumulating evidence indicates that there is a rich and varied interplay between persons and their environments, which strongly suggests that this involves gene-environment correlations and interactions. We investigated whether familial risk (FR) to externalizing behaviors and prenatal and perinatal risk factors, separately or in interaction with each other, predicted externalizing behaviors. METHODS The subjects were 10- to 12-year-old preadolescents who were taking part in TRAILS, a large prospective population-based cohort study (N = 2,230). Regression analyses were used to determine the relative contribution of FR and prenatal and perinatal risks to parent and teacher ratings of inattention, hyperactivity/impulsivity aggression, and delinquency. RESULTS Regression models explained between 6 and 11% of the variance of externalizing behaviors. We found main effects of FR (vs. no FR), macrosomia (birth weight > 4,500 g), maternal prenatal smoking (MPS), pregnancy and delivery complications (PDCs), and gender that were rather consistent across rater and outcome measures. For some outcome measures, the effect of MPS and PDCs depended on the presence of FR. These included both positive and negative interaction effects. Correlations between FR and prenatal and perinatal risks were significant but rather low. CONCLUSIONS Both main effects and interaction effects of FR and prenatal and perinatal risks contributed to externalizing behaviors in preadolescents, but all effects were of small size. Further research including use of candidate gene polymorphisms is necessary to identify the underlying neurobiological mechanisms of these main and interaction effects.
Collapse
Affiliation(s)
- Cathelijne J M Buschgens
- Department of Psychiatry, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
| | | | | | | | | | | |
Collapse
|
9
|
Rommelse NNJ, Altink ME, Arias-Vásquez A, Buschgens CJM, Fliers E, Faraone SV, Buitelaar JK, Sergeant JA, Franke B, Oosterlaan J. A review and analysis of the relationship between neuropsychological measures and DAT1 in ADHD. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:1536-46. [PMID: 18729135 DOI: 10.1002/ajmg.b.30848] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Meta-analyses indicate that the gene coding for the dopamine transporter (DAT1 or SLC6A3) is associated with an increased risk for ADHD. The mechanisms of this gene for ADHD are unclear. We systematically reviewed studies linking the VNTR in the 3' UTR of the DAT1 to neurophysiological and neuropsychological measures. In addition, a broad set of executive/cognitive and motor tests was administered to 350 children (5-11 years) and adolescents (11-19 years) with ADHD and 195 non-affected siblings. Two VNTRs (in intron 8 and the 3' UTR) and four SNPs (two 5' and two 3') in DAT1 were genotyped. The effect of the polymorphisms on neuropsychological functioning was studied. The review indicated that the majority of studies did not find a relation between DAT1 and neurophysiological or neuropsychological measures. In our sample, several of the polymorphisms of DAT1 were associated with ADHD and ADHD was associated with impaired neuropsychological functioning. However, none of the DAT1 polymorphisms was convincingly associated with neuropsychological dysfunctioning. This suggests that the effect of DAT1 on ADHD was not mediated by neuropsychological performance. However, since DAT1 is mainly expressed in the striatum and not the prefrontal cortex, it may influence striatum-related functions (such as delay aversion) more heavily than prefrontal related functions (such as executive functions). Associations of DAT1 with ADHD were only found in adolescents, which may suggest that DAT1 mainly exerts its effect in adolescence, and/or that having a more persistent form of ADHD may mark a more severe or homogeneous genetic form of the disorder.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Rommelse NNJ, Altink ME, Arias-Vásquez A, Buschgens CJM, Fliers E, Faraone SV, Buitelaar JK, Sergeant JA, Oosterlaan J, Franke B. Differential association between MAOA, ADHD and neuropsychological functioning in boys and girls. Am J Med Genet B Neuropsychiatr Genet 2008; 147B:1524-30. [PMID: 18726986 DOI: 10.1002/ajmg.b.30845] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is more common in boys than in girls. It has been hypothesized that this sex difference might be related to genes on the X-chromosome, like Monoamine Oxidase A (MAOA). Almost all studies on the role of MAOA in ADHD have focused predominantly on boys, making it unknown whether MAOA also has an effect on ADHD in girls, and few studies have investigated the relationship between MAOA and neuropsychological functioning, yet this may provide insight into the pathways leading from genotype to phenotype. The current study set out to examine the relationship between MAOA, ADHD, and neuropsychological functioning in both boys (265 boys with ADHD and 89 male non-affected siblings) and girls (85 girls with ADHD and 106 female non-affected siblings). A haplotype was used based on three single nucleotide polymorphisms (SNPs) (rs12843268, rs3027400, and rs1137070). Two haplotypes (GGC and ATT) captured 97% of the genetic variance in the investigated MAOA SNPs. The ATT haplotype was more common in non-affected siblings (P = 0.025), conferring a protective effect for ADHD in both boys and girls. The target and direction of the MAOA effect on neuropsychological functioning was different in boys and girls: The ATT haplotype was associated with poorer motor control in boys (P = 0.002), but with better visuo-spatial working memory in girls (P = 0.01). These findings suggest that the genetic and neuropsychological mechanisms underlying ADHD may be different in boys and girls and underline the importance of taking into account sex effects when studying ADHD.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Rommelse NNJ, Altink ME, Oosterlaan J, Buschgens CJM, Buitelaar J, Sergeant JA. Support for an independent familial segregation of executive and intelligence endophenotypes in ADHD families. Psychol Med 2008; 38:1595-1606. [PMID: 18261248 DOI: 10.1017/s0033291708002869] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Impairments in executive functioning (EF) and intelligence quotient (IQ) are frequently observed in children with attention deficit hyperactivity disorder (ADHD). The aim of this paper was twofold: first, to examine whether both domains are viable endophenotypic candidates for ADHD and second to investigate whether deficits in both domains tend to co-segregate within families. METHOD A large family-based design was used, including 238 ADHD families (545 children) and 147 control families (271 children). Inhibition, visuospatial and verbal working memory, and performance and verbal IQ were analysed. RESULTS Children with ADHD, and their affected and non-affected siblings were all impaired on the EF measures and verbal IQ (though unimpaired on performance IQ) and all measures correlated between siblings. Correlations and sibling cross-correlations were not significant between EF and IQ, though they were significant between the measures of one domain. Group differences on EF were not explained by group differences on IQ and vice versa. The discrepancy score between EF and IQ correlated between siblings, indicating that siblings resembled each other in their EF-IQ discrepancy instead of having generalized impairments across both domains. Siblings of probands who had an EF but not IQ impairment, showed a comparable disproportionate lower EF score in relation to IQ score. The opposite pattern was not significant. CONCLUSIONS The results supported the viability of EF and IQ as endophenotypic candidates for ADHD. Most findings support an independent familial segregation of both domains. Within EF, similar familial factors influenced inhibition and working memory. Within IQ, similar familial factors influenced verbal and performance IQ.
Collapse
Affiliation(s)
- N N J Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Van der Boechorststraat 1, Amsterdam, The Netherlands.
| | | | | | | | | | | |
Collapse
|
12
|
Rommelse NNJ, Altink ME, Oosterlaan J, Beem L, Buschgens CJM, Buitelaar J, Sergeant JA. Speed, variability, and timing of motor output in ADHD: which measures are useful for endophenotypic research? Behav Genet 2008; 38:121-32. [PMID: 18071893 PMCID: PMC2257997 DOI: 10.1007/s10519-007-9186-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Accepted: 11/27/2007] [Indexed: 11/17/2022]
Abstract
Attention-Deficit/Hyperactivity Disorder (ADHD) shares a genetic basis with motor coordination problems and probably motor timing problems. In line with this, comparable problems in motor timing should be observed in first degree relatives and might, therefore, form a suitable endophenotypic candidate. This hypothesis was investigated in 238 ADHD-families (545 children) and 147 control-families (271 children). A motor timing task was administered, in which children had to produce a 1,000 ms interval. In addition to this task, two basic motor tasks were administered to examine speed and variability of motor output, when no timing component was required. Results indicated that variability in motor timing is a useful endophenotypic candidate: It was clearly associated with ADHD, it was also present in non-affected siblings, and it correlated within families. Accuracy (under- versus over-production) in motor timing appeared less useful: Even though accuracy was associated with ADHD (probands and affected siblings had a tendency to under-produce the 1,000 ms interval compared to controls), non-affected siblings did not differ from controls and sibling correlations were only marginally significant. Slow and variable motor output without timing component also appears present in ADHD, but not in non-affected siblings, suggesting these deficits not to be related to a familial vulnerability for ADHD. Deficits in motor timing could not be explained by deficits already present in basic motor output without a timing component. This suggests abnormalities in motor timing were predominantly related to deficient motor timing processes and not to general deficient motor functioning. The finding that deficits in motor timing run in ADHD-families suggests this to be a fruitful domain for further exploration in relation to the genetic underpinnings of ADHD.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, VU University Amsterdam, Van der Boechorststraat 1, Amsterdam 1081 BT, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
13
|
Fliers E, Rommelse N, Vermeulen SHHM, Altink M, Buschgens CJM, Faraone SV, Sergeant JA, Franke B, Buitelaar JK. Motor coordination problems in children and adolescents with ADHD rated by parents and teachers: effects of age and gender. J Neural Transm (Vienna) 2007; 115:211-20. [PMID: 17994185 DOI: 10.1007/s00702-007-0827-0] [Citation(s) in RCA: 138] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2007] [Accepted: 09/19/2007] [Indexed: 12/21/2022]
Abstract
OBJECTIVE ADHD is frequently accompanied by motor coordination problems. However, the co-occurrence of poor motor performance has received less attention in research than other coexisting problems in ADHD. The underlying mechanisms of this association remain unclear. Therefore, we investigated the prevalence of motor coordination problems in a large sample of children with ADHD, and the relationship between motor coordination problems and inattentive and hyperactive/impulsive symptoms. Furthermore, we assessed whether the association between ADHD and motor coordination problems was comparable across ages and was similar for both genders. METHOD We investigated 486 children with ADHD and 269 normal controls. Motor coordination problems were rated by parents (Developmental Coordination Disorder Questionnaire) and teachers (Groningen Motor Observation Scale). RESULTS Parents and teachers reported motor coordination problems in about one third of children with ADHD. Problems of fine and gross motor skills, coordination skills and motor control were all related to inattentive rather than hyperactive/impulsive symptoms. Relative to controls, motor coordination problems in ADHD were still present in teenagers according to parents; the prevalence diminished somewhat according to teachers. Boys and girls with ADHD were comparably affected, but motor performance in controls was better in girls than in boys. CONCLUSIONS Motor coordination problems were reported in one third of children with ADHD and affected both boys and girls. These problems were also apparent in adolescents with ADHD. Clinicians treating children with ADHD should pay attention to co-occurring motor coordination problems because of the high prevalence and the negative impact of motor coordination problems on daily life.
Collapse
Affiliation(s)
- E Fliers
- Department of Psychiatry, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Rommelse NNJ, Altink ME, Oosterlaan J, Buschgens CJM, Buitelaar J, De Sonneville LMJ, Sergeant JA. Motor control in children with ADHD and non-affected siblings: deficits most pronounced using the left hand. J Child Psychol Psychiatry 2007; 48:1071-9. [PMID: 17995482 DOI: 10.1111/j.1469-7610.2007.01781.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) is strongly influenced by heritability. Identifying heritable vulnerability traits (endophenotypes) that mark a relatively high risk of developing the disorder can contribute to the identification of risk genes. A fruitful area for the search for such endophenotypes may be motor control in children with ADHD, since the disorder is frequently accompanied by motor problems. METHOD The current study used a large sample of 350 children with ADHD, 195 non-affected siblings and 271 normal controls aged 5-19 years. Children were administered two computerised motor control tasks in which they had to trace a path between two circles (Tracking task) and follow a randomly moving target (Pursuit task). Both tasks were performed with both the right and the left hand. RESULTS Children with ADHD were less precise and stable than controls. Non-affected siblings also deviated from controls, but only on the Tracking task. Group differences were modulated by the use of the right versus the left hand: no group differences emerged when the right hand was used, yet group differences did emerge when the left hand was used. Performance on both tasks was significantly familial. CONCLUSIONS Imprecision and instability of movements in children with ADHD and in their non-affected siblings as measured by the Tracking task might be suitable endophenotypic candidates: these deficits are familially present in children having ADHD as well as in their non-affected siblings. Motor performance might be best assessed in children using their left hand, because motor control deficits are most pronounced using the left hand. This might relate to right hemispheric brain pathology in children with ADHD (and possibly in their non-affected siblings) that is related to the control of the left hand and/or relate to differential effects of daily life practice on both hands, which may be smaller on the left hand.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
15
|
Rommelse NNJ, Altink ME, de Sonneville LMJ, Buschgens CJM, Buitelaar J, Oosterlaan J, Sergeant JA. Are Motor Inhibition and Cognitive Flexibility Dead Ends in ADHD? J Abnorm Child Psychol 2007; 35:957-67. [PMID: 17503173 DOI: 10.1007/s10802-007-9146-z] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Accepted: 04/26/2007] [Indexed: 10/23/2022]
Abstract
Executive dysfunction has been postulated as the core deficit in ADHD, although many deficits in lower order cognitive processes have also been identified. By obtaining an appropriate baseline of lower order cognitive functioning light may be shed on as to whether executive deficits result from problems in lower order and/or higher order cognitive processes. We examined motor inhibition and cognitive flexibility in relation to a baseline measure in 816 children from ADHD and control families. Multiple children in a family were tested in order to examine the familiality of the measures. No evidence was found for deficits in motor inhibition or cognitive flexibility in children with ADHD or their nonaffected siblings: Compared to their baseline speed and accuracy of responding, children with ADHD and their (non)affected siblings were not disproportionally slower or inaccurate when demands for motor inhibition or cognitive flexibility were added to the task. However, children with ADHD and their (non)affected siblings were overall less accurate than controls, which could not be attributed to differences in response speed. This suggests that inaccuracy of responding is characteristic of children having (a familial risk for) ADHD. Motor inhibition and cognitive flexibility as operationalized with mean reaction time were found to be familial. It is concluded that poorer performance on executive tasks in children with ADHD and their (non)affected siblings may result from deficiencies in lower order cognitive processes and not (only) from higher order cognitive processes/executive functions.
Collapse
Affiliation(s)
- Nanda N J Rommelse
- Department of Clinical Neuropsychology, Vrije Universiteit Amsterdam, Van der Boechorststraat 1, 1081 BT, Amsterdam, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|