Longitudinal follow-up of metformin treatment in Fragile X Syndrome.

Introduction: Metformin has been used as a targeted treatment to potentially improve cognition and slow the typical IQ decline that occurs during development among individuals with fragile X syndrome (FXS). In this follow-up study, we are following the trajectory of IQ and adaptive behavior changes over 1 to 3 years in individuals with FXS who are clinically treated with metformin in an open label trial. Method: Individuals with FXS ages 6 to 25 years (mean 13.15 ± 5.50) and nonverbal IQ mean 57.69 (±15.46) were treated for 1-3 years (1.88 ± 0.63). They all had a baseline IQ test using the Leiter-III non-verbal cognitive assessment and the Vineland-III adaptive behavior assessment before the start of metformin. Repeat Leiter-III and Vineland-III were completed after at least 1 year of metformin (500-1,000 mg/dose given twice a day). Result: There were no significant changes in non-verbal IQ or in the adaptive behavior measurements at FDR < 0.05. The findings thus far indicate that both IQ and adaptive behavior are stable over time, and we did not see a significant decline in either measure. Conclusion: Overall, the small sample size and short follow-up duration limit the interpretation of the effects of metformin on cognitive development and adaptive functioning. There is individual variability but overall for the group there was no significant decline in IQ or adaptive behavior.

The impact of social-environmental factors on IQ in syndromic intellectual developmental disabilities.

Despite having the same underlying genetic etiology, individuals with the same syndromic form of intellectual developmental disability (IDD) show a large degree of interindividual differences in cognition and IQ. Research indicates that up to 80% of the variation in IQ scores among individuals with syndromic IDDs is attributable to nongenetic effects, including social-environmental factors. In this narrative review, we summarize evidence of the influence that factors related to economic stability (focused on due to its prevalence in existing literature) have on IQ in individuals with syndromic IDDs. We also highlight the pathways through which economic stability is hypothesized to impact cognitive development and drive individual differences in IQ among individuals with syndromic IDDs. We also identify broader social-environmental factors (e.g., social determinants of health) that warrant consideration in future research, but that have not yet been explored in syndromic IDDs. We conclude by making recommendations to address the urgent need for further research into other salient factors associated with heterogeneity in IQ. These recommendations ultimately may shape individual- and community-level interventions and may inform systems-level public policy efforts to promote the cognitive development of and improve the lived experiences of individuals with syndromic IDDs.

Parental Responsivity and Child Communication During Mother-Child and Father-Child Interactions in Fragile X Syndrome.

PURPOSE: Past research shows that parentally responsive behavior toward the child positively influences language development in both neurotypical children and children with intellectual and developmental disabilities, including those with fragile X syndrome (FXS); however, most studies have focused exclusively on the mother-child relationship. The current study examined relationships between parent behavior (i.e., responsivity and behavior management) and child language performance in both mother-child and father-child interactions, as well as relationships between child characteristics and both parent behavior and child language. METHOD: Participants were 23 families of young boys with FXS between 3 and 7 years of age. Mothers and fathers independently completed questionnaires assessing child characteristics and separately engaged in 12-min play-based interactions with their child via telehealth. One parent also completed a comprehensive interview assessing child adaptive behavior. Video recordings of the parent-child interactions were transcribed and coded for parent and child behavior, and measures of parent and child language were obtained from the transcripts. RESULTS: Mothers and fathers used similar rates of responsive behaviors during parent-child interactions, and parental responsivity was positively associated with some aspects of child language performance (i.e., talkativeness and lexical diversity). Parental behavior, however, was not associated with syntactic complexity. Older children and children with higher levels of adaptive behavior had parents who used higher rates of responsive behaviors. Fathers used higher rates of behavior management strategies compared to mothers, and this type of parent behavior was not associated with child language. CONCLUSION: Overall, this study provides evidence that interventions focused on increasing parental responsiveness would be beneficial for families of children with FXS and that these interventions should be delivered early given the association between responsivity and child age. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25229939.

Preliminary psychometric properties of an inhibition task in young children with Down syndrome.

Background: Executive function (EF) skills are important treatment targets for people with Down syndrome (DS); however, few EF measures have been evaluated for use with young children in this population. Methods: The present study evaluated preliminary psychometric properties of a measure of the EF component of inhibition. Participants were 73 children with DS between 2.5 and 8.67 years old who completed an adapted ability to delay task using a desirable toy. Results: Across two separate trials, latencies to touch the toys were significantly correlated. Latencies increased overall with chronological and mental age, with caveats for the youngest and oldest participants. Conclusion: Findings suggest that an adapted prohibition task is an appropriate method of measuring inhibition for children with DS between 4 and 7 years old, though many children in this chronological age range are at early stages of acquiring this skill set.

Parental Survey on Spanish­English Bilingualism in Neurotypical Development and Neurodevelopmental Disabilities in the United States.

Objectives: The cognitive and social benefits of bilingualism for children, including those with neurodevelopmental disabilities (NDDs), have been documented. The present study was designed to characterize and compare English and Spanish use in Hispanic families with and without NDDs residing in the U.S. as well as to understand parental perceptions of their child's bilingualism and of community and professional support. Methods: We conducted an online survey of 84 Spanish-speaking parents of 4- to 24-year-olds with (n = 44) and without NDDs (n = 40) who were born in and living in the U.S. Results: We found that bilingualism was a desired goal for 95% of our families. We also found, however, that 17.1% of parents of children with NDDs have raised them as monolinguals English-speakers, as they thought there were reasons for that, while all families from the NT group raised their children in both languages. In addition, nearly 40% of the NDD children only speak English, compared to a 5% in the NT group. Finally, parents of children with NDDs cite a lack of support for bilingualism in the community (47.6% do not feel supported, compared to a 7.9% in the NT group) and recommendation from professionals as major factors for not raising their children as bilingual. Conclusions: The results suggest a need to educate professionals from many disciplines about the benefits of bilingualism for children with NDDs and for implementation of inclusion policies that provide access to dual-language programs.

Adaptive, behavioral, and cognitive outcomes in individuals with fragile X syndrome with varying autism severity.

This study aimed to determine the association between severity of autism spectrum disorder (ASD) and cognitive, behavioral, and molecular measures in individuals with fragile X syndrome (FXS). Study inclusion criteria included individuals with FXS and (1) age 6-40 years, (2) full-scale IQ < 84, and (3) language ≥3-word phrases. ASD symptom severity was determined by Autism Diagnostic Observation Schedule-2 (ADOS-2). Other measures identified non-verbal IQ, adaptive skills, and aberrant behaviors. Molecular measures included blood FMR1 and CYFIP1 mRNA levels, FMRP and MMP9 levels. Analysis of variance (ANOVA) and Spearman's correlations were used to compare ASD severity groups. Data from 54 individuals was included with no/mild (N = 7), moderate (N = 18), and severe (N = 29) ASD. Individuals with high ASD severity had lower adaptive behavior scores (47.48 ± 17.49) than the no/mild group (69.00 ± 20.45, p = 0.0366); they also had more challenging behaviors, lethargy, and stereotypic behaviors. CYFIP1 mRNA expression levels positively correlated with the ADOS-2 comparison score(r2  = 0.33, p = 0.0349), with no significant correlations with other molecular markers. In conclusion, autism symptom severity is associated with more adverse cognitive and adaptive skills and specific behaviors in FXS, whereas CYFIP1 mRNA expression levels may be a potential biomarker for severity of ASD in FXS.

Extended trajectory of spatial memory errors in typical and atypical development: The role of binding and precision.

Spatial reconstruction, a method for evaluating how individuals remember the placement of objects, has traditionally been evaluated through the aggregate estimation of placement errors. However, this approach may obscure the nature of task errors. Specifically, recent data has suggested the importance of examining the precision of responses, as well as absolute performance on item-context bindings. In contrast to traditional analysis approaches based on the distance between the target and the reconstructed item, in this study we further explored three types of errors (swap error, global error, and local distance) that may all contribute to the distance, with particular emphasis on swap errors and local distance due to their associations with item-context bindings and memory precision, respectively. We examined these errors in children aged 3-18 years, making comparisons between children with typical development (TD) and children with Down syndrome (DS), a population with known memory challenges. As expected, older children outperformed younger children in terms of overall memory accuracy. Of importance is that we measured uneven maturational trajectories of memory abilities across the various error types. Specifically, both remembered locations (irrespective of object identity) and swap errors (object-location binding errors) align with the overall memory accuracy. Memory precision, as measured by local distance in simpler set size 2 trials, mirrored overall memory accuracy. However, for more complex set size 3 trials, local distance remained stable before age 8 and showed age-related change thereafter. The group with DS showed reduced precision compared to a TD matched group, and measures of precision, and to a lesser extent binding errors, correlated with standard neuropsychological outcomes. Overall, our study contributed to a fine-grained understanding of developing spatial memory ability in a large sample of typical developing children and a memory impaired population. These findings contribute to a growing body of research examining precision as a key factor in memory performance.

The Work Ahead for Intellectual and Developmental Disabilities Research.

In "Toward Equity in Research on Intellectual and Developmental Disabilities," we sought to make entrenched assumptions and practices of intellectual and developmental disabilities research visible by explicitly describing the status quo in terms of models of disability, participant and researcher identities, research priorities, and biases in measurement and treatment approaches. We then curated individual- and systems-level actions drawn from disability justice and broader social justice lenses to offer a way forward. We focused on three major areas (i.e., intersectionality and person-centered approaches, participatory research, and interprofessional collaboration), depicting influences, methods, and actions in a framework of disability, identity, and culture. In this Author Response, we address five commentaries that critique and extend that synthesis.

Toward Equity in Research on Intellectual and Developmental Disabilities.

Lack of diversity in IDD research is typically conceptualized only in terms of (1) recruitment of samples that do not appropriately represent the sociodemographics of the population, or (2) the limited number of researchers from historically marginalized backgrounds. Critically, the field also suffers from over-reliance on perspectives and social systems of dominant culture-both in how disability is regarded and in relation to other dimensions of identity and culture. These lenses lead to research findings that reinforce, rather than reduce, social inequities. We propose a framework that minimizes reliance on diagnostic categories, shifts from deficit- to person-centered models, acknowledges people's multiple identities, and includes self-advocates and diverse communities as partners in the research enterprise. The systems change necessary to support this framework is described.

Effects of AFQ056 on language learning in fragile X syndrome.

BACKGROUNDFXLEARN, the first-ever large multisite trial of effects of disease-targeted pharmacotherapy on learning, was designed to explore a paradigm for measuring effects of mechanism-targeted treatment in fragile X syndrome (FXS). In FXLEARN, the effects of metabotropic glutamate receptor type 5 (mGluR5) negative allosteric modulator (NAM) AFQ056 on language learning were evaluated in 3- to 6-year-old children with FXS, expected to have more learning plasticity than adults, for whom prior trials of mGluR5 NAMs have failed.METHODSAfter a 4-month single-blind placebo lead-in, participants were randomized 1:1 to AFQ056 or placebo, with 2 months of dose optimization to the maximum tolerated dose, then 6 months of treatment during which a language-learning intervention was implemented for both groups. The primary outcome was a centrally scored videotaped communication measure, the Weighted Communication Scale (WCS). Secondary outcomes were objective performance-based and parent-reported cognitive and language measures.RESULTSFXLEARN enrolled 110 participants, randomized 99, and had 91 who completed the placebo-controlled period. Although both groups made language progress and there were no safety issues, the change in WCS score during the placebo-controlled period was not significantly different between the AFQ056 and placebo-treated groups, nor were there any significant between-group differences in change in any secondary measures.CONCLUSIONDespite the large body of evidence supporting use of mGluR5 NAMs in animal models of FXS, this study suggests that this mechanism of action does not translate into benefit for the human FXS population and that better strategies are needed to determine which mechanisms will translate from preclinical models to humans in genetic neurodevelopmental disorders.TRIAL REGISTRATIONClincalTrials.gov NCT02920892.FUNDING SOURCESNeuroNEXT network NIH grants U01NS096767, U24NS107200, U24NS107209, U01NS077323, U24NS107183, U24NS107168, U24NS107128, U24NS107199, U24NS107198, U24NS107166, U10NS077368, U01NS077366, U24NS107205, U01NS077179, and U01NS077352; NIH grant P50HD103526; and Novartis IIT grant AFQ056X2201T for provision of AFQ056.

Intercorrelation of Molecular Biomarkers and Clinical Phenotype Measures in Fragile X Syndrome.

This study contributes to a greater understanding of the utility of molecular biomarkers to identify clinical phenotypes of fragile X syndrome (FXS). Correlations of baseline clinical trial data (molecular measures-FMR1 mRNA, CYFIP1 mRNA, MMP9 and FMRP protein expression levels, nonverbal IQ, body mass index and weight, language level, NIH Toolbox, adaptive behavior rating, autism, and other mental health correlates) of 59 participants with FXS ages of 6-32 years are reported. FMR1 mRNA expression levels correlated positively with adaptive functioning levels, expressive language, and specific NIH Toolbox measures. The findings of a positive correlation of MMP-9 levels with obesity, CYFIP1 mRNA with mood and autistic symptoms, and FMR1 mRNA expression level with better cognitive, language, and adaptive functions indicate potential biomarkers for specific FXS phenotypes. These may be potential markers for future clinical trials for targeted treatments of FXS.

Psychometric evaluation of a working memory assessment measure in young children with Down syndrome.

BACKGROUND: Working memory involves the temporary storage and manipulation of information and is frequently an area of challenge for individuals with Down syndrome (DS). Despite the potential benefits of intervention, laboratory assessments of working memory that could capture intervention effects have not undergone rigorous evaluation for use with young children with DS. It is critical to evaluate assessments of working memory in young children with DS to ensure the reliable and accurate measurement of performance. AIM: This study evaluated an adapted laboratory measure of working memory for young children with DS 2-8 years old. METHOD: A self-ordered pointing task, the Garage Game, was administered to 78 children with DS (mean = 5.17 years; SD = 1.49). Adaptations were made to the task to minimize potential DS phenotype-related language and motor confounds. RESULTS: Results indicate that the measure is feasible, scalable, and developmentally sensitive, with minimal floor and practice effects for this population within this chronological and developmental age range. CONCLUSION: These findings demonstrate that the Garage Game is promising for use in studies of early working memory and treatment trials that aim to support the development of this critical dimension of executive functioning for children with DS.

Expressive language sampling and outcome measures for treatment trials in fragile X and down syndromes: composite scores and psychometric properties.

The lack of psychometrically sound outcome measures has been a barrier to evaluating the efficacy of treatments proposed for core symptoms of intellectual disability (ID). Research on Expressive Language Sampling (ELS) procedures suggest it is a promising approach to measuring treatment efficacy. ELS entails collecting samples of a participant's talk in interactions with an examiner that are naturalistic but sufficiently structured to ensure consistency and limit examiner effects on the language produced. In this study, we extended previous research on ELS by analyzing an existing dataset to determine whether psychometrically adequate composite scores reflecting multiple dimensions of language can be derived from ELS procedures administered to 6- to 23-year-olds with fragile X syndrome (n = 80) or Down syndrome (n = 78). Data came from ELS conversation and narration procedures administered twice in a 4-week test-retest interval. We found that several composites emerged from variables indexing syntax, vocabulary, planning processes, speech articulation, and talkativeness, although there were some differences in the composites for the two syndromes. Evidence of strong test-retest reliability and construct validity of two of three composites were obtained for each syndrome. Situations in which the composite scores would be useful in evaluating treatment efficacy are outlined.

Examining indicators of psychosocial risk and resilience in parents of autistic children.

Background: Parents of autistic children experience increased levels of caregiver strain and adverse mental health outcomes, even in comparison to parents of children with other neurodevelopmental disabilities. Previous studies have largely attributed these increased levels of mental health concerns to their child behavioral concerns and autism symptomatology, but less attention has been given to other potential child factors, such as child adaptive functioning. Additionally, little is known about potential protective factors, such as parents' emotion regulation (ER) abilities, that may ameliorate the experience of caregiver strain, anxiety, and depression. Objective: The current study examined the impact of child characteristics (restricted and repetitive behaviors, adaptive functioning and behavioral concerns) on parent mental health outcomes (caregiver strain, anxiety, depression and wellbeing). Additionally, we explore parents' ER abilities as a moderator of the impact of child characteristic on parents' mental health outcomes. Results: Results of linear mixed effect models indicated a significant relationship between parents' ER abilities and all four parent outcomes. Additionally, children's adaptive functioning abilities and repetitive behaviors (RRBs) were significant predictors of caregiving strain. Parents' ER abilities were a significant moderator of the effect of children's repetitive behaviors and adaptive functioning challenges on caregiver strain, such that better ER abilities mitigated the impact of child clinical factors on caregiver strain. Finally, a significant difference was detected for mothers' and fathers' mental health, with mothers reporting higher caregiver strain, and more symptoms of anxiety and depression than did fathers. Conclusion: This study leveraged a large sample of autistic children and their biological parents to examine the relationship between children's clinical characteristics and parents' psychological wellbeing. Results indicate that, although parents of autistic children do experience high rates of internalizing mental health concerns that relate to child adaptive functioning and RRBs, parent ER abilities act as a protective factor against parents' adverse mental health outcomes. Further, mothers in our sample reported significantly higher rates of depression, anxiety, and caregiver strain, as compared with fathers.

Predictors, Parental Views, and Concordance Across Diagnostic Sources of Autism in Male Youth with Fragile X Syndrome: Clinical Best Estimate and Community Diagnoses.

Persons with fragile X syndrome (FXS) with cooccurring autism spectrum disorder (ASD) are at risk for poorer educational, medical, employment, and independent living outcomes. Thus, the identification of ASD in those with FXS is fundamental to ensuring access to appropriate supports to achieve good quality of life. Yet, optimal diagnostic methods and the exact rate of ASD comorbidity remains controversial, and description of ASD identification in the community in FXS has been limited. This study characterized ASD in a sample of 49 male youth with FXS across multiple diagnostic sources: parent-reported community diagnoses, classification derived from ADOS-2 and ADI-R thresholds, and clinical best-estimate classifications from an expert multidisciplinary team. High concordance was found between ADOS-2/ADI-R and clinical best estimate classifications, with both methods supporting ASD in ~ 75% of male youth with FXS. In contrast, 31% had a community diagnosis. Findings supported gross under-identification of ASD in male youth with FXS in community settings; 60% of those who met clinical best estimate criteria for ASD had not received a diagnosis in the community. Moreover, community diagnoses were poorly aligned with the presence of ASD symptoms as perceived by parents and professionals and, unlike clinical best estimate diagnoses, were not associated with cognitive, behavioral, or language features. Findings highlight under-identification of ASD in community settings as a significant barrier to service access for male youth with FXS. Clinical recommendations should emphasize the benefits of seeking a professional ASD evaluation for children with FXS who are noted to display key ASD symptoms.

Consistency and reliability of automated language measures across expressive language samples in autism.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder with substantial clinical heterogeneity, especially in language and communication ability. There is a need for validated language outcome measures that show sensitivity to true change for this population. We used Natural Language Processing to analyze expressive language transcripts of 64 highly-verbal children and young adults (age: 6-23 years, mean 12.8 years; 78.1% male) with ASD to examine the validity across language sampling context and test-retest reliability of six previously validated Automated Language Measures (ALMs), including Mean Length of Utterance in Morphemes, Number of Distinct Word Roots, C-units per minute, unintelligible proportion, um rate, and repetition proportion. Three expressive language samples were collected at baseline and again 4 weeks later. These samples comprised interview tasks from the Autism Diagnostic Observation Schedule (ADOS-2) Modules 3 and 4, a conversation task, and a narration task. The influence of language sampling context on each ALM was estimated using either generalized linear mixed-effects models or generalized linear models, adjusted for age, sex, and IQ. The 4 weeks test-retest reliability was evaluated using Lin's Concordance Correlation Coefficient (CCC). The three different sampling contexts were associated with significantly (P < 0.001) different distributions for each ALM. With one exception (repetition proportion), ALMs also showed good test-retest reliability (median CCC: 0.73-0.88) when measured within the same context. Taken in conjunction with our previous work establishing their construct validity, this study demonstrates further critical psychometric properties of ALMs and their promising potential as language outcome measures for ASD research.

The Autism Symptom Dimensions Questionnaire: Development and psychometric evaluation of a new, open-source measure of autism symptomatology.

AIM: To describe the development and initial psychometric evaluation of a new, freely available measure, the Autism Symptom Dimensions Questionnaire (ASDQ). METHOD: After development and revision of an initial 33-item version, informants completed a revised 39-item version of the ASDQ on 1467 children and adolescents (aged 2-17 years), including 104 with autism spectrum disorder (ASD). RESULTS: The initial 33-item version of the ASDQ had good reliability and construct validity. However, only four specific symptom factors were identified, potentially due to an insufficient number of items. Factor analyses of the expanded instrument identified a general ASD factor and nine specific symptom factors with good measurement invariance across demographic groups. Scales showed good-to-excellent overall and conditional reliability. Exploratory analyses of predictive validity for ASD versus neurotypical and other developmental disability diagnoses indicated good accuracy for population and at-risk contexts. INTERPRETATION: The ASDQ is a free and psychometrically sound informant report instrument with good reliability of measurement across a continuous range of scores and preliminary evidence of predictive validity. The measure may be a useful alternative to existing autism symptom measures but further studies with comparison of clinical diagnoses using criterion-standard instruments are needed. WHAT THIS PAPER ADDS: The Autism Symptom Dimensions Questionnaire (ASDQ) is a new, freely available measure of autism symptoms. The ASDQ showed reliable and accurate measurement of autism symptoms. The measure had good screening efficiency for autism spectrum disorder relative to other developmental conditions.

Exploring the feasibility of collecting multimodal multiperson assessment data via distance in families affected by fragile X syndrome.

INTRODUCTION: Telehealth is an important tool in helping to provide services for hard-to-reach populations. One population that might benefit from telehealth are individuals with fragile X syndrome (FXS). Although FXS is the leading inherited cause of intellectual disability, it is nonetheless a low incidence disorder. Individuals with FXS and their families are involved in research studies, clinical trials and receive interventions - many of which are only offered in a few locations in the United States and thus, not easily accessible to many families. The current project explored the feasibility of using telehealth procedures to collect multimodal behavioural and psychological assessment data from these families. METHODS: Participation in the current study involved online surveys, measures of physiological indices of stress, live interviews and observations of mother-child interactions conducted via distance videoconferencing using the family's own technology when possible. Across all modes of data collection, we obtained information regarding the feasibility of participating entirely via distance by documenting missing data as well as each mother's overall impression of participating via distance. RESULTS: Our telehealth procedures were successfully implemented across a wide range of technology platforms with limited difficulty, and we documented little missing data due to technology-related challenges. Perhaps most importantly, however, our sample of mothers reported high satisfaction with participating via distance. DISCUSSION: These findings suggest that a wide range of services and types of assessments may be amenable to telehealth procedures. Further, the findings have immediate applications as the field shifts towards telehealth due to the coronavirus disease 2019 (COVID-19) pandemic.

The association between expressive language skills and adaptive behavior in individuals with Down syndrome.

The primary goal of this study was to determine whether expressive language skills contribute to adaptive behavior (e.g., socialization and daily living skills) in children, adolescents, and young adults with Down syndrome (DS) whilst controlling for age and nonverbal cognitive ability. Expressive language was assessed using the psychometrically validated Expressive Language Sampling (ELS) conversation and narration procedures. The language produced was transcribed and analyzed to yield measures of expressive vocabulary, syntax, and intelligibility. Socialization and daily living skills of participants with DS were measured with the Vineland Adaptive Behavior Scales, 2nd edition (VABS-2) parent/caregiver rating form. Our results show that the three ELS measures were significantly correlated with multiple measures from the VABS-2 when controlling for age. Several correlations remained significant even when nonverbal cognitive ability was included as a control variable. Our results suggest that expressive language skills contribute to adaptive behavior in children, adolescents, and young adults with DS regardless of age and some of these associations are not explained solely by overall cognitive delays. Further studies including longitudinal data are needed to extend our results.