Aim
We examined key features of two outcome measures for social dysfunction and autism spectrum disorder traits, the Social Responsiveness Scale, Second Edition (SRS‐2) and the Social Skills ...Improvement System – Rating Scales (SSIS‐RS), in children with neurofibromatosis type 1 (NF1). The aim of the study was to provide objective evidence as to which behavioural endpoint should be used in clinical trials.
Method
Cross‐sectional behavioural and demographic data were pooled from four paediatric NF1 tertiary referral centres in Australia and the United States (N=122; 65 males, 57 females; mean age SD 9y 2mo 3y, range 3–15y).
Results
Distributions of SRS‐2 and SSIS‐RS scores were unimodal and both yielded deficits, with a higher proportion of severely impaired scores on the SRS‐2 (16.4%) compared to the SSIS‐RS (8.2%). Pearson’s product‐moment correlations revealed that both questionnaires were highly related to each other (r=−0.72, p<0.001) and to measures of adaptive social functioning (both p<0.001). Both questionnaires were significantly related to attention‐deficit/hyperactivity disorder symptoms, but only very weakly associated with intelligence.
Interpretation
The SRS‐2 and SSIS‐RS capture social dysfunction associated with NF1, suggesting both may be suitable choices for assessing social outcomes in this population in a clinical trial. However, careful thought needs to be given to the nature of the intervention when selecting either as a primary endpoint.
What this paper adds
The Social Responsiveness Scale, Second Edition yielded a large deficit relative to population norms.
The Social Skills Improvement System – Rating Scales yielded a moderate deficit relative to population norms.
Both scales were highly correlated, suggesting that they are measuring a unitary construct.
What this paper adds
The Social Responsiveness Scale, Second Edition yielded a large deficit relative to population norms.
The Social Skills Improvement System – Rating Scales yielded a moderate deficit relative to population norms.
Both scales were highly correlated, suggesting that they are measuring a unitary construct.
This article is commented on by Huijbregts on page 773 of this issue.
The aim of this study was to examine functional attention and executive deficits present in everyday living in a large sample of children with neurofibromatosis type 1 (NF1). Data are presented from ...199 children with NF1 and 55 unaffected sibling controls who were administered the Behavior Rating Inventory of Executive Function (BRIEF) and Conners' ADHD DSM-IV Scales (CADS). Convergent validity was examined by correlating scale scores from these functional measures with scores from traditional cognitive measures of attention and executive function. Results indicated global functional attention and executive deficits in children with NF1. Relationships between functional impairments and scores on cognitive measures were inconsistent; at best, the magnitude of these relationships was in the moderate range, yet there was also a lack of association between many cognitive tasks and the functional skills they purport to assess. Findings suggest that cognitive and functional measures may tap different constructs and that neuropsychological evaluations should be supplemented with functional assessment tools to provide a more accurate and sensitive encapsulation of a child's strengths and weaknesses to guide remediation programs.
We compared cognitive functioning, academic ability, and the predictors of academic underachievement in children with neurofibromatosis type 1 (NF1) (n = 132), children with NF1 and comorbid ...attention deficit hyperactivity disorder (NF1 + ADHD) (n = 60), and unaffected controls (n = 52). Results indicate the presence of ADHD burdens some aspects of cognitive functioning and learning in NF1. Inattention and executive dysfunction are general characteristics of the NF1 cognitive phenotype and significantly undermine academic achievement across children with NF1.
IntroductionTranslating scientific advances in genomic medicine into evidence-based clinical practice is challenging. Studying the natural translation of genomics into ‘early-adopting’ health system ...sectors is essential. We will (a) examine 29 health systems (Australian and Melbourne Genomics Health Alliance flagships) integrating genomics into practice and (b) combine this learning to co-design and test an evidence-based generalisable toolkit for translating genomics into healthcare.Methods and analysisTwenty-nine flagships integrating genomics into clinical settings are studied as complex adaptive systems to understand emergent and self-organising behaviours among inter-related actors and processes. The Effectiveness–Implementation Hybrid approach is applied to gather information on the delivery and potential for real-world implementation. Stages ‘1’ and ‘2a’ (representing hybrid model 1) are the focus of this protocol. The Translation Science to Population Impact (TSci Impact) framework is used to study policy decisions and service provision, and the Theoretical Domains Framework (TDF) is used to understand individual level behavioural change; both frameworks are applied across stages 1 and 2a. Stage 1 synthesises interview data from 32 participants involved in developing the genomics clinical practice systems and approaches across five ‘demonstration-phase’ (early adopter) flagships. In stage 2a, stakeholders are providing quantitative and qualitative data on process mapping, clinical audits, uptake and sustainability (TSci Impact), and psychosocial and environmental determinants of change (TDF). Findings will be synthesised before codesigning an intervention toolkit to facilitate implementation of genomic testing. Study methods to simultaneously test the comparative effectiveness of genomic testing and the implementation toolkit (stage 2b), and the refined implementation toolkit while simply observing the genomics intervention (stage 3) are summarised.Ethics and disseminationEthical approval has been granted. The results will be disseminated in academic forums and used to refine interventions to translate genomics evidence into healthcare. Non-traditional academic dissemination methods (eg, change in guidelines or government policy) will also be employed.
Existing research has demonstrated elevated autistic behaviours in children with neurofibromatosis type 1 (NF1), but the autistic phenotype and its relationship to other neurodevelopmental ...manifestations of NF1 remains unclear. To address this gap, we performed detailed characterisation of autistic behaviours in children with NF1 and investigated their association with other common NF1 child characteristics.
Participants were drawn from a larger cross-sectional study examining autism in children with NF1. The population analysed in this study scored above threshold on the Social Responsiveness Scale-Second Edition (T-score ≥ 60; 51% larger cohort) and completed the Autism Diagnostic Interview-Revised (ADI-R) and/or the Autism Diagnostic Observation Schedule-Second Edition (ADOS-2). All participants underwent evaluation of their intellectual function, and behavioural data were collected via parent questionnaires.
The study cohort comprised 68 children (3-15 years). Sixty-three per cent met the ADOS-2 'autism spectrum' cut-off, and 34% exceeded the more stringent threshold for 'autistic disorder' on the ADI-R. Social communication symptoms were common and wide-ranging, while restricted and repetitive behaviours (RRBs) were most commonly characterised by 'insistence on sameness' (IS) behaviours such as circumscribed interests and difficulties with minor changes. Autistic behaviours were weakly correlated with hyperactive/impulsive attention deficit hyperactivity disorder (ADHD) symptoms but not with inattentive ADHD or other behavioural characteristics. Language and verbal IQ were weakly related to social communication behaviours but not to RRBs.
Lack of genetic validation of NF1, no clinical diagnosis of autism, and a retrospective assessment of autistic behaviours in early childhood.
Findings provide strong support for elevated autistic behaviours in children with NF1. While these behaviours were relatively independent of other NF1 comorbidities, the importance of taking broader child characteristics into consideration when interpreting data from autism-specific measures in this population is highlighted. Social communication deficits appear similar to those observed in idiopathic autism and are coupled with a unique RRB profile comprising prominent IS behaviours. This autistic phenotype and its relationship to common NF1 comorbidities such as anxiety and executive dysfunction will be important to examine in future research. Current findings have important implications for the early identification of autism in NF1 and clinical management.
Objective: We examined the contribution of attention and executive cognitive processes to ADHD symptomatology in NF1, as well as the relationships between cognition and ADHD symptoms with functional ...outcomes. Methods: The study sample consisted of 141 children and adolescents with NF1. Children were administered neuropsychological tests that assessed attention and executive function, from which latent cognitive variables were derived. ADHD symptomatology, adaptive skills, and quality of life (QoL) were assessed using parent-rated questionnaires. Path analyses were conducted to test relationships among cognitive functioning, ADHD symptomatology, and functional outcomes. Results: Significant deficits were observed on all outcome variables. Cognitive variables did not predict ADHD symptomatology. Neither did they predict functional outcomes. However, elevated ADHD symptomatology significantly predicted functional outcomes. Conclusion: Irrespective of cognitive deficits, elevated ADHD symptoms in children with NF1 negatively impact daily functioning and emphasize the importance of interventions aimed at minimizing ADHD symptoms in NF1.
Objective To establish the developmental trajectory of young children with neurofibromatosis type 1 (NF1) during the first 4 years of life. Study design In this longitudinal study, 39 children with ...NF1 and 39 controls were assessed with the Bayley Scales of Infant Development, Second Edition at 21 (time point 1, or T1) and 30 months (T2) of age, and the Wechsler Preschool and Primary Scale of Intelligence, Third Edition at 40 months (T3). Language was also assessed at T2 and T3. Parents rated their child's productive vocabulary at T1 and T2, and behavior at each time point. Linear mixed models were performed to examine cognitive development and behavior over time. Linear regressions were conducted to determine whether mental development and productive vocabulary at T1 or T2 predicted intellectual and language outcomes at T3. Results Over time, the NF1 group had significantly lower cognitive scores than controls. Parent ratings indicated no group differences in behavior at each time point. Earlier mental function significantly predicted later general intelligence. Earlier productive vocabulary was a significant predictor of later language skills. Conclusions There are consistent differences over time in cognitive performance between children with NF1 and unaffected peers during the early childhood period. Earlier mental function and productive vocabulary are significant predictors of subsequent general intelligence and performance on language measures in NF1. This provides an opportunity for early identification and treatment for young children with NF1 who may show signs of impairments in these developmental domains.
Despite the evidence of elevated autistic behaviors and co-occurring neurodevelopmental difficulties in many children with neurofibromatosis type 1 (NF1), we have a limited understanding of the ...sensory processing challenges that may occur with the condition. This study examined the sensory profile of children and adolescents with NF1 and investigated the relationships between the sensory profiles and patient characteristics and neuropsychological functioning. The parent/caregivers of 152 children with NF1 and 96 typically developing children completed the Sensory Profile 2 (SP2), along with standardized questionnaires assessing autistic behaviors, ADHD symptoms, internalizing symptoms, adaptive functioning, and social skills. Intellectual functioning was also assessed. The SP2 data indicated elevated sensory processing problems in children with NF1 compared to typically developing children. Over 40% of children with NF1 displayed differences in sensory registration (missing sensory input) and were unusually sensitive to and unusually avoidant of sensory stimuli. Sixty percent of children with NF1 displayed difficulties in one or more sensory modalities. Elevated autistic behaviors and ADHD symptoms were associated with more severe sensory processing difficulties. This first detailed assessment of sensory processing, alongside other clinical features, in a relatively large cohort of children and adolescents with NF1 demonstrates the relationships between sensory processing differences and adaptive skills and behavior, as well as psychological well-being. Our characterization of the sensory profile within a genetic syndrome may help facilitate more targeted interventions to support overall functioning.
To describe the clinical and genetic characteristics of presynaptic congenital myasthenic syndrome secondary to biallelic variants in SLC18A3.
Individuals from 2 families were identified with ...biallelic variants in SLC18A3, the gene encoding the vesicular acetylcholine transporter (VAChT), through whole-exome sequencing.
The patients demonstrated features seen in presynaptic congenital myasthenic syndrome, including ptosis, ophthalmoplegia, fatigable weakness, apneic crises, and deterioration of symptoms in cold water for patient 1. Both patients demonstrated moderate clinical improvement on pyridostigmine. Patient 1 had a broader phenotype, including learning difficulties and left ventricular dysfunction. Electrophysiologic studies were typical for a presynaptic defect. Both patients showed profound electrodecrement on low-frequency repetitive stimulation followed by a prolonged period of postactivation exhaustion. In patient 1, this was unmasked only after isometric contraction, a recognized feature of presynaptic disease, emphasizing the importance of activation procedures.
VAChT is responsible for uptake of acetylcholine into presynaptic vesicles. The clinical and electrographic characteristics of the patients described are consistent with previously reported mouse models of VAChT deficiency. These findings make it very likely that defects in VAChT due to variants in SLC18A3 are a cause of congenital myasthenic syndrome in humans.
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