Adapting a measure of gross motor skills for individuals with CDKL5 deficiency disorder: A psychometric study

PURPOSE

Validated measures capable of demonstrating meaningful interventional change in the CDKL5 deficiency disorder (CDD) are lacking. The study objective was to modify the Rett Syndrome Gross Motor Scale (RSGMS) and evaluate its psychometric properties for individuals with CDD.

METHODS

Item and scoring categories of the RSGMS were modified. Caregivers registered with the International CDKL5 Clinical Research Network uploaded motor videos filmed at home to a protected server and completed a feedback questionnaire (n = 70). Rasch (n = 137), known groups (n = 109), and intra- and inter-rater reliability analyses (n = 50) were conducted.

RESULTS

The age of individuals with CDD ranged from 1.5 to 34.1 years. The modified scale, Gross Motor-Complex Disability (GM-CD), comprised 17 items. There were no floor or ceiling effects and inter- and intra-rater reliability were good. Rasch analysis demonstrated that the items encompassed a large range of performance difficulty, although there was some item redundancy and some disordered categories. One item, Prone Head Position, was a poor fit. Caregiver-reported acceptability was positive. Scores differed by age and functional abilities.

SUMMARY

GM-CD appears to be a suitable remotely administered measure and psychometrically sound for individuals with CDD. This study provides the foundation to propose the use of GM-CD in CDD clinical trials. Longitudinal evaluation is planned.

Dental procedures in children with or without intellectual disability and autism spectrum disorder in a hospital setting

BACKGROUND

This population-based cohort study investigated dental procedures in the hospital setting in Western Australian children with or without intellectual disability (ID) and/or autism spectrum disorder (ASD) aged up to 18 years. Considering previously reported disparities in dental disease between Indigenous and non-Indigenous Australian children, this study also investigated the effect of Indigenous status on dental procedures.

METHODS

Data on Western Australian live births from 1983 to 2010 from the Midwives Notification System were linked to the Intellectual Disability Exploring Answers database and the Hospital Morbidity Data collection. Primary admissions for relevant dental diagnoses were identified, and treatment procedures for dental hospitalization were investigated. Descriptive statistics and Pearson's chi-squared test of independence were used for analysis.

RESULTS

Overall, 76 065 episodes of dental hospitalization were recorded. Amongst children with ID and/or ASD, Indigenous children experienced more extractions and fewer restorations (68.7% and 16.2%) compared to non-Indigenous children (51.5% and 25.9%). After 6 years, extraction occurred less often in children with ID and/or ASD than in those without, where most surgical dental extractions were in the age group of 13-18 years.

CONCLUSIONS

This study indicates a need for further improvements in access to dental services and the quality of care provided in hospitals for children with ID/ASD. There is also concern that more vulnerable Indigenous and all disadvantaged children are receiving an inadequate level of dental services resulting in more emergency dental hospitalization and invasive treatment.

Correction to: Large‑scale pathway specific polygenic risk and transcriptomic community network analysis identifies novel functional pathways in Parkinson disease

A correction to this paper has been published: https://doi.org/10.1007/s00401-021-02309-z

Epithelioid hemangioendothelioma, an ultra-rare cancer: a consensus paper from the community of experts

Epithelioid hemangioendothelioma (EHE) is an ultra-rare, translocated, vascular sarcoma. EHE clinical behavior is variable, ranging from that of a low-grade malignancy to that of a high-grade sarcoma and it is marked by a high propensity for systemic involvement. No active systemic agents are currently approved specifically for EHE, which is typically refractory to the antitumor drugs used in sarcomas. The degree of uncertainty in selecting the most appropriate therapy for EHE patients and the lack of guidelines on the clinical management of the disease make the adoption of new treatments inconsistent across the world, resulting in suboptimal outcomes for many EHE patients. To address the shortcoming, a global consensus meeting was organized in December 2020 under the umbrella of the European Society for Medical Oncology (ESMO) involving >80 experts from several disciplines from Europe, North America and Asia, together with a patient representative from the EHE Group, a global, disease-specific patient advocacy group, and Sarcoma Patient EuroNet (SPAEN). The meeting was aimed at defining, by consensus, evidence-based best practices for the optimal approach to primary and metastatic EHE. The consensus achieved during that meeting is the subject of the present publication.

•

This consensus paper provides key recommendations on the management of epithelioid hemangioendothelioma (EHE).

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Recommendations followed a consensus meeting between experts and a representative of the EHE advocacy group and SPAEN.

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Authorship includes a multidisciplinary group of experts from different institutions from Europe, North America and Asia.

Oral health care and service utilisation in individuals with Rett syndrome: an international cross-sectional study

BACKGROUND

There is a dearth of literature available on the comparative oral health status of those with Rett syndrome (RTT) despite diurnal bruxism being a supportive diagnostic criterion for the disorder. This study was designed to investigate the dental experiences of individuals with RTT in terms of perceived at-home and professional dental care.

METHODS

Using data in the InterRett database, provided by English-speaking families of individuals with a confirmed MECP2 genetic mutation, the study investigated relationships between dental problems, oral care, child factors including bruxism and use of gastrostomy, and socioeconomic indicators. The study also explored relationships between dental presentations and socioeconomic, child, and family-related factors.

RESULTS

Individuals with RTT exhibiting bruxism were more likely to access dental treatment. Those who had full oral feeding had a higher incidence rate of dental treatment than those with full tube feeding. A conservative (under) estimation of the overall dental caries progression rate revealed that this may be similar to that of the normal population.

CONCLUSIONS

Drivers for dental treatment in RTT include bruxism as well as dental caries. Those who have full oral feeding experience more dental treatment than those with full tube feeding. A higher maternal education level may confer a protective effect for oral health outcomes in those with RTT. Nevertheless, families generally tended to value the importance of oral health despite reported difficulties in day-to-day mouth care.

Large-scale pathway specific polygenic risk and transcriptomic community network analysis identifies novel functional pathways in Parkinson disease

Polygenic inheritance plays a central role in Parkinson disease (PD). A priority in elucidating PD etiology lies in defining the biological basis of genetic risk. Unraveling how risk leads to disruption will yield disease-modifying therapeutic targets that may be effective. Here, we utilized a high-throughput and hypothesis-free approach to determine biological processes underlying PD using the largest currently available cohorts of genetic and gene expression data from International Parkinson's Disease Genetics Consortium (IPDGC) and the Accelerating Medicines Partnership-Parkinson's disease initiative (AMP-PD), among other sources. We applied large-scale gene-set specific polygenic risk score (PRS) analyses to assess the role of common variation on PD risk focusing on publicly annotated gene sets representative of curated pathways. We nominated specific molecular sub-processes underlying protein misfolding and aggregation, post-translational protein modification, immune response, membrane and intracellular trafficking, lipid and vitamin metabolism, synaptic transmission, endosomal-lysosomal dysfunction, chromatin remodeling and apoptosis mediated by caspases among the main contributors to PD etiology. We assessed the impact of rare variation on PD risk in an independent cohort of whole-genome sequencing data and found evidence for a burden of rare damaging alleles in a range of processes, including neuronal transmission-related pathways and immune response. We explored enrichment linked to expression cell specificity patterns using single-cell gene expression data and demonstrated a significant risk pattern for dopaminergic neurons, serotonergic neurons, hypothalamic GABAergic neurons, and neural progenitors. Subsequently, we created a novel way of building de novo pathways by constructing a network expression community map using transcriptomic data derived from the blood of PD patients, which revealed functional enrichment in inflammatory signaling pathways, cell death machinery related processes, and dysregulation of mitochondrial homeostasis. Our analyses highlight several specific promising pathways and genes for functional prioritization and provide a cellular context in which such work should be done.

Survival of children and adolescents with intellectual disability following gastrostomy insertion

BACKGROUND

Positive health outcomes have been observed following gastrostomy insertion in children with intellectual disability, which is being increasingly used at younger ages to improve nutritional intake. This study investigated the effect of gastrostomy insertion on survival of children with severe intellectual disability.

METHODS

We used linked disability and health data of children and adolescents who were born in Western Australia between 1983 and 2009 to compare survival of individuals with severe intellectual disability by exposure to gastrostomy status. For those born in 2000-2009, we employed propensity score matching to adjust for confounding by indication. Effect of gastrostomy insertion on survival was compared by pertinent health and sociodemographic risk factors.

RESULTS

Compared with children born in the 1980s-1990s, probability of survival following first gastrostomy insertion for those born in 2000-2009 was higher (2 years: 94% vs. 83%). Mortality risk was higher in cases than that in their matched controls (hazard ratio 2.9, 95% confidence interval 1.1, 7.3). The relative risk of mortality (gastrostomy vs. non-gastrostomy) may have differed by sex, birthweight and time at first gastrostomy insertion. Respiratory conditions were a common immediate or underlying cause of death among all children, particularly among those undergoing gastrostomy insertion.

CONCLUSIONS

Whilst gastrostomy insertion was associated with lower survival rates than children without gastrostomy, survival improved with time, and gastrostomy afforded some protection for the more vulnerable groups, and earlier use appears beneficial to survival. Specific clinical data that may be used to prioritise the need for gastrostomy insertion may be responsible for the survival differences observed.

Oral health experiences of individuals with Rett syndrome: a retrospective study

Background

There is relatively little literature on the oral health experiences of individuals with Rett syndrome. This study described the incidence of dental extractions and restorations in a population-based cohort, according to a range of demographic and clinical factors. The association between bruxism and age was also investigated.

Methods

Existing questionnaire data in the population-based Australian Rett Syndrome Database for the years 2004, 2006, 2009 or 2011 on genetically confirmed female cases (n = 242) were analysed.

Results

The incidence rate of restorations and extractions were 6.8 per 100 person years (py) and 9.3 per 100 py respectively. The incidence of extractions decreased with increasing levels of income. Compared to those with a C-terminal mutation, the incidence rate of extraction was higher for those with large deletions (Incidence Rate Ratio (IRR) 4.93; 95% CI 1.46–16.7, p = 0.01). There was a 5% decrease in the risk of frequent bruxism for every one-year increase in age (Risk Ratio 0.95; 95% CI 0.94–0.97).

Conclusions

Social advantage may provide some protection for dental health in individuals with Rett syndrome. Those with more severe genotypes seemed to have poorer oral health outcomes.

Exploring quality of life of children with cerebral palsy and intellectual disability: What are the important domains of life?

BACKGROUND

Although it is estimated that half of all children with cerebral palsy also have comorbid intellectual disability, the domains of quality of life (QOL) important for these children are not well understood. The aim of this study was to identify important domains of QOL for these children and adolescents.

METHODS

Due to the children's communication impairments, qualitative semi-structured interviews were conducted with 18 parents. The children (9 males) had a median age of 12 (range 7 to 17) years at interview and nearly two thirds were classified as Gross Motor Function Classification System IV or V. A grounded theory approach was used to identify domains of QOL.

RESULTS

The 11 domains identified as important to QOL were physical health, body comfort, behaviour and emotion, communication, predictability and routine, movement and physical activity, nature and outdoors, variety of activity, independence and autonomy, social connectedness, and access to services.

CONCLUSIONS

The domains of QOL that emerged from this study will be useful for professionals who support children with cerebral palsy and their families. They will also be important for developing a QOL instrument essential for informing the development of interventions and their monitoring and evaluation.

Risk of stillbirth, preterm delivery, and fetal growth restriction following exposure in a previous birth: systematic review and meta-analysis

BACKGROUND

Little is known about the risk of non-recurrent adverse birth outcomes.

OBJECTIVES

To evaluate the risk of stillbirth, preterm birth (PTB), and small for gestational age (SGA) as a proxy for fetal growth restriction (FGR) following exposure to one or more of these factors in a previous birth.

SEARCH STRATEGY

We searched MEDLINE, EMBASE, Maternity and Infant Care, and Global Health from inception to 30 November 2016.

SELECTION CRITERIA

Studies were included if they investigated the association between stillbirth, PTB, or SGA (as a proxy for FGR) in two subsequent births.

DATA COLLECTION AND ANALYSIS

Meta-analysis and pooled association presented as odds ratios (ORs) and adjusted odds ratios (aORs).

MAIN RESULTS

Of the 3399 studies identified, 17 met the inclusion criteria. A PTB or SGA (as a proxy for FGR) infant increased the risk of subsequent stillbirth ((pooled OR 1.70; 95% confidence interval, 95% CI, 1.34-2.16) and (pooled OR 1.98; 95% CI 1.70-2.31), respectively). A combination of exposures, such as a preterm SGA (as a proxy for FGR) birth, doubled the risk of subsequent stillbirth (pooled OR 4.47; 95% CI 2.58-7.76). The risk of stillbirth also varied with prematurity, increasing three-fold following PTB <34 weeks of gestation (pooled OR 2.98; 95% CI 2.05-4.34) and six-fold following preterm SGA (as a proxy for FGR) <34 weeks of gestation (pooled OR 6.00; 95% CI 3.43-10.49). A previous stillbirth increased the risk of PTB (pooled OR 2.82; 95% CI 2.31-3.45), and subsequent SGA (as a proxy for FGR) (pooled OR 1.39; 95% CI 1.10-1.76).

CONCLUSION

The risk of stillbirth, PTB, or SGA (as a proxy for FGR) was moderately elevated in women who previously experienced a single exposure, but increased between two- and three-fold when two prior adverse outcomes were combined. Clinical guidelines should consider the inter-relationship of stillbirth, PTB, and SGA, and that each condition is an independent risk factor for the other conditions.

TWEETABLE ABSTRACT

Risk of adverse birth outcomes in next pregnancy increases with the combined number of previous adverse events.

PLAIN LANGUAGE SUMMARY

Why and how was the study carried out? Each year, around 2.6 million babies are stillborn, 15 million are born preterm (<37 weeks of gestation), and 32 million are born small for gestational age (less than tenth percentile for weight, smaller than usually expected for the relevant pregnancy stage). Being born preterm or small for gestational age can increase the chance of long-term health problems. The effect of having a stillbirth, preterm birth, or small-for-gestational-age infant in a previous pregnancy on future pregnancy health has not been summarised. We identified 3399 studies of outcomes of previous pregnancies, and 17 were summarised by our study. What were the main findings? The outcome of the previous pregnancy influenced the risk of poor outcomes in the next pregnancy. Babies born to mothers who had a previous preterm birth or small-for-gestational-age birth were more likely to be stillborn. The smaller and the more preterm the previous baby, the higher the risk of stillbirth in the following pregnancy. The risk of stillbirth in the following pregnancy was doubled if the previous baby was born both preterm and small for gestational age. Babies born to mothers who had a previous stillbirth were more likely to be preterm or small for gestational age. What are the limitations of the work? We included a small number of studies, as there are not enough studies in this area (adverse birth outcomes followed by adverse cross outcomes in the next pregnancy). We found very few studies that compared the risk of small for gestational age after preterm birth or stillbirth. Definitions of stillbirth, preterm birth categories, and small for gestational age differed across studies. We did not know the cause of stillbirth for most studies. What are the implications for patients? Women who have a history of poor pregnancy outcomes are at greater risk of poor outcomes in following pregnancies. Health providers should be aware of this risk when treating patients with a history of poor pregnancy outcomes.

Expanding the clinical picture of the MECP2 Duplication syndrome

Individuals with two or more copies of the MECP2 gene, located at Xq28, share clinical features and a distinct facial phenotype known as MECP2 Duplication syndrome. We have examined perinatal characteristics, early childhood development and medical co-morbidities in this disorder. The International Rett Syndrome Phenotype Database (InterRett), which collects information from caregivers and clinicians on individuals with Rett syndrome and MECP2 associated disorders, was used as the data source. Data were available on 56 cases (49 males and 7 females) with MECP2 Duplication syndrome. Median age at ascertainment was 7.9 years (range: 1.2-37.6 years) and at diagnosis 3.0 years (range: 3 weeks-37 years). Less than a third (29%) learned to walk. Speech deterioration was reported in 34% and only 20% used word approximations or better at ascertainment. Over half (55%) had been hospitalised for respiratory infections in the first 2 years of life. Just under half (44%) had seizures, occurring daily in nearly half of this group. The majority (89%) had gastrointestinal problems and a third had a gastrostomy. Following the recent demonstration of phenotype reversal in a mouse model of MECP2 Duplication, a clear understanding of the natural history is crucial to the design and implementation of future therapeutic strategies.

ViPAR: a software platform for the Virtual Pooling and Analysis of Research Data

Background: Research studies exploring the determinants of disease require sufficient statistical power to detect meaningful effects. Sample size is often increased through centralized pooling of disparately located datasets, though ethical, privacy and data ownership issues can often hamper this process. Methods that facilitate the sharing of research data that are sympathetic with these issues and which allow flexible and detailed statistical analyses are therefore in critical need. We have created a software platform for the Virtual Pooling and Analysis of Research data (ViPAR), which employs free and open source methods to provide researchers with a web-based platform to analyse datasets housed in disparate locations.

Methods: Database federation permits controlled access to remotely located datasets from a central location. The Secure Shell protocol allows data to be securely exchanged between devices over an insecure network. ViPAR combines these free technologies into a solution that facilitates ‘virtual pooling’ where data can be temporarily pooled into computer memory and made available for analysis without the need for permanent central storage.

Results: Within the ViPAR infrastructure, remote sites manage their own harmonized research dataset in a database hosted at their site, while a central server hosts the data federation component and a secure analysis portal. When an analysis is initiated, requested data are retrieved from each remote site and virtually pooled at the central site. The data are then analysed by statistical software and, on completion, results of the analysis are returned to the user and the virtually pooled data are removed from memory.

Conclusions: ViPAR is a secure, flexible and powerful analysis platform built on open source technology that is currently in use by large international consortia, and is made publicly available at [ http://bioinformatics.childhealthresearch.org.au/software/vipar/ ].

Functioning and post-school transition outcomes for young people with Down syndrome

AIM

To investigate the relationship between functioning and post-school day occupation for young adults with Down syndrome.

METHODS

Families of young people with Down syndrome (n = 269) aged 15-30 years in 2009 were recruited from the population-based Down syndrome 'Needs Opinion Wishes' database in Western Australia. Questionnaires were mailed to participating families and involved two parts, young person characteristics and family functioning; 203 were returned (75%). Of those families who returned questionnaires, 164 (80.8%) of their young adults had left school. Participation in post-school day occupations was the main outcome and included; open employment, training, sheltered employment or alternatives to employment (ATE).

RESULTS

Young adults were reported as participating in open employment (n = 42), training (n = 17), sheltered employment (n = 64) or ATE (n = 41) post-school. Those who reported better functioning in self-care, community and communication skills were more likely to be in open employment and/or attending Technical and Further Education compared with those attending sheltered employment and/or ATE after adjusting for age, gender and rural/metropolitan regions. Current health as measured by visits to a general practitioner (GP) and hospitalizations revealed a weak relationship with post-school day occupations, with increasing likelihood of participating in open employment or training with increasing hospitalizations and GP visits.

CONCLUSIONS

Our analysis shows that functioning in activities of daily living was related to post-school day occupation. Current health status and behaviour were found to have a weak relationship with post-school day occupation adjusting for functioning in the final model.

Changes in risk factors for preterm birth in Western Australia 1984-2006

OBJECTIVE

To characterise changing risk factors of preterm birth in Western Australia between 1984 and 2006.

DESIGN

Population-based study.

SETTING

Western Australia.

POPULATION

All non-Aboriginal women giving birth to live singleton infants between 1984 and 2006.

METHODS

Multinomial, multivariable regression models were used to assess antecedent profiles by preterm status and labour onset types (spontaneous, medically indicated, prelabour rupture of membranes [PROM]). Population attributable fraction (PAF) estimates characterized the contribution of individual antecedents as well as the overall contribution of two antecedent groups: pre-existing medical conditions (including previous obstetric history) and pregnancy complications.

MAIN OUTCOME MEASURE

Antecedent relationships with preterm birth, stratified by labour onset type.

RESULTS

Marked increases in maternal age and primiparous births were observed. A four-fold increase in the rates of pre-existing medical complications over time was observed. Rates of pregnancy complications remained stable. Multinomial regression showed differences in antecedent profiles across labour onset types. PAF estimates indicated that 50% of medically indicated preterm deliveries could be eliminated after removing six antecedents from the population; estimates for PROM and spontaneous preterm reduction were between 10 and 20%. Variables pertaining to previous and current obstetric complications (previous preterm birth, previous caesarean section, pre-eclampsia and antepartum haemorrhage) were the most influential predictors of preterm birth and adverse labour onset (PROM and medically indicated).

CONCLUSIONS

Preterm antecedent profiles have changed markedly over the 23 years studied. Some changes may be attributable to true change, others to advances in surveillance and detection. Still others may signify change in clinical practice.

Dental admissions in children under two years--a total-population investigation

BACKGROUND

There is a lack of literature describing dental admissions in children particularly very young children. This paper describes dental and oral cavity admissions and associated factors in children under two years of age using total-population databases.

METHODS

The data used for this study were extracted from population-based databases which are linkable with midwives' data collected on all births in Western Australia. Children born from 1980 to 1998 inclusive (n = 459,831) were followed until two years of age including data on deaths, hospital admissions, birth defects and intellectual disability. Dental admissions (by ICD-9 category) and associated factors were investigated.

RESULTS

There were 1513 dental admissions occurring in 1459 of the children up to the age of two years. Children were most frequently admitted under ICD-9 category 521, which includes a hospital admission for dental caries (39% of all oral cavity admissions), followed by ICD-9 category 528 (29%), which includes diseases of the oral soft tissues. Univariate analysis indicated that those with intellectual disability (OR 2.10, 95%CI 1.40-3.16), birth defect (1.74, 1.45-2.09), residing in a region without fluoridated water (2.15, 1.72-2.69) being male (1.14, 1.03-1.26), those from rural areas (2.29, 2.07-2.54) and Indigenous children (4.45, 3.91-5.05) were significantly more likely to have had a dental admission.

CONCLUSION

Using total-population data allowed us to describe the admissions in children under two years and associated factors while able to identify children with intellectual disability or birth defects.

Family functioning in families with a child with Down syndrome: a mixed methods approach

BACKGROUND

This study aimed to explore the factors that predict functioning in families with a child with Down syndrome using a mixed methods design. The quantitative component examined the effect of maladaptive and autism-spectrum behaviours on the functioning of the family while the qualitative component explored the impact of having a child with Down syndrome on family holidays, family activities and general family functioning.

METHODS

Participants in this study were 224 primary caregivers of children with Down syndrome aged 4-25 years (57.1% male; 42.9% female) currently residing in Western Australia (74.0% in metropolitan Perth and 26.0% in rural Western Australia).

RESULTS

Maladaptive and autism-spectrum behaviour were associated with poorer family functioning. Mean total scores on the measures of family functioning and marital adjustment were comparable to that of families of typically developing children. Consistent with the quantitative findings, normality was the most common theme to emerge in the qualitative data. Child problem behaviours were also identified by parents/carers as having a negative impact on the family.

CONCLUSIONS

This study has implications for the development of programs to support families with a child with Down syndrome and may dispel some of the myths surrounding the impact of intellectual disability on the family.

Total population investigation of dental hospitalizations in indigenous children under five years in Western Australia using linked data

BACKGROUND

The aim of this study was to compare dental hospital admissions in a total state birth population of Indigenous and non-Indigenous children aged under five years in Western Australia.

METHODS

Midwives' notification data were linked to databases of deaths, admissions, birth defects and intellectual disability. Births during 1980-1995 were followed until five years of age (n = 383,665). Dental admissions were classified by ICD-9 principal diagnosis categories.

RESULTS

There were 738 dental admissions for 665 children aged up to five years of Indigenous mothers (n = 20,921). Indigenous children comprised 6.3% of all children having a dental admission in this age group; 3.2% of children with Indigenous mothers had a dental admission compared with 2.7% of non-Indigenous children. Overall, 8.7% (n = 58) of Indigenous children with a dental admission had a birth defect and 5.5% (n = 23) had an intellectual disability (compared to 8.8% and 3.2%). Indigenous children were four times more likely to be diagnosed with oral soft tissue diseases than non-Indigenous children, and less likely to be categorized as having diseases of the dental hard tissues. Indigenous children were more likely to have a longer dental admission.

CONCLUSIONS

These analyses provide important findings regarding hospital admissions for Indigenous children. Admissions for disorders of the soft tissues are more common in Indigenous children.

What does the nature of the MECP2 mutation tell us about parental origin and recurrence risk in Rett syndrome?

The MECP2 mutations occurring in the severe neurological disorder Rett syndrome are predominantly de novo, with rare familial cases. The aims of this study were to provide a precise estimate of the parental origin of MECP2 mutations using a large Chinese sample and to assess whether parental origin varied by mutation type. The parental origin was paternal in 84/88 [95.5%, (95% confidence interval 88.77-98.75)] of sporadic Chinese cases. However, in a pooled sample including data from the literature the spectrum of mutations occurring on maternally and paternally derived chromosomes differed significantly. The excess we found of 'single base pair gains or losses' on maternally derived MECP2 gene alleles suggests that this mutational category is associated with an elevated risk of gonadal mosaicism, which has implications for genetic counseling.

Evaluation of the processes of family-centred care for young children with intellectual disability in Western Australia

INTRODUCTION

Government early intervention services for children with intellectual disability (ID) in Western Australia have adopted the model of family-centred care. The aim of this study was to evaluate how well it was being practised, to describe the pattern of service utilization and to identify factors influencing parental perceptions of family-centred care.

METHODS

The study included children aged 0-6 years with ID, who were registered clients of Disability Services Commission, Western Australia. Parents completed a postal survey questionnaire about the frequency and type of services received and their perceptions of services using the Measure of Processes of Care (MPOC-56) questionnaire. Mean scores for the five MPOC domains were compared using anova against the independent variables of child age group, child diagnostic group, service type and frequency, place of residence, family and demographic variables. Significant variables in each domain were then entered into multivariate analyses.

RESULTS

Of 292 eligible families, 165 (59%) returned a completed questionnaire. While over 50% of children had contact with occupational, speech and physical therapists at least once per month, less than 20% of children had at least annual contact with either psychology or dental services. Families rated their satisfaction highest for 'respectful and supportive care' and lowest for 'providing general information'. Individual item analyses indicated less satisfaction with 'co-ordinated and comprehensive care'. Higher means were associated with more frequent contact with occupational therapy.

CONCLUSION

Overall respondents reported early intervention services for young children with ID in Western Australia provided satisfactory family-centred care by means of the 56-item MPOC. The frequency of contact with allied health professionals was positively associated with parental ratings of family-centred care. The study indicates under-servicing in dental care and psychology services.

Valproate and risk of fracture in Rett syndrome

OBJECTIVES

Some associations between antiepileptic drugs (AEDs) and fracture risk have been reported in the general population. This study investigated the relationships between fracture risk and commonly used AEDs in Rett syndrome, a genetic disorder associated with intellectual and physical disability.

STUDY DESIGN

Cases (n=233) were sourced from the population-based Australian Rett Syndrome Database and longitudinal data were used. The Cox proportional hazard model was used to analyse relationships between fracture and prescribed AEDs, mobility, epilepsy diagnosis and genotype.

RESULTS

After controlling for mobility, epilepsy diagnosis and genotype, use of valproate increased the risk of fracture threefold after at least 1 year (HR 3.56; 95% CI 1.85 to 6.82) and after 2 or more years (HR 3.02; 95% CI 1.90 to 4.80). There was a lesser increased risk (HR 1.99; 95% CI 0.99 to 4.02) with lamotrigine in the first year of use but not for subsequent years of use. Carbamazepine slightly decreased the risk (HR 0.60; 95% CI 0.35 to 1.02) after 2 or more years of use.

CONCLUSIONS

The effect of valproate on bone health should be considered when managing epilepsy in Rett syndrome. Multiple mechanisms could be contributing to this effect.

Updating the profile of C-terminal MECP2 deletions in Rett syndrome

OBJECTIVES

This study aimed to compare the phenotype of Rett syndrome cases with C-terminal deletions to that of cases with different MECP2 mutations and to examine the phenotypic variation within C-terminal deletions.

METHODS

Cases were selected from InterRett, an international database and from the population-based Australian Rett Syndrome Database. Cases (n=832) were included if they had a pathogenic MECP2 mutation in which the nature of the amino acid change was known. Three severity scale systems were used, and individual aspects of the phenotype were also compared.

RESULTS

Lower severity was associated with C-terminal deletions (n=79) compared to all other MECP2 mutations (e.g. Pineda scale C-terminals mean 15.0 (95% CI 14.0-16.0) vs 16.2 (15.9-16.5). Cases with C-terminal deletions were more likely to have a normal head circumference (odds ratio 3.22, 95% CI 1.53 - 6.79) and weight (odds ratio 2.97, 95% CI 1.25-5.76). Onset of stereotypies tended to be later (median age 2.5 years vs 2 years, p<0.001 from survival analysis), and age of learning to walk tended to be earlier (median age 1.6 years vs 2 years, p=0.002 from survival analysis). Those with C-terminal deletions occurring later in the region had lower average severity scores than those occurring earlier in the region.

CONCLUSION

In terms of overall severity C-terminal deletion cases would appear to be in the middle of the range. In terms of individual aspects of phenotype growth and ability to ambulate appear to be particular strengths. By pooling data internationally this study has achieved the case numbers to provide a phenotypic profile of C-terminal deletions in Rett syndrome.

Rates and types of hospitalisations for children who have subsequent contact with the child protection system: a population based case-control study

OBJECTIVES

To determine whether children who have child maltreatment allegation or substantiation have a higher rate of general hospital admissions and injury related admissions when compared to other children and to investigate other types of admissions, such as mental health, infections and admissions due to external causes.

STUDY DESIGN

A prospective matched case-control study of children born in Western Australia between 1990 and 2005 using de-identified record linked Child Protection and Hospital Morbidity data. Rates of prior hospital admissions for cases versus controls were calculated, and conditional logistic regression was used to estimate the effect of hospital admission rate on the risk of child maltreatment allegation and substantiated allegation.

RESULTS

Children with child maltreatment allegations and substantiations had higher mean prior admission rates compared to controls. Higher rates of general admissions and admissions for injuries, infections, mental and behavioural disorders, and external causes of morbidity, were associated with a markedly increased risk of child maltreatment allegations and substantiation.

CONCLUSIONS

The hospital system plays not only an important role both in the surveillance of maltreatment-related injuries and conditions but also in the role of prevention in the referral of families who may need support and assistance in ensuring the health and safety of their children. This research highlights the importance of moving to electronic patient records in identifying children who have high rates of admissions and the types of conditions they have previously presented with, particularly for injuries, mental and behavioural disorders and external causes of admissions.

InterRett—The application of bioinformatics to International Rett syndrome research

InterRett, International Rett Syndrome Association (IRSA) Rett Phenotype Database, is a unique international project funded by the IRSA, which brings together child neurologists, geneticists, paediatricians, epidemiologists, researchers and families of affected children. The principal aim of InterRett is to increase the clinical understanding of Rett syndrome throughout the world and with the statistical power of large case numbers, determine any correlations between genotype and the phenotypic characteristics. Since establishment of the database in January 2003, InterRett has registered 286 cases from 24 countries, with family questionnaire data submitted on 242 cases and clinician data on 116 cases. Collated de-identified data gathered from families and clinicians have been incorporated into a searchable online database allowing simple and complex interrogation of the clinical phenotype information. InterRett will also serve as a clearing house for data to encourage inter-country collaboration between researchers and negotiations are in place with several countries for data contributions in excess of 1000 cases. The resulting online database will be an invaluable resource for understanding the nature and management of Rett syndrome, as well as providing a model for other rare childhood disorders.

IDEA (Intellectual Disability Exploring Answers): A population-based database for intellectual disability in Western Australia

Despite the demands it places on individuals, families and the community, intellectual disability (ID) is a neglected area of public health. Accurate estimates of prevalence are sparse and range from 0.5 to 3.0%. The cause of the condition is unknown in at least 50% of cases. This paper describes the Intellectual Disability Exploring Answers (IDEA) database set up in Western Australia to provide an infrastructure for research and to facilitate the planning of service provision for people with ID. Since 1953 a database for ID has been maintained in Western Australia, a state with a population of 1.95 million in an area of 2.52 million km2. The current IDEA database aims to obtain ongoing population-based ascertainment of ID from providers of clinical and educational services, with the potential for linkage to a network of other state databases. The average prevalence of ID for children born in Western Australia over the years 1983-1996 was 15.2 per 1000 live births, with 50% ascertained only through the education system. During this time period 60% of cases were male. Of children with an ID born in Western Australia in 1980-1999 and surviving to 1 year, 30.1% had a birth defect, and the prevalence ratio of birth defects in this group compared to the population with no birth defects was 6.5 (CI 6.3-6.8).

Factors associated with dental admissions for children aged under 5 years in Western Australia

OBJECTIVE

There is limited literature describing dental admissions in preschool children. This paper describes dental hospital admissions and associated factors in children aged under 5 years.

DESIGN

This study uses total population data for Western Australia, which link midwives' information with birth defects, intellectual disability, hospital admissions and deaths. Children born 1980-1995 (n = 383,665) were followed until 5 years. Intellectual disability data were available for children born between 1983 and 1992. Admission data including length of stay were examined.

OUTCOME MEASURES

Admissions for each relevant 9th Revision of the International Classification of Diseases, Clinical Modification (ICD-9) principal diagnosis category and factors associated with having had a dental admission (all categories) and ICD-9 521 (mostly caries) in particular were investigated.

RESULTS

There were 11,523 dental admissions involving 10,493 children. Of all dental admissions, 76% were in ICD-9 category 521, which included admissions for dental caries. After adjusting for confounders, children with intellectual disability (odds ratio 1.92; 95% CI 1.63 to 2.27) and birth defect 1.85 (1.68 to 2.05) were more likely to have had a dental admission. Children living in a region without fluoridated water were also more likely to have had a dental admission 2.16 (1.94 to 2.40). Males were more likely to have had a dental admission 1.16 (1.08 to 1.25), as were children with an indigenous mother 1.17 (1.02 to 1.34). Investigation of ICD-9 521 admissions showed associations similar to those described above except for mother being indigenous, which was associated with reduced likelihood of admission.

CONCLUSION

Given the burden of dental admissions in young children, these findings highlight the need for improved oral care for children.

The common BDNF polymorphism may be a modifier of disease severity in Rett syndrome

BACKGROUND

Rett syndrome (RTT) is caused by mutations in the transcriptional repressor methyl CpG-binding protein 2 (MECP2). Brain-derived neurotrophic factor (BDNF) is a neurotrophic factor playing a major role in neuronal survival, neurogenesis, and plasticity, and it has been shown that BDNF expression is regulated by MeCP2 through a complex interaction. A common polymorphism of BDNF (Val66Met [p.V66M]) has been found to correlate with severity and course of several neuropsychiatric disorders.

METHODS

We examined the association between disease severity score, assessed by the modified Percy score, and BDNF polymorphism, using regression methods, in 125 mutation-positive patients with RTT from the Australian Rett Syndrome Database and an Israeli cohort.

RESULTS

Those who were heterozygous (Val/Met) had slightly more severe disease than those who were homozygous for the wild-type (Val/Val) BDNF polymorphism (increased severity score 2.1, p = 0.09). In those with p.R168X, a commonly occurring MECP2 mutation in RTT, there was a 6-point increase in severity score for those who were heterozygous for the BDNF polymorphism, both unadjusted (p = 0.02) and adjusted for age (p = 0.03). Individuals with the p.R168X mutation and heterozygous for the BDNF polymorphism were also at an increased risk of seizure onset (hazard ratio 5.3, 95% confidence interval 1.6-17.7) compared with those homozygous for the wild-type BDNF allele.

CONCLUSIONS

In addition to mutation type and degree of X-chromosome skewing, the common brain-derived neurotrophic factor (BDNF) polymorphism appears to be another genetic modifier of Rett syndrome (RTT) severity. This suggests that BDNF function may play a significant role in the pathogenesis of RTT.

Rare childhood diseases: how should we respond?

Paradoxically, rare diseases are common, collectively affecting 6-10% of the population and have a huge impact on patients and families, health services, clinicians and the wider community. Accurate data are required to inform clinical practice, government policy and health service planning. We recommend a national approach, similar to that adopted in the USA and Europe, to support research and promote advocacy and equitable access to services for children with rare diseases.

Investigating genotype-phenotype relationships in Rett syndrome using an international data set

BACKGROUND

Rett syndrome is an uncommon neurodevelopmental disorder with an incidence of 1:9,000 live female births. The principal genetic cause was first reported in 1999 when the association with mutations in the methyl-CpG-binding protein 2 (or MECP2) gene was identified. This study uses data from a large international database, InterRett, to examine genotype-phenotype relationships and compares these with previous findings in a population-based cohort.

METHOD

The data set for these analyses was derived from a subset of InterRett cases with subject information collected from the family, the clinician, or both. Individual phenotypic characteristics and clinical severity using three scales were compared among those with eight known recurrent pathogenic MECP2 mutations as well as those with C-terminal deletions (n = 272).

RESULTS

Overall, p.R270X and p.R255X were the most severe and p.R133C and p.R294X were the mildest mutations. Significant differences by mutation were seen for individual phenotypic characteristics such as hand use, ambulation, and language.

CONCLUSIONS

This multicenter investigation into the phenotypic correlates of MECP2 mutations in Rett syndrome has provided a greater depth of understanding than hitherto available about the specific phenotypic characteristics associated with commonly occurring mutations. Although the modifying influence of X inactivation on clinical severity could not be included in the analysis, the findings confirm clear genotype-phenotype relationships in Rett syndrome and show the benefits of collaboration crucial to effective research in rare disorders.

The impact of having a sibling with an intellectual disability: parental perspectives in two disorders

BACKGROUND

The potential effects on other children when there is a child with intellectual disability (ID) in the family are being increasingly recognized. This study describes the impact of having a sibling with Down syndrome or Rett syndrome using a questionnaire completed by parents.

METHODS

The parents of 186 Western Australian children with Down syndrome and 141 Australian girls and women with Rett syndrome participated in the study. Patterns of reporting disadvantages and/or benefits were compared across a number of child and family variables (age, functional ability and birth order of the affected child, number of siblings and number of parents in the family home) and by socio-economic status as measured by the index of relative socio-economic disadvantage and by area of residence. Parents' responses to open-ended questions about the benefits and/or disadvantages for siblings of their child were analysed for themes.

RESULTS

The majority of parents in the Rett syndrome and Down syndrome groups reported both disadvantages and benefits for siblings. In the Rett syndrome group, families from outer regional areas were the least likely to mention disadvantages and those with a smaller family more likely to note disadvantages. In both groups, more socio-economically advantaged families were more likely to report disadvantages. In the Down syndrome group, benefits were also more commonly reported by parents who were socio-economically advantaged, and by larger and two-parent families. Major disadvantages for siblings centred around parental and personal time constraints, relationships and socializing, restrictions, parental emotion and burden of helping. Major benefits were related to personality characteristics.

CONCLUSION

Parents identified both benefits and disadvantages to the siblings of their child with either Rett syndrome or Down syndrome. It is important that these findings are incorporated into any discussion around the impact on the family of a child diagnosed with an ID.

Development of a Video-based Evaluation Tool in Rett Syndrome

This paper describes the development of a video-based evaluation tool for use in Rett syndrome (RTT). Components include a parent-report checklist, and video filming and coding protocols that contain items on eating, drinking, communication, hand function and movements, personal care and mobility. Ninety-seven of the 169 families who initially agreed to participate returned a videotape within 8 months of the first request. Subjects whose videos were returned had a similar age profile to those who did not provide a video but were more likely to have classical than atypical RTT. Evidence of the content and social validity and inter-rater reliability on 11 videos is provided. Video may provide detailed, objective assessment of function and behaviour in RTT.

Early progressive encephalopathy in boys and MECP2 mutations

MECP2 mutations mainly occur in females with Rett syndrome. Mutations have been described in 11 boys with progressive encephalopathy: seven of nine with affected sisters and two de novo. The authors report four de novo occurrences: three pathogenic and one potentially pathogenic. Common features include failure to thrive, respiratory insufficiency, microcephaly, and abnormal motor control. MECP2 mutations should be assessed in boys with progressive encephalopathy and one or more of respiratory insufficiency, abnormal movements or tone, and intractable seizures.

Triple VPI CGS 35601 reduces high blood pressure in low-renin, high-salt Dahl salt-sensitive rats

We previously reported that CGS 35601, a potent triple inhibitor of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme 1, completely normalized mean arterial blood pressure (MABP) in 36-week-old spontaneously hypertensive rats, a normal renin model. The aim of the present study was to determine the effects of this triple vasopeptidase inhibitor (VPI) on the hemodynamic profile of instrumented, conscious, and unrestrained Dahl salt-sensitive (DSS) rats, a gene-prone, high-salt diet-induced low-renin hypertension model. Male DSS rats (mean weight [+/-SEM], 385 +/- 10 g) were fed a normal diet (Group 1) or a high-salt diet (Groups 2 and 3; 8% NaCl in food) for 6 weeks and then instrumented with a carotid catheter and placed individually in metabolic cages for 30 days. The hemodynamic, hematological, and biochemical profiles were assessed daily. Dose-dependent treatment started after a 7-day stabilization period in Groups 1 and 2 (vehicle dosage, 250 microl/hr) and Group 3 (CGS 35601 dosages of 0.1, 1, and 5 mg/kg/day for 6 days per dose by means of constant intra-arterial infusion), followed by a 5-day washout period. Two additional groups included normotensive Wistar rats (Group 4) and DSS rats that received a double high-salt solid (8% NaCl) and liquid (1% NaCl) diet (Group 5). The MABP in rats receiving CGS 35601 decreased in a dose-dependent fashion toward the baseline level observed in DSS rats receiving a normal diet. The heart rate was unaffected. The hemodynamic profile returned to normal during the washout period. This novel triple VPI is a potent and effective antihypertensive agent with a safe short-term profile that may be of interest for treating hypertension and other cardiovascular diseases. Other hypertensive rat models are being tested.

Hospitalisations from birth to 5 years in a population cohort of Western Australian children with intellectual disability

AIMS

To describe the hospitalisation history in the first five years of life for all children born in Western Australia (WA) between 1983 and 1992 and diagnosed with intellectual disability (ID).

METHODS

Unit record linkage of the WA Midwives Collection, WA Intellectual Disability Database, and the WA Hospital Morbidity Dataset provided the population database of WA born children with and without ID. Affected children were divided into those co-affected with autism spectrum disorders (ASD), and those whose ID had or had no known biomedical cause. Those without a biomedical cause were further subdivided into mild-moderate and severe categories.

RESULTS

On average, ID affected children were more likely than non-affected children to be admitted to hospital (RR: 1.64; 95% CI 1.6 to 1.7), on more occasions (5.3 versus 2.2 admissions), for longer (29.6 versus 8.3 days), and for a larger range of clinical diagnoses. The only exception was the group of children co-diagnosed with ASD whose hospitalisation profile resembled more that of non-affected children.

CONCLUSIONS

This total population study is unique because of the availability of the system of linkable population registers and administrative health databases in WA. The results indicated that this vulnerable population of children with ID has substantial medical needs. This paper points to the need for authorities to develop supportive programmes for this population especially in the current climate of de-medicalisation of ID. More research is not only needed on the welfare of the affected children but also on the impact of the substantial medical and other needs of affected children on the rest of their immediate and extended families.

Lost in translation: translational interference from a recurrent mutation in exon 1 of MECP2

BACKGROUND

Rett syndrome (RTT) is an X linked neuro-developmental disorder affecting mostly girls. Mutations in the coding region of MECP2 are found in 80% of classic RTT patients. Until recently, the region encoding MECP2 was believed to comprise exons 2, 3, and 4 with the ATG start site located at the end of exon 2 (MeCP2_e2).

METHODS

Recent reports of another mRNA transcript transcribed from exon 1 (MeCP2_e1) prompted us to screen exon 1 among RNA samples from 20 females with classic or atypical RTT.

RESULTS

A previously reported 11 base pair deletion in exon 1 was detected in one subject with a milder phenotype. Although RNA expression for both protein isoforms was detected from the mutant allele, evaluation of MeCP2 protein in uncultured patient lymphocytes by immunocytochemistry revealed that MeCP2 protein production was restricted to only 74-76% of lymphocytes. X chromosome inactivation studies of genomic DNA revealed similar XCI ratios at the HUMARA locus (73:27 with HpaII and 74:26 with McrBC). We have demonstrated that translation but not transcription of the MeCP2_e2 isoform is ablated by the 11 nucleotide deletion, 103 nucleotides upstream of the e2 translation start site.

CONCLUSIONS

These findings reveal that nucleotides within the deleted sequence in the 5'-UTR of the MeCP2_e2 transcript, while not required for transcription, are essential for translation.

Trisomy 21 and Rett syndrome: a double burden

Rett syndrome is a severe neurodevelopmental disorder generally affecting girls. Affected individuals are apparently normal at birth but later pass through a period of regression with loss of hand and communication skills and the development of hand stereotypies and dyspraxia. Mutations in the methyl-CpG binding protein 2 (MECP2) gene, have now been found to cause Rett syndrome in up to 80% of classical cases. We report a girl with Down syndrome, one of three children with birth defects in a family of five. From the age of 18 months she developed symptomatology considered by her primary physician to be very characteristic of Rett syndrome. However, this remained a clinical diagnosis till the age of 12 years. Laboratory confirmation of the dual diagnosis, which includes a R168X mutation in the MECP2 gene in addition to trisomy 21, has now been possible. The presence of one neurological or developmental disorder does not necessarily preclude a diagnosis of Rett syndrome.