Experience of gastrostomy using a quality care framework: the example of rett syndrome

Normalized Clinical Severity Scores Reveal a Correlation between X Chromosome Inactivation and Disease Severity in Rett Syndrome

Rett Syndrome (RTT) is a severe neurodevelopmental disorder predominately diagnosed in females and primarily caused by pathogenic variants in the X-linked gene Methyl-CpG Binding Protein 2 (MECP2). Most often, the disease causing the MECP2 allele resides on the paternal X chromosome while a healthy copy is maintained on the maternal X chromosome with inactivation (XCI), resulting in mosaic expression of one allele in each cell. Preferential inactivation of the paternal X chromosome is theorized to result in reduced disease severity; however, establishing such a correlation is complicated by known MECP2 genotype effects and an age-dependent increase in severity. To mitigate these confounding factors, we developed an age- and genotype-normalized measure of RTT severity by modeling longitudinal data collected in the US Rett Syndrome Natural History Study. This model accurately reflected individual increase in severity with age and preserved group-level genotype specific differences in severity, allowing for the creation of a normalized clinical severity score. Applying this normalized score to a RTT XCI dataset revealed that XCI influence on disease severity depends on MECP2 genotype with a correlation between XCI and severity observed only in individuals with MECP2 variants associated with increased clinical severity. This normalized measure of RTT severity provides the opportunity for future discovery of additional factors contributing to disease severity that may be masked by age and genotype effects.

Growth patterns in individuals with CDKL5 deficiency disorder

AIM

To compare growth in individuals with cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder with population norms and to investigate the effect of gastrostomy on growth.

METHOD

The longitudinal study included 353 individuals from the International CDKL5 Disorder Database with any anthropometric measurement in baseline and/or follow-up questionnaires. The British 1990 growth reference was used to determine the age- and sex-standardized z-score. Repeated cross-sectional data were fitted using a Gaussian linear regression model with generalized estimating equations.

RESULTS

All growth parameters were below the general population norm (mean z-scores: weight -0.97, height -0.65, body mass index [BMI] -0.81, head circumference -2.12). The disparity was particularly pronounced for all anthropometric measurements after 4 years of age except for BMI. Moreover, individuals with gastrostomy placement were shown to have a larger decrease than those without.

INTERPRETATION

In addition to weight, height, and BMI, head circumference was also compromised in this disorder. Microcephaly could be considered a helpful diagnostic feature, especially in adults. Any benefit of gastrostomy on weight and BMI was mainly seen in the early years.

Patient experience or patient satisfaction? A systematic review of child- and family-reported experience measures in pediatric surgery

PURPOSE

Patient-reported outcome measures (PROMs) and patient-reported experience measures (PREMs) are increasingly recognized as important health care quality indicators. PREMs measure patients' perception of the care they have received, differing from satisfaction ratings, which measure their expectations. The use of PREMs in pediatric surgery is limited, prompting this systematic review to assess their characteristics and identify areas for improvement.

METHODS

A search was conducted in eight databases from inception until January 12, 2022, to identify PREMs used with pediatric surgical patients, with no language restrictions. We focused on studies of patient experience but also included studies that assessed satisfaction and sampled experience domains. The quality of the included studies was appraised using the Mixed Methods Appraisal Tool.

RESULTS

Following title and abstract screening of 2633 studies, 51 were included for full-text review, of which 22 were subsequently excluded because they measured only patient satisfaction rather than experience, and 14 were excluded for a range of other reasons. Out of the 15 included studies, questionnaires used in 12 studies were proxy-reported by parents and in 3 by both parents and children; none focused only on the child. Most instruments were developed in-house for each specific study, without patients' involvement in the process, and were not validated.

CONCLUSIONS

Although PROMs are increasingly used in pediatric surgery, PREMs are not yet in use, being typically substituted by satisfaction surveys. Significant efforts are needed to develop and implement PREMs in pediatric surgical care, in order to effectively capture children's and families' voices.

LEVEL OF EVIDENCE

IV.

Improving clinical trial readiness to accelerate development of new therapeutics for Rett syndrome

Rett syndrome is associated with severe functional impairments and many comorbidities, each in urgent need of treatments. Mutations in the MECP2 gene were identified as causing Rett syndrome in 1999. Over the past 20 years there has been an abundance of preclinical research with some studies leading to human clinical trials. Despite this, few viable therapeutic options have emerged from this investment of effort. Reasons for this lack of success as they relate both to preclinical research and the clinical trial landscape are discussed. Considering what needs to be done to promote further success in the field, we take a positive and constructive approach and introduce the concept of clinical trial readiness and its necessary ingredients for Rett syndrome. These include: listening to the needs of families; support from advocacy groups; optimising use of existing clinic infrastructures and available natural history data; and, finally, the validation of existing outcome measures and/or the development and validation of new measures. We conclude by reiterating the need for a collaborative and coordinated approach amongst the many different stakeholder groups and the need to engage in new types of trial design which could be much more efficient, less costly and much less burdensome on families.

Psychosocial support for families of children with neurodisability who have or are considering a gastrostomy: the G-PATH mixed-methods study

Background

Evidence reviews recommend consistent and structured support for children with neurodisability and their caregivers in care pathways in which professionals recommend a gastrostomy feeding tube. To date, and to our knowledge, no research has shown how these recommendations have been implemented.

Objectives

The objectives were to describe different exemplar models of psychosocial support and provide an estimate of their resources and costs.

Design

This was a mixed-methods study involving (1) a web-based survey, (2) a qualitative, collective case study of psychosocial support provision in four services and (3) an estimate of costs and preference through a willingness-to-pay study.

Setting

Four service configurations in different locations in England and Scotland.

Participants

Participants were staff who responded to a survey (n = 67) and interviewees (staff, n = 58; parents/children, n = 29).

Findings

Psychosocial support was rarely formalised or documented; it was delivered by different members of the multidisciplinary team, rather than by designated staff, and it was often integrated into appointments dominated by clinical care. Parents expressed different needs for support but reported little opportunity to discuss emotional aspects. Psychologists were not routinely involved and, in general, families were underserved by psychosocial services. Professionals constructed families’ need for psychosocial support in terms of their own roles and the management of risk. Mechanisms for integrating and delivering support were identified, including models of care that linked community and tertiary health services and integrated health and education through pooled budgets. Although generally valued by both staff and parents, peer-to-peer parent support was not consistently offered. Barriers included concerns about confidentiality and appropriately matching parents. Parents participated as members of a feeding committee at one site. Three analytical constructs described the provision of psychosocial support: ‘hidden work’, expressing emotional vulnerability and negotiations around risks and values. The cost-of-support study found that there was a mean of 2.25 appointments (n = 8 parents or carers) over the previous 12 months. The cost of health-care professionals’ time spent on providing psychosocial support ranged from £0.00 to £317.37 per child per year, with an average cost of £76.42, at 2017 prices. In the willingness-to-pay study the median rank of enhanced support, involving the opportunity to see a psychologist and parental peers, was significantly higher than that of usual care (n = 96 respondents, both carers and professionals, who completed rating of the service; p < 0.001).

Limitations

It proved difficult to disseminate a national survey, which resulted in a small number of returns, and to cost the provision of psychosocial support, which we designated as ‘hidden work’, owing to the lack of recording in clinical systems. Moreover, estimates were based on small numbers.

Conclusions

Parent interviews and the willingness-to-pay study demonstrated a preference for enhanced psychosocial support. The study suggests that there is a need for services to formally assess families’ needs for psychosocial support to ensure that provision is planned, costed and made explicit in care pathways. Personalised interventions may assist with the targeting of resources and ensuring that there is an appropriate balance in focus on both clinical care and psychosocial support needs in relation to and following treatment.

Future work

More work is needed to develop tools to assess families’ needs for psychosocial support and the effectiveness of training packages to strengthen team competency in providing support.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 8, No. 38. See the NIHR Journals Library website for further project information.

Gastrostomy and quality of life in children with intellectual disability: a qualitative study

OBJECTIVE

Children with intellectual disability and marked feeding difficulties may undergo gastrostomy insertion to assist with their nutritional and medication needs. Use has increased recently for younger children, and it is intended to provide long-term support. This study explored the perceived value of gastrostomy for the quality of life (QOL) of children with intellectual disabilities and their families.

METHODS

Twenty-one primary caregivers of children with intellectual disability aged 2-18 years participated in semistructured telephone interviews. Data were analysed using directed content analysis, and data were coded to existing QOL domains relevant to children with intellectual disability and their families.

RESULTS

Benefits in each of the child and family QOL domains were represented in the interview data. For children, the impacts of gastrostomy for the physical health domain were predominant, supplemented by experiences of value for emotional well-being, social interactions, leisure activities and independence. For families, gastrostomy was integrated into multiple aspects of QOL relating to family interactions, parenting, resources and supports, health and safety, and advocacy support for disability. Shortcomings related to difficulties with equipment and complications.

CONCLUSIONS

Our comprehensive overview of the value of gastrostomy for children with intellectual disability and their families was classified within a QOL framework. Gastrostomy was mainly supportive over long time periods across many QOL domains. Findings will be of use to patient counselling and education and the development of family support resources.

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.

Risk of Hospitalizations Following Gastrostomy in Children with Intellectual Disability

OBJECTIVE

To examine the frequency of hospital admissions before and after gastrostomy insertion in children with severe intellectual disability.

STUDY DESIGN

We conducted a retrospective cohort study using linked health administrative and disability data from Western Australia (WA) and New South Wales (NSW). Children born between 1983 and 2009 in WA and 2002 and 2010 in NSW who had a gastrostomy insertion performed (n = 673 [WA, n = 325; NSW, n = 348]) by the end of 2014 (WA) and 2015 (NSW) were included. Conditional Poisson regression models were used to evaluate the age-adjusted effect of gastrostomy insertion on acute hospitalizations for all-cause, acute lower respiratory tract infections (LRTI), and epilepsy admissions.

RESULTS

The incidence of all-cause hospitalizations declined at 5 years after procedure (WA cohort 1983-2009: incidence rate ratio, 0.70 [95% CI, 0.60-0.80]; WA and NSW cohort 2002-2010: incidence rate ratio, 0.63 [95% CI, 0.45-0.86]). Admissions for acute LRTI increased in the WA cohort and remained similar in the combined cohort. Admissions for epilepsy decreased 4 years after gastrostomy in the WA cohort and were generally lower in the combined cohort. Fundoplication seemed to decrease the relative incidence of acute LRTI admissions in the combined cohort.

CONCLUSIONS

Gastrostomy was associated with health benefits including reduced all-cause and epilepsy hospitalizations, but was not protective against acute LRTI. These decreases in hospitalizations may reflect improved delivery of nutrition and medications.

Longitudinal effects of caregiving on parental well-being: the example of Rett syndrome, a severe neurological disorder

Little longitudinal research has examined parental well-being in those with a child with specific genetic developmental disorder although the associated severe neurological impairments and multiple physical comorbidities likely place substantial burden of caregiving on the parent. We aimed to examine longitudinally the well-being of parents of individuals included in the Australian Rett Syndrome Database over the period from 2002 to 2011 using the Short Form 12 Health Survey. Residential remoteness, the child being a teenager at baseline, having frequent sleep disturbances or behavioural problems, and the type of MECP2 gene mutation were each associated with later poorer parental physical well-being scores. Being a single parent or on a low income was also associated with later poorer physical well-being, while the child having enteral feeding was associated with later poorer emotional well-being. Both the physical and emotional well-being of the parent improved if the child was living in out-of-home care. Our findings suggest that some opportunities do exist for clinicians to help optimise parental well-being. Being alert to the possibility and need for management of a child's sleep or emotional disturbance is important as is awareness of the additional likely parental burden as the child moves through adolescence into early adulthood and their need for additional support at that time. However, the findings also highlight the complex nature of parental well-being over time in parents of children with a severe neurological disorder and how they may be affected by a range of inter-related family and child factors.

Development of a web-based assessment tool that evaluates the meal situation when a child has a percutaneous endoscopic gastrostomy

BACKGROUND

Children with cancer often suffer side effects from their treatment, for example nausea and vomiting, which can lead to malnutrition. If a child cannot eat orally, a percutaneous endoscopic gastrostomy (PEG) can improve his or her well-being, psychosocial development and growth by enabling the supply of nourishment and facilitating the administration of necessary medicines. Few data exist on children's comfort when using a PEG. The aim of this study was firstly to develop three versions of a web-based assessment tool in which children, families, and healthcare professionals would be able to register their observations and assessments for evaluating the meal situation when a child has a PEG and secondly to validate the content of the tool.

METHODS

A qualitative design was chosen with purposive sampling of participants. Five children with cancer, five parents, five registered nurses and five paediatricians participated first in an interview and then in a member check of the web-based tool. The data were analysed with manifest qualitative content analysis.

RESULTS

The results highlighted four categories of issues which needed to be revised in the web-based tool: words which were difficult for the participants to understand, items which contained several questions, items which needed to be split into more items to be answerable and the layout of the questionnaire. The web-based tool was revised according to the categories, and then a member check evaluated and finally confirmed the revisions.

CONCLUSIONS

A web-based tool may be able to evaluate the meal situation when a child with cancer has a PEG. The tool may be able to detect early failures of the PEG, facilitating early action from the healthcare professionals in supporting the child and his or her parents in their care of the PEG. In the long run, this web-based tool may also be able to increase the quality of care of children living with a PEG.

Epidemiology of gastrostomy insertion for children and adolescents with intellectual disability

The largest group of recipients of pediatric gastrostomy have neurological impairment with intellectual disability (ID). This study investigated trends in first gastrostomy insertion according to markers of disadvantage and ID etiology. Linked administrative and health data collected over a 32-year study period (1983-2014) for children with ID born between 1983 and 2009 in Western Australia were examined. The annual incidence rate change over calendar year was calculated for all children and according to socioeconomic status, geographical remoteness, and Aboriginality. The most likely causes of ID were identified using available diagnosis codes in the linked data set. Of 11,729 children with ID, 325 (2.8%) received a first gastrostomy within the study period. The incidence rate was highest in the 0-2 age group and there was an increasing incidence trend with calendar time for each age group under 6 years of age. This rate change was greatest in children from the lowest socioeconomic status quintile, who lived in regional/remote areas or who were Aboriginal. The two largest identified groups of ID were genetically caused syndromes (15.1%) and neonatal encephalopathy (14.8%).Conclusion: Gastrostomy is increasingly used in multiple neurological conditions associated with ID, with no apparent accessibility barriers in terms of socioeconomic status, remoteness, or Aboriginality. What is Known: • The use of gastrostomy insertion in pediatrics is increasing and the most common recipients during childhood have neurological impairment, most of whom also have intellectual disability (ID). What is New: • Nearly 3% of children with ID had gastrostomy insertion performed, with the highest incidence in children under 3 years of age. • Gastrostomy use across different social groups was equitable in the Australian setting.

Impact of Gastrostomy Placement on Nutritional Status, Physical Health, and Parental Well-Being of Females with Rett Syndrome: A Longitudinal Study of an Australian Population

OBJECTIVES

To evaluate how age-related trends in nutritional status, physical health, and parental well-being in females with Rett syndrome may be related to gastrostomy placement and to examine the impact of the procedure on mortality.

STUDY DESIGN

We included 323 females from the Australian Rett Syndrome Study and analyzed their demographic, genetic, and child and parental health data collected from over 6 waves of follow-up questionnaire between 2000 and 2011. We used mixed-effects models to estimate the association between repeated measures of outcomes and age, gastrostomy placement and their interaction and Cox proportional hazards regression models to estimate relative risks of mortality for individuals with gastrostomy.

RESULTS

Nearly one-third (30.3%) of the cases underwent gastrostomy placement. Nutritional status based on weight, height, and body mass index (BMI) improved over time, and BMI was greater in individuals with gastrostomy placement than in those without (adjusted β = 0.87, 95% CI 0.02-1.73). There was no association between gastrostomy placement and individual's physical health outcomes or parental physical and mental health, nor did the age trend of these outcomes vary by gastrostomy insertion status. Nevertheless, among those at risk of suboptimal weight, the all-cause mortality rate was greater in those who had gastrostomy placement compared with those who had not (hazard ratio 4.07, 95% CI 1.96-8.45).

CONCLUSION

Gastrostomy placement was associated with improvement in BMI in females with Rett syndrome, but its long-term impact on individuals and their families is unclear.

Respiratory morbidity in Rett syndrome: an observational study

AIM

Respiratory illness is a major cause of morbidity and mortality in Rett syndrome. This study investigated respiratory morbidity and relationships with age, mutation type, feeding, and walking status.

METHOD

Families registered with the InterRett database (n=399) provided data on the health of their child with Rett syndrome (age 2-57y). Hospital admissions because of lower respiratory tract infection (LRTI) over a 5-year exposure period were investigated by age, mutation type, enteral feeding, and walking status.

RESULTS

A hospital admission for LRTI over the previous 5 years was reported for slightly more than one-fifth (21.4%) of individuals. Age and mutation groups did not seem to influence hospital admissions for LRTI but there was nearly twice the risk of an admission with enteral feeding (adjusted relative risk 1.79, 95% confidence interval [CI] 1.21-2.65). Compared with independent walking, being unable to walk was associated with a sixfold increased risk (adjusted relative risk 6.73, 95% CI 3.42-13.25), with assisted walking associated with an intermediate risk.

INTERPRETATION

Beyond the influence of mutation type, walking seems to have protective effects on respiratory health. Further studies of exercise physiology in Rett syndrome and how this can be influenced by increasing activity levels are indicated.

WHAT THIS PAPER ADDS

Rett syndrome is associated with increased vulnerability to lower respiratory tract infection (LRTI) requiring hospitalization. Enteral feeding is associated with a higher risk of hospital admission for LRTI. Assisted walking mitigates the risk of hospital admission for LRTI for those unable to walk independently.

Enteral Tube Feeding in Paediatric Mitochondrial Diseases

We investigated the effects of enteral tube feeding in Korean children with mitochondrial diseases. We performed a retrospective chart review of 68 paediatric patients with mitochondrial diseases on enteral tube feeding at a tertiary referral centre. The outcome of enteral nutrition was evaluated by decrease in gastrointestinal (GI) symptoms, weight gain, and increase in developmental quotient (DQ) among patients with data available. Among 68 patients, 56 (82%) were on gastrostomy and 12 (18%) were on prolonged nasogastric (NG) tube feeding. Decrease of GI symptoms was present in 37 of 48 patients (77%). Weight gain was present in 18 of 64 patients (28%) and was more prominent in the gastrostomy group (n = 17/54, 32%). Increase in DQ was similar between the NG tube and gastrostomy groups (total n = 10/48, 21%). Complications occurred in 42% (n = 5/12) of the NG tube group and 64% (n = 36/56) of the gastrostomy group. They varied in range, from mild to severe. Most complications were minor; there were 5 cases (9%) requiring gastrostomy removal or additional procedure and 2 cases (4%) of gastrostomy-related morbidity. Our results show that in paediatric patients with mitochondrial diseases, enteral tube feeding could help enhance quality of life by relieving GI symptoms, ameliorate growth failure and enhance development.

Autonomic breathing abnormalities in Rett syndrome: caregiver perspectives in an international database study

BACKGROUND

Rett syndrome is a severe neurodevelopmental disorder associated with mutations in the MECP2 gene. Irregular breathing patterns and abdominal bloating are prominent but poorly understood features. Our aims were to characterize the abnormal breathing patterns and abdominal bloating, investigate the distribution of these by age and mutation type and examine their impact and management from a caregiver perspective.

METHODS

We invited previously recruited families from the International Rett Syndrome Study to complete a web-based questionnaire concerning their family member with Rett syndrome aged between 2 and 57 years. We used logistic regression to investigate presence, frequency and impact of breath-holding, hyperventilation, or abdominal bloating by age group and mutation type. Age of onset for both breathing abnormalities was investigated using time-to-onset analysis, and the Kaplan-Meier method was used to estimate the failure function for the study sample. Descriptive statistics were used to characterize the management of irregular breathing.

RESULTS

Questionnaires were returned by 413/482 (85.7%) families. Breath-holding was reported for 68.8%, hyperventilation for 46.4% and abdominal bloating for 42.4%. Hyperventilation was more prevalent and frequent in those younger than 7 years of age and abdominal bloating in those aged over 20 years. Onset of breathing irregularities usually occurred during early childhood. Caregivers perceived that daily life was considerably impacted for almost half (44.1%) of those with abdominal bloating and in just over than a third of those with breath-holding (35.8%) or hyperventilation (35.1%). Although perceived impact was broadly comparable between age and mutation groups for breath-holding, hyperventilation and abdominal bloating, girls and women with a p.Arg294* mutation were considered to be more affected by all three conditions. Only 31 individuals had received medically prescribed treatments including 12 different medications, added oxygen, rebreathing apparatus or non-invasive ventilation.

CONCLUSIONS

Autonomic disturbances are prevalent and burdensome in Rett syndrome. This information may guide the design of inclusion criteria and outcome measures for clinical intervention trials targeting autonomic abnormalities. Further investigation of available treatments is necessary to delineate evidence-based management pathways.

Impacts of caring for a child with the CDKL5 disorder on parental wellbeing and family quality of life

Background

Although research in this area remains sparse, raising a child with some genetic disorders has been shown to adversely impact maternal health and family quality of life. The aim of this study was to investigate such impacts in families with a child with the CDKL5 disorder, a newly recognised genetic disorder causing severe neurodevelopmental impairments and refractory epilepsy.

Methods

Data were sourced from the International CDKL5 Disorder Database to which 192 families with a child with a pathogenic CDKL5 mutation had provided data by January 2016. The Short Form 12 Health Survey Version 2, yielding a Physical Component Summary and a Mental Component Summary score, was used to measure primary caregiver’s wellbeing. The Beach Center Family Quality of Life Scale was used to measure family quality of life. Linear regression analyses were used to investigate relationships between child and family factors and the various subscale scores.

Results

The median (range) age of the primary caregivers was 37.0 (24.6–63.7) years and of the children was 5.2 (0.2–34.1) years. The mean (SD) physical and mental component scores were 53.7 (8.6) and 41.9 (11.6), respectively. In mothers aged 25–54 years the mean mental but not the physical component score was lower than population norms. After covariate adjustment, caregivers with a tube-fed child had lower mean physical but higher mean mental component scores than those whose child fed orally (coefficient = −4.80 and 6.79; p = 0.009 and 0.012, respectively). Child sleep disturbances and financial hardship were negatively associated with the mental component score. The mean (SD) Beach Center Family Quality of Life score was 4.06 (0.66) and those who had used respite services had lower scores than those who had not across the subscales.

Conclusions

Emotional wellbeing was considerably impaired in this caregiver population, and was particularly associated with increased severity of child sleep problems and family financial difficulties. Family quality of life was generally rated lowest in those using respite care extensively, suggesting that these families may be more burdened by daily caregiving.

Clinical and biological progress over 50 years in Rett syndrome

In the 50 years since Andreas Rett first described the syndrome that came to bear his name, and is now known to be caused by a mutation in the methyl-CpG-binding protein 2 (MECP2) gene, a compelling blend of astute clinical observations and clinical and laboratory research has substantially enhanced our understanding of this rare disorder. Here, we document the contributions of the early pioneers in Rett syndrome (RTT) research, and describe the evolution of knowledge in terms of diagnostic criteria, clinical variation, and the interplay with other Rett-related disorders. We provide a synthesis of what is known about the neurobiology of MeCP2, considering the lessons learned from both cell and animal models, and how they might inform future clinical trials. With a focus on the core criteria, we examine the relationships between genotype and clinical severity. We review current knowledge about the many comorbidities that occur in RTT, and how genotype may modify their presentation. We also acknowledge the important drivers that are accelerating this research programme, including the roles of research infrastructure, international collaboration and advocacy groups. Finally, we highlight the major milestones since 1966, and what they mean for the day-to-day lives of individuals with RTT and their families.

How can clinical ethics guide the management of comorbidities in the child with Rett syndrome?

Rett syndrome is a rare disorder caused by a mutation in the MECP2 gene. Those affected generally have severe functional impairments, and medical comorbidities such as scoliosis and poor growth are common. There is a paucity of information on the natural history of many rare disorders and an even greater deficit of evidence to guide best practice. The population-based and longitudinal Australian Rett Syndrome Database established in 1993 has supported investigations of the natural history of Rett syndrome and effectiveness of treatments. This paper reviews the disorder Rett syndrome and evidence for the management of scoliosis and poor growth within a clinical ethics framework. Compared with conservative management, we have shown that spinal fusion is associated with reduced mortality and better respiratory health. We have also shown that gastrostomy insertion is associated with subsequent weight gain. Family counselling for both procedures necessarily must include family perspectives and careful clinical attention to their needs and wishes. Vignettes describing family decision-making and experiences are presented to illustrate the principals of beneficence and autonomy in determining the best interests of the child and family. A blend of evidence-based practice with a strong clinical ethics framework has capacity to build existing strengths in families and reduce the negative impacts of disability and in so doing, optimise the health and wellbeing of those with Rett syndrome.

A Core Outcome Set for Children With Feeding Tubes and Neurologic Impairment: A Systematic Review

CONTEXT

Uncertainty exists about the impacts of feeding tubes on neurologically impaired children. Core outcome sets (COS) standardize outcome selection, definition, measurement, and reporting.

OBJECTIVE

To synthesize an evidence base of qualitative data on all outcomes selected and/or reported for neurologically impaired children 0 to 18 years living with gastrostomy/gastrojejunostomy tubes.

DATA SOURCES

Medline, Embase, and Cochrane Register databases searched from inception to March 2014.

STUDY SELECTION

Articles examining health outcomes of neurologically impaired children living with feeding tubes.

DATA EXTRACTION

Outcomes were extracted and assigned to modified Outcome Measures in Rheumatology 2.0 Filter core areas; death, life impact, resource use, pathophysiological manifestations, growth and development.

RESULTS

We identified 120 unique outcomes with substantial heterogeneity in definition, measurement, and frequency of selection and/or reporting: "pathophysiological manifestation" outcomes (n = 83) in 79% of articles; "growth and development" outcomes (n = 13) in 55% of articles; "death" outcomes (n = 3) and "life impact" outcomes (n = 17) in 39% and 37% of articles, respectively; "resource use" outcomes (n = 4) in 14%. Weight (50%), gastroesophageal reflux (35%), and site infection (25%) were the most frequently reported outcomes.

LIMITATIONS

We were unable to investigate effect size of outcomes because quantitative data were not collected.

CONCLUSIONS

The paucity of outcomes assessed for life impact, resource use and death hinders meaningful evidence synthesis. A COS could help overcome the current wide heterogeneity in selection and definition. These results will form the basis of a consensus process to produce a final COS.

Caretaker Quality of Life in Rett Syndrome: Disorder Features and Psychological Predictors

OBJECTIVE

Rett syndrome is a severe neurodevelopmental disorder affecting approximately one in 10,000 female births. The clinical features of Rett syndrome are known to impact both patients' and caretakers' quality of life in Rett syndrome. We hypothesized that more severe clinical features would negatively impact caretaker physical quality of life but would positively impact caretaker mental quality of life.

METHODS

Participants were individuals enrolled in the Rett Natural History Study with a diagnosis of classic Rett syndrome. Demographic data, clinical disease features, caretaker quality of life, and measures of family function were assessed during clinic visits. The Optum SF-36v2 Health Survey was used to assess caretaker physical and mental quality of life (higher scores indicate better quality of life). Descriptive, univariate, and multivariate analyses were used to characterize relationships between child and caretaker characteristics and caretaker quality of life.

RESULTS

Caretaker physical component scores (PCS) were higher than mental component scores (MCS): 52.8 (9.7) vs 44.5 (12.1). No differences were demonstrated between the baseline and 5-year follow-up. In univariate analyses, disease severity was associated with poorer PCS (P = 0.006) and improved MCS (P = 0.003). Feeding problems were associated with poorer PCS (P = 0.007) and poorer MCS (P = 0.018). In multivariate analyses, limitations in caretaker personal time and home conflict adversely affected PCS. Feeding problems adversely impacted MCS.

CONCLUSIONS

Caretaker quality of life in Rett syndrome is similar to that for caretakers in other chronic diseases. Disease characteristics significantly impact quality of life, and feeding difficulties may represent an important clinical target for improving both child and caretaker quality of life. The stability of quality-of-life scores between baseline and five years adds important value.

Deficiency of GABAergic synaptic inhibition in the Kölliker-Fuse area underlies respiratory dysrhythmia in a mouse model of Rett syndrome

KEY POINTS

Life threatening breathing irregularity and central apnoeas are highly prevalent in children suffering from Rett syndrome. Abnormalities in inhibitory synaptic transmission have been associated with the physiopathology of this syndrome, and may underlie the respiratory disorder. In a mouse model of Rett syndrome, GABAergic terminal projections are markedly reduced in the Kölliker-Fuse nucleus (KF) in the dorsolateral pons, an important centre for control of respiratory rhythm regularity. Administration of a drug that augments endogenous GABA localized to this region of the pons reduced the incidence of apnoea and the respiratory irregularity of Rett female mice. Conversely, the respiratory disorder was recapitulated by blocking GABAergic transmission in the KF area of healthy rats. This study helps us understand the mechanism for generation of respiratory abnormality in Rett syndrome, pinpoints a brain site responsible and provides a clear anatomical target for the development of a translatable drug treatment. Central apnoeas and respiratory irregularity are a common feature in Rett syndrome (RTT), a neurodevelopmental disorder most often caused by mutations in the methyl-CpG-binding protein 2 gene (MECP2). We used a MECP2 deficient mouse model of RTT as a strategy to obtain insights into the neurobiology of the disease and into mechanisms essential for respiratory rhythmicity during normal breathing. Previously, we showed that, systemic administration of a GABA reuptake blocker in MECP2 deficient mice markedly reduced the occurrence of central apnoeas. Further, we found that, during central apnoeas, post-inspiratory drive (adductor motor) to the upper airways was enhanced in amplitude and duration in Mecp2 heterozygous female mice. Since the pontine Kölliker-Fuse area (KF) drives post-inspiration, suppresses inspiration, and can reset the respiratory oscillator phase, we hypothesized that synaptic inhibition in this area is essential for respiratory rhythm regularity. In this study, we found that: (i) Mecp2 heterozygous mice showed deficiency of GABA perisomatic bouton-like puncta and processes in the KF nucleus; (ii) blockade of GABA reuptake in the KF of RTT mice reduced breathing irregularity; (iii) conversely, blockade of GABAA receptors in the KF of healthy rats mimicked the RTT respiratory phenotype of recurrent central apnoeas and prolonged post-inspiratory activity. Our results show that reductions in synaptic inhibition within the KF induce rhythm irregularity whereas boosting GABA transmission reduces respiratory arrhythmia in a murine model of RTT. Our data suggest that manipulation of synaptic inhibition in KF may be a clinically important strategy for alleviating the life threatening respiratory disorders in RTT.