Modeling Family Dynamics in Children with Fragile X Syndrome

Consensus recommendations on organization of care for individuals with Phelan-McDermid syndrome

The manifestations of Phelan-McDermid syndrome (PMS) are complex, warranting expert and multidisciplinary care in all life stages. In the present paper we propose consensus recommendations on the organization of care for individuals with PMS. We indicate that care should consider all life domains, which can be done within the framework of the International Classification of Functioning, Disability and Health (ICF). This framework assesses disability and functioning as the outcome of the individual's interactions with other factors. The different roles within care, such as performed by a centre of expertise, by regional health care providers and by a coordinating physician are addressed. A surveillance scheme and emergency card is provided and disciplines participating in a multidisciplinary team for PMS are described. Additionally, recommendations are provided for transition from paediatric to adult care. This care proposition may also be useful for individuals with other rare genetic neurodevelopmental disorders.

Modelling triadic relationships in families of children with intellectual disability

Background

Method

Results

Conclusions

Behavior Problems and Social Competence in Fragile X Syndrome: A Systematic Review

Fragile X syndrome (FXS) causes intellectual disability and is the known leading cause of autism. Common problems in FXS include behavior and social problems. Along with syndromic characteristics and autism comorbidity, environmental factors might influence these difficulties. This systematic review focuses on the last 20 years of studies concerning behavior and social problems in FXS, considering environmental and personal variables that might influence both problems. Three databases were reviewed, leading to fifty-one studies meeting the inclusion criteria. Attention deficit hyperactivity disorder (ADHD) problems remain the greatest behavior problems, with behavioral problems and social competence being stable during the 20 years. Some developmental trajectories might have changed due to higher methodological control, such as aggressive behavior and attention problems. The socialization trajectory from childhood to adolescence remains unclear. Comorbidity with autism in individuals with FXS increased behavior problems and worsened social competence profiles. At the same time, comparisons between individuals with comorbid FXS and autism and individuals with autism might help define the comorbid phenotype. Environmental factors and parental characteristics influenced behavior problems and social competence. Higher methodological control is needed in studies including autism symptomatology and parental characteristics. More studies comparing autism in FXS with idiopathic autism are needed to discern differences between conditions.

Childhood intellectual disability and parents' mental health: integrating social, psychological and genetic influences

BACKGROUND

Intellectual disability has a complex effect on the well-being of affected individuals and their families. Previous research has identified multiple risk and protective factors for parental mental health, including socioeconomic circumstances and child behaviour.

AIMS

This study explored whether genetic cause of childhood intellectual disability contributes to parental well-being.

METHOD

Children from across the UK with intellectual disability due to diverse genetic causes were recruited to the IMAGINE-ID study. Primary carers completed the Development and Well-being Assessment, including a measure of parental distress (Everyday Feeling Questionnaire). Genetic diagnoses were broadly categorised into aneuploidy, chromosomal rearrangements, copy number variants (CNVs) and single nucleotide variants.

RESULTS

Compared with the UK general population, IMAGINE-ID parents (n = 888) reported significantly elevated emotional distress (Cohen's d = 0.546). Within-sample variation was related to recent life events and the perceived impact of children's difficulties. Impact was predicted by child age, physical disability, autistic characteristics and other behavioural difficulties. Genetic diagnosis also predicted impact, indirectly influencing parental well-being. Specifically, CNVs were associated with higher impact, not explained by CNV inheritance, neighbourhood deprivation or family structure.

CONCLUSIONS

The mental health of parents caring for a child with intellectual disability is influenced by child and family factors, converging on parental appraisal of impact. We found that genetic aetiologies, broadly categorised, also influence impact and thereby family risks. Recognition of these risk factors could improve access to support for parents, reduce their long-term mental health needs and improve well-being of individuals with intellectual disability.

Telehealth-enabled behavioral treatment for problem behaviors in boys with fragile X syndrome: a randomized controlled trial

Background

Children with fragile X syndrome (FXS) are at increased risk for exhibiting problem behaviors such as aggression and self-injury. However, many children with FXS have limited access to behavioral treatments that have known efficacy due to the low availability of treatment providers and the wide geographical dispersion of families with FXS across the country. Telehealth may offer a cost-effective and practical solution to overcome these significant barriers. We examined the effect of administering an established behavior analytic intervention called functional communication training (FCT) via telehealth on levels of problem behaviors exhibited by boys with FXS. We also examined treatment acceptability, as well as the effect of the treatment on levels of parenting stress.

Methods

Boys with FXS, aged 3 to 10 years, who displayed problem behaviors daily, were randomized to receive FCT via telehealth (n = 30) or treatment as usual (n = 27) over 12 weeks. Outcome measures included in-session observations of problem behavior, the Aberrant Behavior Checklist—Community (ABC-C), the Treatment Acceptability Rating Form—Revised (TARF-R), and the Parenting Stress Index, 4th edition (PSI-4).

Results

Intention-to-treat analyses indicated that scores on the irritability subscale of the ABC-C, our primary outcome measure, decreased significantly for boys who received FCT via telehealth compared to boys who received treatment as usual (p < .001, Cohen’s d = 0.65). In-session observations conducted for those who received treatment showed that levels of problem behavior decreased by 91% from baseline. Levels of parenting stress related to child behavioral problems were also lower following FCT treatment, and caregivers reported that the intervention was acceptable.

Conclusions

These findings support telehealth-enabled FCT as a framework for expanding access to behavioral treatments for problem behaviors in children with FXS. Expanded delivery of behavior analytic treatment via telehealth also has the potential to lower healthcare costs, improve child and family quality of life, and lead to advances in the treatment of problem behavior in the broader population of individuals with neurodevelopmental disorders.

Trial registration

ClinicalTrials.gov, NCT03510156. Registered 27 April 2018

Unaffected siblings of adolescents and adults with fragile X syndrome: Effects on maternal well-being

The present study investigated the effects of children without disabilities on maternal physical and mental health in families with adolescents or adults with fragile X syndrome. Mothers with the FMR1 premutation (N = 87) reported on behavior problems and functional limitations of their adolescent or adult child with fragile X syndrome and their own physical and mental health. Mothers also provided a blood sample to determine FMR1 CGG repeat length. The proportion of unaffected children in the family significantly buffered the effect of both child behavior problems and functional limitations on maternal self-rated health, such that having a higher proportion of unaffected children in the family had a protective effect on maternal health when the target child had more severe behavior problems and functional limitations. There was a similar buffering process for maternal depressive symptoms but at a trend level. Additionally, maternal CGG repeat length had a significant curvilinear association with self-rated health, indicating that mothers with midrange repeat lengths reported the poorest health, whereas mothers with lower and higher repeat lengths in the premutation range reported better health. The data suggest that unaffected children in the family may be an important resource for premutation carrier mothers. Findings are consistent with previous research indicating that mothers with varying levels of genetic liability have variable risk for health problems. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Implications of the FMR1 Premutation for Children, Adolescents, Adults, and Their Families

BACKGROUND AND OBJECTIVES

Given the nature of FMR1 gene expansions, most biological mothers, and often multiple other family members of children with fragile X syndrome (FXS), will have a premutation, which may increase individual and family vulnerabilities. This article summarizes important gaps in knowledge and notes potential implications for pediatric providers with regard to developmental and medical risks for children and adolescents with an FMR1 premutation, including possible implications into adulthood.

METHODS

A structured electronic literature search was conducted on FMR1 pre- and full mutations, yielding a total of 306 articles examined. Of these, 116 focused primarily on the premutation and are included in this review.

RESULTS

Based on the literature review, 5 topic areas are discussed: genetics and epidemiology; phenotypic characteristics of individuals with the premutation; implications for carrier parents of children with FXS; implications for the extended family; and implications for pediatricians.

CONCLUSIONS

Although the premutation phenotype is typically less severe in clinical presentation than in FXS, premutation carriers are much more common and are therefore more likely to be seen in a typical pediatric practice. In addition, there is a wide range of medical, cognitive/developmental, and psychiatric associated features that individuals with a premutation are at increased risk for having, which underscores the importance of awareness on the part of pediatricians in identifying and monitoring premutation carriers and recognizing the impact this identification may have on family members.

Public Health Literature Review of Fragile X Syndrome

OBJECTIVES

The purpose of this systematic literature review is to describe what is known about fragile X syndrome (FXS) and to identify research gaps. The results can be used to help inform future public health research and provide pediatricians with up-to-date information about the implications of the condition for individuals and their families.

METHODS

An electronic literature search was conducted, guided by a variety of key words. The search focused on 4 areas of both clinical and public health importance: (1) the full mutation phenotype, (2) developmental trajectories across the life span, (3) available interventions and treatments, and (4) impact on the family. A total of 661 articles were examined and 203 were included in the review.

RESULTS

The information is presented in the following categories: developmental profile (cognition, language, functional skills, and transition to adulthood), social-emotional profile (cooccurring psychiatric conditions and behavior problems), medical profile (physical features, seizures, sleep, health problems, and physiologic features), treatment and interventions (educational/behavioral, allied health services, and pharmacologic), and impact on the family (family environment and financial impact). Research gaps also are presented.

CONCLUSIONS

The identification and treatment of FXS remains an important public health and clinical concern. The information presented in this article provides a more robust understanding of FXS and the impact of this complex condition for pediatricians. Despite a wealth of information about the condition, much work remains to fully support affected individuals and their families.

Validity of a condition specific outcome measure for fragile X syndrome: the Aberrant Behaviour Checklist-utility index

BACKGROUND

The purpose of this study was to assess the construct validity of the Aberrant Behaviour Checklist-utility index (ABC-UI) by examining the relationship between healthcare resource utilisation by patients with fragile X syndrome (FXS) as well as burden experienced by their caregivers.

METHOD

In 2011, a total of 350 US caregivers of individuals with FXS completed a questionnaire that captured information on FXS-related burden as well as the ABC-Community. Using the ABC-UI, a condition-specific outcome measure derived from the ABC-Community, five utility index categories were created: very low (0.00-0.33); low (0.34-0.66); moderate (0.67-0.77); high (0.78-0.89); and very high (0.90-1.00). Multivariable regression models examined the association between the utility value and nine burden-related outcomes.

RESULTS

Approximately 2% of individuals with FXS were in the very low utility index category, 31% low, 27% moderate, 38% high and 3% very high. The median utility value was 0.74. Women with FXS and adults 18 years and older had higher values. Regression results indicate that individuals with higher utility values were more likely to have fewer specialist visits, use fewer prescription medications, need fewer hours of unpaid caregiving, inflict fewer caregiver injuries and have caregivers with fewer mental health provider visits.

CONCLUSIONS

The ABC-UI appears to function well as condition-specific outcome measure, and as an indicator of health-related quality-of-life and economic burden in individuals with FXS. Among patients with FXS in the US and their caregivers, significant differences in health care resource utilisation and burden exist across health state utility categories.

Psychological Well-Being of Mothers and Siblings in Families of Girls and Women with Rett Syndrome

Few published studies have reported on the psychological well-being of family members of individuals with Rett syndrome (RTT). Eighty-seven mothers of girls and women with RTT completed a questionnaire survey about their daughters' behavioral phenotype, current health, and behavior problems, and their own and a sibling's well-being. Mothers reported increased anxiety but similar levels of depression when compared to a normative sample. Across all problem domains on the Strengths and Difficulties Questionnaire, child and adolescent siblings (n = 39) were reported by mothers to have fewer difficulties than a normative sample. The severity of their daughters' RTT behavioral phenotype predicted increased anxiety and stress for mothers. Increased RTT daughters' current health problems predicted more maternal perceptions of positive gain.

Attributions of Stability, Control and Responsibility: How Parents of Children with Intellectual Disabilities View their Child's Problematic Behaviour and Its Causes

BACKGROUND

Children with intellectual disabilities have high rates of behaviour problems. This study explored parents' causal beliefs and attributions for general problematic child behaviour in children with different aetiologies of intellectual disabilities.

MATERIALS AND METHODS

Ten parents of children with intellectual disabilities participated in interviews about their child's problematic behaviour.

RESULTS

Thematic analysis using NVivo revealed that parents viewed their child's problematic behaviour not only as caused by the child's intellectual disabilities but also by other causes unrelated to the intellectual disabilities, as well as by aspects of the social environmental context. Some causes were viewed as stable and uncontrollable and others as unstable and controllable. In addition, parents showed a strong sense of responsibility for child behaviour.

CONCLUSIONS

Parents of children with intellectual disabilities do not solely interpret their child's problematic behaviour through the intellectual disabilities but incorporate the environment and causes and attributions that are not related to the intellectual disabilities, which may help to promote more effective parenting.

Modeling family adaptation to fragile X syndrome

Using data from a survey of 1,099 families who have a child with Fragile X syndrome, we examined adaptation across 7 dimensions of family life: parenting knowledge, social support, social life, financial impact, well-being, quality of life, and overall impact. Results illustrate that although families report a high quality of life, they struggle with areas such as social support, social life, and parenting knowledge. Path analysis revealed that child and family factors play a role in adaptation, but family resources and social supports moderated their effect on quality of life, well-being, and overall impact. The interrelationship among multiple aspects of family life should be examined to improve family resiliency.

Anxiety, attention problems, hyperactivity, and the Aberrant Behavior Checklist in fragile X syndrome

Behavior problems are a common challenge for individuals with fragile X syndrome (FXS) and constitute the primary clinical outcome domain in trials testing new FXS medications. However, little is known about the relationship between caregiver-reported behavior problems and co-occurring conditions such as anxiety and attention problems. In this study, 350 caregivers, each with at least one son or daughter with full-mutation FXS, rated one of their children with FXS using the Aberrant Behavior Checklist-Community Version (ABC-C); the Anxiety subscale of the Anxiety, Depression, and Mood Scale; and the Attention/Hyperactivity Items from the Symptom Inventories. In addition to examining family consequences of these behaviors, this study also sought to replicate psychometric findings for the ABC-C in FXS, to provide greater confidence for its use in clinical trials with this population. Psychometric properties and baseline ratings of problem behavior were consistent with other recent studies, further establishing the profile of problem behavior in FXS. Cross-sectional analyses suggest that selected dimensions of problem behavior, anxiety, and hyperactivity are age related; thus, age should serve as an important control in any studies of problem behavior in FXS. Measures of anxiety, attention, and hyperactivity were highly associated with behavior problems, suggesting that these factors at least coincide with problem behavior. However, these problems generally did not add substantially to variance in caregiver burden predicted by elevated behavior problems. The results provide further evidence of the incidence of problem behaviors and co-occurring conditions in FXS and the impact of these behaviors on the family.

FRAGILE X SYNDROME: PSYCHIATRIC MANIFESTATIONS, ASSESSMENT AND EMERGING THERAPIES

Fragile X Syndrome (FXS), the most common inherited cause of intellectual disabilities, is an X-linked dominant disorder caused by the amplification of a CGG repeat in the 5' untranslated region of the fragile X mental retardation gene 1 (FMR1). Prevalence estimates of the disorder are approximately 1/3600. Psychiatric manifestations of the disorder include anxiety, attention deficit hyperactivity disorder, autism, mood instability and aggression. In this article we review the above psychiatric manifestations and challenges to accurate assessment. We also discuss how the neurobiological underpinnings of these symptoms are beginning to be understood and can help guide treatment.

Health and economic consequences of fragile X syndrome for caregivers

OBJECTIVE

To describe the health and economic burden experienced by caregivers of individuals with fragile X syndrome (FXS) and test the assumption that burden is associated with specific dimensions of problem behavior.

METHODS

Three hundred fifty caregivers rated their son or daughter's problem behavior and reported the use of medical services, caregiving time, impact on employment, financial burden, caregiver injuries, caregiver mental health, and prescription drug use.

RESULTS

The son's FXS posed a significant burden for caregivers in a number of areas. Visits to medical specialists were common for both males (5.4 per year) and females (5.1 per year). Caregivers reported 9.2 hours per day of family caregiving for males with FXS and an additional 5.5 hours of paid help. Most families reported that FXS had at least some financial impact on the family, and caregivers had to take an average of 19.4 hours from work each month to care for their child's needs. Almost one third of the caregivers had been injured by their child at least once in the past year; when injuries occurred, the frequency was high (14.7 per year), of which 2.7 required medical care. Approximately one third of the caregivers had seen a professional for anxiety, stress, or depression during the past year, and one fourth were taking medication to help with these symptoms. Caregiver burden was highly associated with problem behavior, most commonly irritability.

CONCLUSION

Problem behavior is a strong contributor to burden experienced by caregivers of children and adults with FXS. Clinicians should be aware of the role problem behavior plays in family adaptation and help families access appropriate medical and social support services.

Behaviour problems, maternal internalising symptoms and family relations in families of adolescents and adults with fragile X syndrome

BACKGROUND

Studies have linked the behaviour problems of children with fragile X syndrome (FXS) to maternal well-being, but less is known about how behaviour problems relate to important family factors such as marital satisfaction and family cohesion.

METHODS

Married mothers of 115 adolescents and adults with FXS completed questionnaires and interviews, and maternal CGG repeat length was obtained by medical/laboratory records or by blood analysis.

RESULTS

Indirect effects were present between behaviour problems and family variables in that behaviour problems were positively related to maternal internalising symptoms which were, in turn, negatively associated with both family cohesion and marital satisfaction. Direct associations between behaviour problems and family relationship variables were not significant.

CONCLUSIONS

Findings suggest the importance of intervening with behaviour problems in individuals with FXS and identify maternal mental health as a potentially powerful conduit for the effects of child behaviour on relationships within these families. Implications for targeted interventions are discussed.

Delineation of behavioral phenotypes in genetic syndromes: characteristics of autism spectrum disorder, affect and hyperactivity

We investigated autism spectrum disorder (ASD) symptomatology, hyperactivity and affect in seven genetic syndromes; Angelman (AS; n = 104), Cri du Chat (CdCS; 58), Cornelia de Lange (CdLS; 101), Fragile X (FXS; 191), Prader-Willi (PWS; 189), Smith-Magenis (SMS; 42) and Lowe (LS; 56) syndromes (age range 4-51). ASD symptomatology was heightened in CdLS and FXS. High levels of impulsivity were seen in SMS, AS, CdCS, FXS and adults with CdLS. Negative affect was prominent in adults with CdLS, while positive affect was prominent in adults with AS and FXS. Heightened levels of overactivity and impulsivity were identified in FXS, AS and SMS while low levels were identified in PWS. These findings confirm and extend previously reported behavioral phenotypes.

Mood and anxiety disorders in females with the FMR1 premutation

Fragile X syndrome (FXS) is a model for studying the relative contributions of genetic and environmental factors to psychiatric disorders in mothers of children with disabilities. Here, we examine the frequency and predictors of mood and anxiety disorders in mothers with the FMR1 premutation. Ninety-three females with the FMR1 premutation were in the study and were compared to 2,159 women from the National Comorbidity Survey Replication (NCS-R) dataset. Mood and anxiety disorders were assessed using the SCID-I. Our data reflect elevated lifetime major depressive disorder (MDD), lifetime panic disorder without agoraphobia and current agoraphobia without panic disorder in the FMR1 premutation sample. Also, we found a low frequency of lifetime social phobia, specific phobia, and post-traumatic stress disorders and current specific phobia in the FMR1 premutation sample. The profile of MDD in the FMR1 premutation sample was not episodic or comorbid with an anxiety disorder, as in the NCS-R dataset. Never having been married and smaller CGG repeat length were associated with increased likelihood of MDD while increased children with FXS in the family and greater child problem behaviors were associated with increased likelihood of an anxiety disorder in the FMR 1 premutation group. Major depression in females with the FMR1 premutation may not be characterized as an episodically chronic recurrent disorder as it is in community samples and may have a genetic basis given the relationship with CGG repeat length and lack of association with all child and most demographic factors.

Longitudinal changes in intellectual development in children with Fragile X syndrome

Structural equation modeling (SEM) was used to examine the development of intellectual functioning in 145 school-age pairs of siblings. Each pair included one child with Fragile X syndrome (FXS) and one unaffected sibling. All pairs of children were evaluated on the Wechsler Intelligence Scale for Children-Third Edition (WISC-III) at time 1 and 80 pairs of children received a second evaluation at time 2 approximately 4 years later. Compared to their unaffected siblings, children with FXS obtained significantly lower percentage correct scores on all subtests of the WISC at both time points. During the time between the first and second assessments, the annual rate of intellectual development was approximately 2.2 times faster in the unaffected children compared to the children with FXS. Levels of the fragile X mental retardation protein (FMRP) were highly associated with intellectual ability scores of the children with FXS at both time points (r=0.55 and 0.64 respectively). However, when gender, age, and the time between assessments were included as covariates in the structural equation model, FMRP accounted for only 5% of the variance in intellectual ability scores at time 1 and 13% of the variance at time 2. The results of this study suggest that slower learning contributes to the low and declining standardized IQ scores observed in children with FXS.

The role of maternal responsivity in the development of children with intellectual disabilities

There is growing evidence that cumulative exposure to highly responsive parenting styles throughout the early childhood period may provide a variety of important child benefits in terms of language, cognitive, social, and emotional development. We view maternal responsivity as a dynamic construct of central importance to the development of children with intellectual disabilities just as it is for typically developing children. In this study, we selectively review the theoretical and conceptual evidence for the effects of responsivity on development, discuss factors known to influence responsivity including the nature of a child's disability, and review intervention approaches intended to enhance maternal responsivity. We conclude with a set of recommendations for future research.