The Cost of Raising Individuals with Fragile X or Chromosome 15 Imprinting Disorders in Australia.

The study characterised differences in costs associated with raising a child between four rare disorders and examined the associations between these costs with clinical severity. Caregivers of 108 individuals with Prader-Willi, Angelman (AS), Chromosome 15q Duplication and fragile X (FXS) syndromes completed a modified Client Services Receipt Inventory and participants completed intellectual/developmental functioning and autism assessments. AS incurred the highest yearly costs per individual ($AUD96,994), while FXS had the lowest costs ($AUD33,221). Intellectual functioning negatively predicted total costs, after controlling for diagnosis. The effect of intellectual functioning on total costs for those with AS was significantly different to the other syndromes. The study highlights the significant costs associated with these syndromes, particularly AS, linked with severity of intellectual functioning.

Progressive resistance training in young people with Prader-Willi syndrome: protocol for a randomised trial (PRESTO).

INTRODUCTION: Preliminary evidence suggests that progressive resistance training may be beneficial for people with Prader-Willi Syndrome (PWS), a rare genetic condition that results in muscle weakness and low muscle tone.To establish whether community-based progressive resistance training is effective in improving the muscle strength of people with PWS; to determine cost-effectiveness; and, to complete a process evaluation assessing intervention fidelity, exploring mechanisms of impact, understanding participant experiences and identifying contextual factors affecting implementation. METHODS AND ANALYSIS: A multisite, randomised controlled trial will be completed. Sixty participants with PWS will be randomised to receive either progressive resistance training (experimental) or non-progressive exercise (placebo control). Participants will be aged 13 to 60 years, be able to follow simple instructions in English and have no contraindications to performing progressive resistance training. The experimental group will complete progressive resistance training two times weekly for 24 weeks supervised by an exercise professional at a community gym. The control group will receive all aspects of the intervention except progressive overload. Outcomes will be assessed at week 25 (primary endpoint) and week 52 by a blinded assessor. The primary outcome is muscle strength assessed using one repetition maximum for upper limb and lower limb. Secondary outcomes are muscle mass, functional strength, physical activity, community participation, health-related quality of life and behaviour. Health economic analysis will evaluate cost-effectiveness. Process evaluation will assess safety and intervention fidelity, investigate mechanism of impact, explore participant experiences and identify contextual factors affecting implementation. Data collection commenced in February 2020 and will conclude in September 2023. ETHICS AND DISSEMINATION: Ethical approval was obtained from The Royal Children's Hospital Human Research Ethics Committee (HREC/50874/RCHM-2019) under the National Mutual Acceptance initiative. Research governance approvals were obtained from five clinical sites. Results will be disseminated through published manuscripts, conference presentations, public seminars and practical resources for stakeholder groups. TRIAL REGISTRATION NUMBER: ACTRN12620000416998; Australian and New Zealand Clinical Trial Registry.

Reducing global health inequalities for a rare disorder: evaluating the international Prader-Willi Syndrome Organisation's Echo® programme.

BACKGROUND: People with rare disorders face significant global health inequalities; the challenge is how to raise awareness and develop a nucleus of experts in a country who are then able to provide guidance to others in that country. The International Prader-Willi Syndrome Organisation (IPWSO) established Project ECHO® with the aim of facilitating the sharing of knowledge and the building of international partnerships to reduce global health inequalities for a particular rare genetically-determined neurodevelopmental disorder, Prader-Willi Syndrome (PWS). Four different ECHO programmes were established for the following groups: (a) Individuals (usually parents) who had taken on a leadership role in their country; (b) health professionals interested in PWS; (c) professional care providers supporting children and adults with PWS; and (d) a Latin American ECHO in Spanish. The programme started in 2020 and an evaluation was undertaken after one year to determine: the extent to which IPWSO had been able to recruit and retain individuals globally; the nature and extent of any benefits gained from the sessions; and examples of how individual involvement in the programme had led to local benefits. The methods included analysing routinely kept process indicators and survey data from the attendees of one component of the programme (the Leadership ECHO), together with a qualitative analysis of survey data and recorded interviews of attendees from countries of differing socio-economic status. RESULTS: We describe the IPWSO ECHO programme and report on the outcomes from the evaluation of one aspect of the programme, the Leadership ECHO. Attendance of the Leadership ECHO sessions was satisfactory, with a mean of 24.7 participants, with participants attending a mean of 5.67 sessions, i.e., 30% of sessions. There was also good global reach, with individuals attending from 34 countries, although there were notable geographic regions with very limited representation. Feedback and interviews demonstrated the positive impact of the programme with some early evidence of positive developments at national level. CONCLUSIONS: Families and professionals from countries with a range of expertise and services offered to people with PWS remained engaged throughout the ECHO programme, established networks of support and fostered the development of good practice.

Body composition and obstructive sleep apnoea assessment in adult patients with Prader-Willi syndrome: a case control study.

INTRODUCTION: In Prader-Willi syndrome (PWS) adult patients, sleep-breathing disorders, especially obstructive sleep apnoea syndrome (OSAS), are very common, whose missed or delayed diagnosis can contribute to further increase cardiovascular morbidity and mortality. PURPOSE: The aim of this cross-sectional study was to evaluate differences in sleep-breathing parameters obtained by overnight cardiorespiratory polygraphy in 13 adult PWS patients and 13 individuals with non-syndromic obesity as controls matched by age, sex, and BMI. METHODS: In all subjects' anthropometric parameters, body composition using bioimpedance analysis and overnight cardiorespiratory monitoring parameters were obtained. RESULTS: Ten (76.9%) PWS patients were diagnosed with OSAS, most notably nine (69.2%) and one PWS (7.7%) with mild and severe OSAS, respectively. Compared with the control group, PWS patients had evidence of higher apnoea-hypopnea index (AHI) (p = 0.04) and oxyhaemoglobin desaturation index (ODI) (p = 0.009). However, no differences were found between the two groups regarding OSAS categories or diagnosis of nocturnal respiratory failure. In the PWS group, there were no significant correlations among AHI, ODI and hypoxemia index (T90) and anthropometric measurements, fat mass (FM), and FM percentage (%). Conversely, in the control group, the sleep-related respiratory indices evaluated correlated positively with BMI, waist circumference, FM and FM%. CONCLUSIONS: This study confirmed that AHI and ODI indices were worse in PWS than in age, sex and BMI-matched controls. The lack of their significant association with the anthropometric parameters and FM supported the existence of PWS-related mechanisms in OSAS pathophysiology that are independent of visceral obesity and FM.

Inter- and intra-observer reliability of the "Assessment of Motor Repertoire- 3 to 5 Months" based on video recordings of infants with Prader-Willi syndrome.

BACKGROUND: The "Assessment of Motor Repertoire-3 to 5 Months", which is a part of Prechtl's General Movements Assessment (GMA), has been gradually applied to infants with genetic metabolic disorders. However, there have been no studies on the application of the GMA for infants with Prader-Willi syndrome (PWS). AIMS: The purpose of this study was to determine the inter- and intra-observer reliability of the assessment tool in a population of infants with PWS. STUDY DESIGN: This was a reliability and agreement study. SUBJECTS: This was a cross-sectional study with15 infants with PWS born at an average gestational age of 38 weeks. OUTCOME MEASURES: Standardized video recordings of 15 infants with PWS (corrected ages of 3 to 5 months) were independently assessed by three observers. Kappa and ICC statistics were applied in inter- and intra- observer reliability analyses. RESULTS: The overall reliability ICC values of the "Motor Optimality Score" (MOS) ranged from 0.84 to 0.98, and the pairwise agreement ranged between 0.86 and 0.95 for inter- observe reliability. In addition, ICC values for the MOS ranged between 0.95 and 0.98 for tester agreement in intra-observer reliability. Complete agreement reliability (100%) was achieved in the subcategories of "Fidgety Movements" and "Movement Character" for the inter- and intra-observer reliability. Moderate to high inter- and intra-observer reliability were found in the subcategories of "Repertoire of Co-Existent Other Movements", "Quality of Other Movements" and "Posture", with kappa values ranging between 0.63 and 1.00. CONCLUSION: There were high levels of inter-and intra-observer agreement in the "Assessment of Motor Repertoire-3 to 5 Months" for infants with PWS. It is possible to carry out standardized quantitative assessments of the motor performance of infants with PWS.

Pediatric growth hormone treatment in Italy: A systematic review of epidemiology, quality of life, treatment adherence, and economic impact.

OBJECTIVES: This systematic review aims to describe 1) the epidemiology of the diseases indicated for treatment with growth hormone (GH) in Italy; 2) the adherence to the GH treatment in Italy and factors associated with non-adherence; 3) the economic impact of GH treatment in Italy; 4) the quality of life of patients treated with GH and their caregivers in Italy. METHODS: Systematic literature searches were performed in PubMed, Embase and Web of Science from January 2010 to March 2021. Literature selection process, data extraction and quality assessment were performed by two independent reviewers. Study protocol has been registered in PROSPERO (CRD42021240455). RESULTS: We included 25 studies in the qualitative synthesis. The estimated prevalence of growth hormone deficiency (GHD) was 1/4,000-10,000 in the general population of children; the prevalence of Short Stature HOmeoboX Containing gene deficiency (SHOX-D) was 1/1,000-2,000 in the general population of children; the birth prevalence of Turner syndrome was 1/2,500; the birth prevalence of Prader-Willi syndrome (PWS) was 1/15,000. Treatment adherence was suboptimal, with a range of non-adherent patients of 10-30%. The main reasons for suboptimal adherence were forgetfulness, being away from home, pain/discomfort caused by the injection. Economic studies reported a total cost for a complete multi-year course of GH treatment of almost 100,000 euros. A study showed that drug wastage can amount up to 15% of consumption, and that in some Italian regions there could be a considerable over- or under-prescribing. In general, patients and caregivers considered the GH treatment acceptable. There was a general satisfaction among patients with regard to social and school life and GH treatment outcomes, while there was a certain level of intolerance to GH treatment among adolescents. Studies on PWS patients and their caregivers showed a lower quality of life compared to the general population, and that social stigma persists. CONCLUSION: Growth failure conditions with approved GH treatment in Italy constitute a significant burden of disease in clinical, social, and economic terms. GH treatment is generally considered acceptable by patients and caregivers. The total cost of the GH treatment is considerable; there are margins for improving efficiency, by increasing adherence, reducing drug wastage and promoting prescriptive appropriateness.

Development and validation of the Pediatric-Youth Hyperphagia Assessment for Prader-Willi syndrome.

OBJECTIVES: Hyperphagia is a highly stressful, life-threatening feature of Prader-Willi syndrome (PWS). It is important to assess this complex behavior accurately over time. This study aimed to develop and validate the Pediatric-Youth Hyperphagia Assessment for Prader-Willi syndrome (PYHAP) as a tool targeting children and adolescents. METHODS: After an extensive literature review and qualitative interviews, the final version of the PYHAP with 14 questions in 3 domains (verbal [5], behavior [4], and social [5]) was developed and tested at Samsung Medical Center in Seoul, Korea from July 2018 to September 2019. Exploratory factor analysis and confirmatory factor analysis (CFA) were performed to confirm construct validity. The correlations between the PYHAP and the Korean Children's Eating Behavior Questionnaire (K-CEBQ) were calculated to evaluate convergent and discriminant validity. Criterion validity and the validity of the response categories were also tested. RESULTS: Cronbach's alpha coefficient of the PYHAP was 0.91. The fit indices for CFA were good (comparative fit index, 0.87; standardized root mean squared residual, 0.08). The domains of the PYHAP were closely correlated with the relevant domains of the K-CEBQ. The accuracy of the PYHAP score for predicting uncontrolled hyperphagia was good (area under the curve, 0.75; 95% confidence interval, 0.65 to 0.85). CONCLUSIONS: The PYHAP was confirmed to be a reliable and valid tool to evaluate hyperphagia in children and adolescents with PWS via caregivers' assessments. It is recommended to use the PYHAP to communicate with parents or caregivers about patients' hyperphagia or to monitor and manage extreme behaviors in children with PWS.

Evaluación orofacial de los niños Síndrome Prader-Willi / Avaliação orofacial de crianças com Síndrome de Prader-Willi / Orofacial assessment of children with Prader-Willi Syndrome

Resumen Objetivo: Evaluar el estado de salud bucal y el crecimiento craneofacial de pacientes con síndrome de Prader-Willi (SPW), en comparación con niños obesos que no padecen SPW. Métodos y resultados: Se seleccionaron 40 niños con SPW y 40 controles obesos de 10,9 años de edad (control: 11,89 años) y un IMC de 22,72 kg / m2 (control de 36,43 kg / m2). La evaluación de la salud oral ha incluído el número de dientes, tipo de dentición, presencia de caries, sangrado gingival, maloclusión, acumulación de placa, erosión dental, hiperplasia gingival e hipoplasia del esmalte. Los cuestionarios evaluaron los hábitos de higiene oral. Las radiografías panorámicas evaluaron el crecimiento craneofacial. El grupo de casos tenía un 6,8% menos de dientes en comparación con el grupo de control. Se observó una diferencia estadísticamente significativa en el sangrado gingival, la erosión dental y la hipoplasia del esmalte (p = 0,009; p = 0,02 y p = 0,006, respectivamente). Aunque no hubo diferencias estadísticamente significativas, se observó un número aumentado de lesiones cariosas y apiñamiento dental en niños con SPW (p = 0,35 y p = 0,07). Ambos grupos mostraron mala higiene dental. Los niños con SPW mostraron un crecimiento de la rama mandibular aumentada en comparación con el control (p = 0.03). Conclusión: Los niños con SPW tenían hemorragia gingival estática aumentada e hipoplasia del esmalte que los controles con obesidad no SPW. Los niños con SPW pueden presentar un crecimiento vertical craneofacial

Objetivo: Avaliar a saúde bucal e o crescimento craniofacial de pacientes pediátricos com SíndromedePrader-Willi(SPW),emcomparação a crianças obesas não-sindrômicas. Métodos e resultados: Foram selecionadas 40 crianças com SPW e 40 controles não obesos com SPW, com idade de 10,9 anos (controle: 11,89 anos) e IMC 22,72 kg / m2 (controle 36,43 kg / m2). Foram avaliados o número de dentes, tipo de dentição, presença de cárie, sangramento gengival, má oclusão, acúmulo de placa bacteriana, erosão dentária, hiperplasia gengival e hipoplasia do esmalte. Os questionários avaliaram os hábitos de higiene bucal. Radiografias panorâmicas avaliaram o crescimento craniofacial. O grupo caso teve um número 6,8% menor de dentes em comparação ao grupo controle. Observouse diferença estatisticamente significante no sangramento gengival, erosão dentária e hipoplasia do esmalte (p = 0,009; p = 0,02 e p = 0,006, respectivamente). Não houve diferença estatisticamente significante, observou-se um número aumentado de lesões de cárie e apinhamento dentário em crianças com SPW (p = 0,35 e p = 0,07). Ambos os grupos apresentaram má higiene dental. As crianças com SPW apresentaram crescimento aumentado do ramo mandibular com diferença estatisticamente significante (p = 0,03). Conclusão: As crianças com SPW apresentaram sangramento gengival estatisticamente aumentado e hipoplasia do esmalte do que os controles não obesos com SPW. Crianças com SPW podem apresentar crescimento vertical craniofacial aumentado. Mais investigações são necessárias para essa população.

Aim: To assess the oral health status and craniofacial growth of patients with Prader-Willi Syndrome (PWS), compared to obese non-PWS children controls. Methods and Result: 40 PWS children and 40 non-PWS obese controls, aged 10.9 years (control: 11.89 years) and BMI 22.72 kg/m2 (control 36.43 kg/m2) were selected. The number of teeth, type of dentition, presence of caries, gingival bleeding, malocclusion, plaque accumulation, dental erosion, gingival hyperplasia, and enamel hypoplasia were assessed. Questionnaires assessed oral hygiene habits. Panoramic radiographs assessed craniofacial growth. The study group had a 6.8% lower number of teeth compared to the control group. A statistically significant difference was seen in gingival bleeding, dental erosion and enamel hypoplasia (p=0,009; p=0,02 and p=0,006; respectively). There were no statistically significant differences, it was observed an augmented number of carious lesions and Although a higher prevalence of carious lesions and dental crowding was observed in PWS children, the difference was not satisctically significant (p=0.35 and p=0.07 respectively). Both groups showed poor dental hygiene. PWS children showed augmented mandibular ramus growth with a statistically significant difference (p=0.03). Conclusion: PWS children had statically augmented gingival bleeding and enamel hypoplasia than non-PWS obese controls. PWS children may present increased craniofacial vertical growth. Further investigations are needed for this population.

Age Distribution, Comorbidities and Risk Factors for Thrombosis in Prader-Willi Syndrome.

: Prader-Willi syndrome (PWS) is an imprinting disorder caused by lack of expression of the paternally inherited 15q11.2-q13 chromosome region. The risk of death from obesity-related complications can worsen with age, but survival trends are improving. Comorbidities and their complications such as thrombosis or blood clots and venous thromboembolism (VTE) are uncommon but reported in PWS. Two phases of analyses were conducted in our study: unadjusted and adjusted frequency with odds ratios and a regression analysis of risk factors. Individuals with PWS or non-PWS controls with exogenous obesity were identified by specific International Classification of Diseases (ICD)-9 diagnostic codes reported on more than one occasion to confirm the diagnosis of PWS or exogenous obesity in available national health claims insurance datasets. The overall average age or average age per age interval (0-17yr, 18-64yr, and 65yr+) and gender distribution in each population were similar in 3136 patients with PWS and 3945 non-PWS controls for comparison purposes, with exogenous obesity identified from two insurance health claims dataset sources (i.e., commercial and Medicare advantage or Medicaid). For example, 65.1% of the 3136 patients with PWS were less than 18 years old (subadults), 33.2% were 18-64 years old (adults), and 1.7% were 65 years or older. After adjusting for comorbidities that were identified with diagnostic codes, we found that commercially insured PWS individuals across all age cohorts were 2.55 times more likely to experience pulmonary embolism (PE) or deep vein thrombosis (DVT) than for obese controls (p-value: 0.013; confidence interval (CI) :1.22-5.32). Medi caid-insured individuals across all age cohorts with PWS were 0.85 times more likely to experience PE or DVT than obese controls (p-value: 0.60; CI: 0.46-1.56), with no indicated age difference. Age and gender were statistically significant predictors of VTEs, and they were independent of insurance coverage. There was an increase in occurrence of thrombotic events across all age cohorts within the PWS patient population when compared with their obese counterparts, regardless of insurance type.

A profile of mental health and behaviour in Prader-Willi syndrome.

BACKGROUND: Prader-Willi syndrome (PWS) is a neurogenetic syndrome with an associated behavioural phenotype and a high incidence of behaviours of concern and psychiatric co-morbidity. These associated behaviours and co-morbidities are not well addressed by existing interventions, and they impact significantly on affected individuals and their caregivers. METHODS: We undertook a national survey of the needs of individuals with PWS and their families in Ireland. In this paper, we report on the parent/caregiver-reported mental health, behavioural and access to services. RESULTS: Over 50% of individuals with PWS in this survey had at least one reported psychiatric diagnosis, the most common diagnosis was anxiety. The most commonly reported behaviours in children were skin picking, repetitive questioning, difficulty transitioning and non-compliance. The same four behaviours were reported by caregivers as being the most commonly occurring in adolescents and adults in addition to food-seeking behaviours. Increased needs for mental health services were also reported by caregivers. Individuals with PWS had an average wait of 22 months for an appointment with a psychologist and 4 months for an appointment with a psychiatrist. CONCLUSION: This study highlighted high levels of psychiatric co-morbidities and behavioural concerns in individuals with PWS in Ireland. The findings of this study suggest that there is an urgent need to provide specialist psychiatric and behavioural interventions to manage complex mental health and behavioural needs to better support individuals with PWS and reduce caregiver burden.

Edição genômica como estudo da regulação da expressão do hormônio de crescimento na síndrome de Prader-Willi / Genomic editing as a study of the regulation of growth hormone expression in Prader-Willi syndrome

A síndrome de Prader-Willi (SPW) é associada a distúrbios neurológicos, comportamentais e diversas deficiências hormonais, incluindo o hormônio do crescimento (GH). Embora o tratamento de reposição do GH melhore a composição corporal, o crescimento e o quadro clínico geral, esta não é uma cura e suas bases clínicas ainda são desconhecidas na síndrome. A SPW ocorre por três mecanismos moleculares: deleção paterna da região 15q11-q13; dissomia uniparental materna 15; ou defeitos de imprinting. A linhagem celular GH3 de pituitária de rato foi utilizada por ser um modelo bem estudado de células secretoras de GH e prolactina. Utilizando o sistema CRISPR-Cas9, realizamos a deleção completa da região ortóloga da SPW de 3,2 Mb na linhagem GH3, produzindo o genótipo da síndrome in vitro, para investigar quais segmentos gênicos da SPW estão envolvidos na regulação do GH. A investigação de off-targets por sequenciamento Sanger revelou desde reparos sem alteração nucleotídica até grandes rearranjos nos flancos dos sítios-alvo dos gRNAs, inclusive com inserções não previstas de DNA exógeno. Nossos dados ressaltam a necessidade de projetar cuidadosamente as condições experimentais e caracterizar minuciosamente os materiais genéticos obtidos pelo sistema CRISPR-Cas9. A análise do DNA no flanco proximal da região da SPW em ratos demonstrou sequências que podem representar o marco inicial do silenciamento gênico por imprinting na região, assim como ocorre próximo a UBE3A em humanos na porção distal da região ortóloga. Os quatro modelos de sublinhagens SPW-Knockout gerados neste trabalho com deleções de 3,2 Mb envolvendo toda a região da SPW permitirão compreender melhor a relação entre os genes da síndrome e as vias moleculares envolvidas na regulação do GH, além da sua utilização como modelos em novos estudos sobre a SPW. O gene SNORD107 surgiu como o principal candidato a regular o GH dentro da região da SPW, podendo formar um complexo ribonucleoprotéico que exerceria função regulatória pós-transcricional na cadeia de produção do GH.

Prader-Willi syndrome (PWS) is associated with neurodevelopmental and behavioral abnormalities and numerous hormonal deficiencies, including growth hormone (GH). Although GH replacement treatment improves body composition, growth, and the overall clinical presentation, it is not a cure and its clinical basis is still unknown in the syndrome. PWS occurs by three molecular mechanisms: paternal deletion of the 15q11-q13 region; maternal uniparental disomy 15; or imprinting defects. The rat pituitary GH3 cell line is a well-studied model of GH and prolactin-secreting cells. Using the CRISPR-Cas9 system, we performed the complete deletion of the 3.2 Mb PWS orthologous region in GH3 cells, generating the syndrome genotype in vitro to investigate which PWS genes are involved in GH regulation. Off-target analysis by Sanger sequencing revealed perfect breakpoint repairs, but also large rearrangements on the flanking sites of the gRNA targets, including unexpected insertions of exogenous DNA. These data highlight the need to carefully design the experimental conditions and fully characterize the genetic materials obtained by CRISPR-Cas9. DNA analysis on the proximal flank of the PWS region in rats has shown sequences that can mark the initial borders of genomic imprinting, as it occurs close to UBE3A in humans in the distal portion of the orthologous region. The four PWS-Knockout models generated in this work with 3.2 Mb deletions involving the entire PWS region will allow a better understanding of the relationship between PWS genes and the molecular pathways involved in GH regulation and can be used as models in new PWS studies. The SNORD107 gene has emerged as the main candidate to regulate GH within the PWS region and may form a ribonucleoprotein complex with a post-transcriptional regulatory function in the GH production pathway.

Complex Economic Behavior Patterns Are Constructed from Finite, Genetically Controlled Modules of Behavior.

Complex ethological behaviors could be constructed from finite modules that are reproducible functional units of behavior. Here, we test this idea for foraging and develop methods to dissect rich behavior patterns in mice. We uncover discrete modules of foraging behavior reproducible across different strains and ages, as well as nonmodular behavioral sequences. Modules differ in terms of form, expression frequency, and expression timing and are expressed in a probabilistically determined order. Modules shape economic patterns of feeding, exposure, activity, and perseveration responses. The modular architecture of foraging changes developmentally, and different developmental, genetic, and parental effects are found to shape the expression of specific modules. Dissecting modules from complex patterns is powerful for phenotype analysis. We discover that both parental alleles of the imprinted Prader-Willi syndrome gene Magel2 are functional in mice but regulate different modules. Our study found that complex economic patterns are built from finite, genetically controlled modules.

Analysis of the Prader-Willi syndrome imprinting center using droplet digital PCR and next-generation whole-exome sequencing.

BACKGROUND: Detailed analysis of imprinting center (IC) defects in individuals with Prader-Willi syndrome (PWS) is not readily available beyond chromosomal microarray (MA) analysis, and such testing is important for a more accurate diagnosis and recurrence risks. This is the first feasibility study of newly developed droplet digital polymerase chain reaction (ddPCR) examining DNA copy number differences in the PWS IC region of those with IC defects. METHODS: The study cohort included 17 individuals without 15q11-q13 deletions or maternal disomy but with IC defects as determined by genotype analysis showing biparental inheritance. Seven sets of parents and two healthy, unrelated controls were also analyzed. RESULTS: Copy number differences were distinguished by comparing the number of positive droplets detected by IC probes to those from a chromosome 15 reference probe, GABRß3. The ddPCR findings were compared to results from other methods including MA, and whole-exome sequencing (WES) with 100% concordance. The study also estimated the frequency of IC microdeletions and identified gene variants by WES that may impact phenotypes including CPT2 and NTRK1 genes. CONCLUSION: Droplet digital polymerase chain reaction is a cost-effective method that can be used to confirm the presence of microdeletions in PWS with impact on genetic counseling and recurrence risks for families.

Assessment of fat-free mass from bioelectrical impedance analysis in men and women with Prader-Willi syndrome: cross-sectional study.

We have recently shown that population-specific formulae are required to estimate fat-free mass (FFM) from bioelectrical impedance analysis (BIA) in obese women with Prader-Willi syndrome (PWS) matched by age and percent fat mass (FM) to non-PWS women. The present cross-sectional study was aimed at developing generalised BIA equations that could be used in PWS subjects independently of sex and FM. We used dual-energy X-ray absorptiometry to measure FFM and BIA to measure whole-body impedance at 50 kHz (Z50) in 34 women and 21 men with PWS. The impedance index, that is, height (cm)2/Z50 (Ω), explained 77% (BCa-bootstrapped 95% CI 65 to 85%) of the variance of FFM with a root mean squared error of the estimate of 3.7 kg (BCa-bootstrapped 95% CI 3.2 to 4.5 kg). BIA can be used to estimate FFM in obese and non-obese PWS men and women by means of population-specific equations.

Dynamic balance assessment during gait in children with Down and Prader-Willi syndromes using inertial sensors.

Down (DS) and Prader-Willi (PWS) syndromes are chromosomal disorders both characterized by obesity, ligament laxity, and hypotonia, the latter associated with gait instability. Although these shared features may justify a common rehabilitation approach, evidence exists that adults with DS and PWS adopt different postural and walking strategies. The development of an instrumented protocol able to describe these strategies and quantify patients' gait stability in the current clinical routine would be of great benefit for health professionals, allowing them to design personalized rehabilitation programs. This is particularly true for children with DS and PWS, where motor development is dramatically constrained by severe hypotonia and muscle weakness. The aim of this study was, thus, to propose an instrumented protocol, integrated with the clinical routine and based on the use of wearable inertial sensors, to assess gait stability in DS and PWS children. Fifteen children with DS, 11 children with PWS, and 12 typically developing children (CG) were involved in the study. Participants performed a 10-meter walking test while wearing four inertial sensors located at pelvis, sternum, and both distal tibiae levels. Spatiotemporal parameters (walking speed, stride frequency, and stride length) and a set of indices related to gait symmetry and upper-body stability (Root Mean Square, Attenuation Coefficient and Improved Harmonic Ratio) were estimated from pelvis and sternum accelerations. The Gross Motor Functional Measures (GMFM-88) and Intelligence Quotient (IQ Wechsler) were also assessed for each patient. A correlation analysis among the GMFM-88 and IQ scales and the estimated parameters was then performed. Children with DS and PWS exhibit reduced gait symmetry and higher accelerations at pelvis level than CG. While these accelerations are attenuated by about 40% at sternum level in CG and DS, PWS children display significant smaller attenuations, thus reporting reduced gait stability, most likely due to their typical "Trendelenburg gait". Significant correlations were found between the estimated parameters and the GMFM-88 scale when considering the whole PWS and DS group and the PWS group alone. These results promote the adoption of wearable technology in clinical routines to monitor gait patterns in children with DS and PWS: the proposed protocol allows to markedly characterize patient-specific motor limitations even when clinical assessment scores provide similar results in terms of pathology severity. This protocol could be adopted to support health professionals in designing personalized treatments that, in turn, could help improving patients' quality of life in terms of both physical and social perspectives.

Assessment of Safety and Outcome of Lateral Hypothalamic Deep Brain Stimulation for Obesity in a Small Series of Patients With Prader-Willi Syndrome.

Importance: Deep brain stimulation (DBS) has been investigated for treatment of morbid obesity with variable results. Patients with Prader-Willi syndrome (PWS) present with obesity that is often difficult to treat. Objective: To test the safety and study the outcome of DBS in patients with PWS. Design, Setting, and Participants: This case series was conducted in the Hospital das Clínicas, University of São Paulo, Brazil. Four patients with genetically confirmed PWS presenting with severe obesity were included. Exposure: Deep brain stimulation electrodes were bilaterally implanted in the lateral hypothalamic area. After DBS implantation, the treatment included the following phases: titration (1-2 months), stimulation off (2 months), low-frequency DBS (40 Hz; 1 month), washout (15 days), high-frequency DBS (130 Hz; 1 month), and long-term follow-up (6 months). Main Outcomes and Measures: Primary outcome measures were adverse events recorded during stimulation and long-term DBS treatment. Secondary outcomes consisted of changes in anthropometric measures (weight, body mass index [calculated as weight in kilograms divided by height in meters squared], and abdominal and neck circumference), bioimpedanciometry, and calorimetry after 6 months of treatment compared with baseline. The following evaluations and measurements were conducted before and after DBS: clinical, neurological, psychiatric, neuropsychological, anthropometry, calorimetry, blood workup, hormonal levels, and sleep studies. Adverse effects were monitored during all follow-up visits. Results: Four patients with PWS were included (2 male and 2 female; ages 18-28 years). Baseline mean (SD) body mass index was 39.6 (11.1). Two patients had previous bariatric surgery, and all presented with psychiatric comorbidity, which was well controlled with the use of medications. At 6 months after long-term DBS, patients had a mean 9.6% increase in weight, 5.8% increase in body mass index, 8.4% increase in abdominal circumference, 4.2% increase in neck circumference, 5.3% increase in the percentage of body fat, and 0% change in calorimetry compared with baseline. Also unchanged were hormonal levels and results of blood workup, sleep studies, and neuropsychological evaluations. Two patients developed stimulation-induced manic symptoms. Discontinuation of DBS controlled this symptom in 1 patient. The other required adjustments in medication dosage. Two infections were documented, 1 associated with skin picking. Conclusions and Relevance: Safety of lateral hypothalamic area stimulation was in the range of that demonstrated in patients with similar psychiatric conditions receiving DBS. In the small cohort of patients with PWS treated in our study, DBS was largely ineffective.

Intercambiabilidad entre biosimilares de la hormona de crecimiento / Interchangeability between biosimilars of growth hormone

CONTEXTO CLÍNICO: La hormona del crecimiento (HC), también denominada somatotrofina o somatropina, es un polipéptido natural producido por la glándula hipofisaria bajo el control del hipotálamo. Es una hormona esencial para el crecimiento en niños y también tiene importantes efectos en el metabolismo de proteínas, lípidos y carbohidratos. En los niños, la HC promueve el crecimiento, estimulando la secreción de hormonas (somatomedinas) en el hígado. En los adultos, la HC tiene efectos anabólicos estimulando la síntesis de proteínas en el músculo y la secreción de ácidos grasos del tejido adiposo. Inhibe la captación de glucosa por el músculo y estimula la captación de aminoácidos. TECNOLOGÍA: La hormona de crecimiento recombinante (rhGH, del inglés Recombinant human growth hormone), es una hormona proteica no glicosilada de 191 aminoácidos estabilizado por medio de dos puentes disulfuro y con un peso molecular de aproximadamente 22.000 daltons. La dosis de rhGH recomendada se difiere según el diagnóstico y tamaño del. Se administra en forma subcutánea 6-7 veces por semana.1,2 Los efectos adversos son raros y pueden incluir cefaleas, náuseas y vómitos, problemas visuales, artralgias, mialgias, parestesias, hipotiroidismo y reacciones locales en el sitio de inyección. OBJETIVO: Evaluar la evidencia disponible acerca de la eficacia, seguridad y aspectos relacionados de la intercambiabilidad entre biosimilares de hormona de crecimiento. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas (incluyendo Medline, Cochrane y CRD), en buscadores genéricos de Internet, agencias de evaluación de tecnologías sanitarias y financiadores de salud. Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias y económicas, guías de práctica clínica y políticas de cobertura de otros sistemas de salud cuando estaban disponibles. RESULTADOS: Para el siguiente informe se incluyeron un ECA, dos estudios antes-después no controlados y dos recomendaciones o consensos de expertos. Los tres estudios incluídos evaluaron la eficacia y seguridad del intercambio entre Genotropinâ (la cual fue considerada siempre marca de referencia) y Omnitropeâ (siempre considerado el biosimilar). No se encontraron estudios clínicos de intercambiabilidad con las otras marcas comerciales disponibles en Argentina. CONCLUSIONES: Actualmente en Argentina se encuentran disponibles ocho especialidades medicinales que contienen hormona de crecimiento recombinante. Según las autorizaciones de la Agencia Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT) estas marcas comerciales contienen la misma droga, y están aprobadas para las mismas indicaciones. En esta revisión rápida de la literatura se encontró evidencia de moderada calidad donde se comparan dos de las especialidades medicinales disponibles actualmente, se observo que el reemplazo de Genotropin por Omnitrope no alteraría la altura final, los valores de desviación estándar de la misma y la velocidad de crecimiento (expresada en cm/año).

Hypothalamus Specific Re-Introduction of SNORD116 into Otherwise Snord116 Deficient Mice Increased Energy Expenditure.

The Snord116 gene cluster has been recognised as a critical contributor to the Prader-Willi syndrome (PWS), with mice lacking Snord116 displaying many classical PWS phenotypes, including low postnatal body weight, reduced bone mass and increased food intake. However, these mice do not develop obesity as a result of increased energy expenditure. To understand the physiological function of SNORD116 better and potentially rescue the altered metabolism of Snord116-/- mice, we used an adeno-associated viral (AAV) approach to reintroduce the product of the Snord116 gene into the hypothalamus in Snord116-/- mice at different ages. The results obtained show that mid-hypothalamic re-introduction of SNORD116 in 6-week-old Snord116-/- mice leads to significantly reduced body weight and weight gain, which is associated with elevated energy expenditure. Importantly, when the intervention targets other areas such as the anterior region of the hypothalamus or the reintroduction occurs in older mice, the positive effects on energy expenditure are diminished. These data indicate that the metabolic symptoms of PWS develop gradually and the Snord116 gene plays a critical role during this process. Furthermore, when we investigated the consequences of SNORD116 re-introduction under conditions of thermoneutrality where the mild cold stress influences are avoided, we also observed a significant increase in energy expenditure. In conclusion, the rescue of mid-hypothalamic Snord116 deficiency in young Snord116 germline deletion mice increases energy expenditure, providing fundamental information contributing to potential virus-mediated genetic therapy in PWS.

Somatropina para o tratamento da síndrome de Prader-Willi / Somatropin for the treatment of Prader-Willi syndrome

CONTEXTO: A síndrome de Prader-Willi (SPW) é uma doença genética, caracterizada pela ausência de genes expressos paternalmente na região cromossômica 15q11-13 devido a deleção, dissomia materna, defeito de impressão ou translocação cromossômica. TECNOLOGIA: Somatropina. PERGUNTA: Somatropina é eficaz e segura para o tratamento da Síndrome de Prader-Willi? EVIDÊNCIAS: Foram incluídos dois estudos que avaliaram o tratamento com somatropina. Em indivíduos adultos com Síndrome de Prader-Willi, a terapia com hormônio de crescimento durante 12 meses levou a diminuição da massa corporal gorda, visceral e adiposidade subcutânea e o aumento da massa corporal magra. Alterações semelhantes na massa corporal gorda e massa corporal magra foram encontradas em estudos mais longos. Houve um pequeno aumento na glicemia de jejum e uma tendência para o aumento da insulina em jejum e resistência à insulina. O evento adverso mais comum relatado foi edema. Outros eventos adversos além das alterações na homeostase da glicose, foram mialgias e cefaleia. Outro estudo relata que quatro ensaios clínicos randomizados demonstraram que o uso de hormônio do crescimento melhorou o desenvolvimento mental e motor dos lactentes, aumentando a sua força física, muscular e sua linguagem e dois ensaios clínicos randomizados demonstraram melhora da funcionalidade física e da força da parede torácica em crianças. Os estudos de séries de casos demonstraram que o uso de hormônio do crescimento pode melhorar a função motora de lactentes, crianças e adultos com Síndrome de Prader-Willi. Uma combinação de tratamento com hormônio do crescimento e treinamento físico pode ser apropriada para melhorar o desenvolvimento motor, especialmente em lactentes. CONCLUSÕES: Tratamento com hormônio de crescimento diminuiu a massa gorda corporal, aumentou a massa magra e melhorou a função motora em adultos. Também melhorou o desenvolvimento mental e motor dos lactentes, além de aumentar a funcionalidade física e a força da parede torácica em crianças.

The High Direct Medical Costs of Prader-Willi Syndrome.

OBJECTIVE: To assess medical resource utilization associated with Prader-Willi syndrome (PWS) in the US, hypothesized to be greater relative to a matched control group without PWS. STUDY DESIGN: We used a retrospective case-matched control design and longitudinal US administrative claims data (MarketScan) during a 5-year enrollment period (2009-2014). Patients with PWS were identified by Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code 759.81. Controls were matched on age, sex, and payer type. Outcomes included total, outpatient, inpatient and prescription costs. RESULTS: After matching and application of inclusion/exclusion criteria, we identified 2030 patients with PWS (1161 commercial, 38 Medicare supplemental, and 831 Medicaid). Commercially insured patients with PWS (median age 10 years) had 8.8-times greater total annual direct medical costs than their counterparts without PWS (median age 10 years: median costs $14 907 vs $819; P < .0001; mean costs: $28 712 vs $3246). Outpatient care comprised the largest portion of medical resource utilization for enrollees with and without PWS (median $5605 vs $675; P < .0001; mean $11 032 vs $1804), followed by mean annual inpatient and medication costs, which were $10 879 vs $1015 (P < .001) and $6801 vs $428 (P < .001), respectively. Total annual direct medical costs were ∼42% greater for Medicaid-insured patients with PWS than their commercially insured counterparts, an increase partly explained by claims for Medicaid Waiver day and residential habilitation. CONCLUSION: Direct medical resource utilization was considerably greater among patients with PWS than members without the condition. This study provides a first step toward quantifying the financial burden of PWS posed to individuals, families, and society.