Medical, psychological and social features in a large cohort of adults with Prader-Willi syndrome: experience from a dedicated centre in France

Exploring the Diagnostic Complexity of Diabetes Subtypes in Pediatric Obesity: A Case Report of an Adolescent With Prader-Willi Phenotype and Literature Review

Obesity among adolescents poses a significant global health concern with profound short- and long-term impact on physical and mental well-being. The intricate relationship between obesity and the onset of diabetes remains ambiguous, particularly in cases where the manifestation may differ from that observed in individuals with uncomplicated obesity. Herein, we present the case of a 14-year-old male adolescent with Prader-Willi phenotype and subsequent obesity, exhibiting symptoms of polyuria and polydipsia over a 10-day period, indicative of potential diabetes mellitus (DM). Laboratory assessments revealed a hemoglobin A1c level of 10%, confirming the suspected diagnosis. Notably, despite the absence of ketosis, elevated C-peptide levels and the presence of slightly positive islet-cell antibodies warranted further investigation. While the presence of antibodies typically aligns with a diagnosis of type 1 DM, recent research has highlighted the occurrence of anti-insulin pancreatic cell antibodies in type 2 DM cases. This article aims to delve into the multifaceted issues surrounding adolescent obesity, atypical presentations of DM with positive antibodies, and the long-term management of patients with genetic syndromes.

A pilot rating system to evaluate the quality of goal attainment scales used as outcome measures in rehabilitation

Goal Attainment Scaling (GAS) is a method for writing person-centred approach evaluation scales that can be used as an outcome measure in clinical or research settings in rehabilitation. To be used in a research setting, it requires a high methodological quality approach. The aim of this study was to explore the feasibility and reliability of the GAS quality rating system, to ensure that GAS scales used as outcome measures are valid and reliable. Secondary objectives were: (1) to compare goal attainment scores' reliability according to how many GAS levels are described in the scale; and (2) to explore if GAS scorings are influenced by who scores goal attainment. The GAS scales analysed here were set collaboratively by 57 cognitively impaired adults clients and their occupational therapist. Goals had to be achieved within an inpatient one-month stay, during which clients participated in an intervention aimed at improving planning skills in daily life. The GAS quality rating system proved to be feasible and reliable. Regarding GAS scores, interrater reliability was higher when only three of the five GAS levels were described, i.e., "three milestone GAS" (0.74-0.92), than when all five levels were described (0.5-0.88), especially when scored by the clients (0.5 -0.88).

Prader-Willi syndrome in a large sample from Spain: general features, obesity and regular use of psychotropic medication

BACKGROUND

Prader-Willi syndrome (PWS), a genetically determined disorder, the most frequent cause of early onset obesity, is associated with physical and cognitive dysfunctions and behavioural disturbances; these disturbances are frequently treated with psychotropic medication. The aim of this cross-sectional study was to describe the characteristics of the first large national sample of persons with PWS in Spain and analyse the relationships of those characteristics with key demographic and clinical factors, particularly with obesity and the regular use of psychotropic medication.

METHODS

Participants were recruited among all members of the Spanish Prader-Willi Association who agreed to take part in the study and fulfilled its inclusion criteria. Family and patient demographic features, family size and birth order, intelligence quotient (IQ), anthropometric measures, lifestyle habits, behavioural disturbances (with the Aberrant Behavior Checklist) and clinical data, as well as use of psychotropic drugs and their side effects (with the UKU scale), were collected in genetically confirmed cases of PWS. Bivariate and logistic regression analyses were used for determining the associations of demographic and clinical factors with both obesity and the regular use of psychotropic medication.

RESULTS

The cohort included 177 participants (aged 6-48 years), that is, 90 (50.8%) males and 87 (49.2%) females. Behavioural disturbances were present in a range of 75% to 93% of participants; psychotropic medication was prescribed to 81 (45.8%) of them. Number of siblings showed a direct correlation with IQ, especially among males, and inappropriate speech was more intense in only-child females. Obesity was, in parallel, strongly associated with ascending age and with not being currently under growth hormone (GH) treatment. Participants taking any psychotropic medication were characterised by more frequent age ≥30 years, high level of hyperactivity and a psychiatric diagnosis.

CONCLUSIONS

Characterisation of persons with PWS in Spain confirms their physical and behavioural phenotype and supports the long-term application of GH therapy and the rational use of psychotropic medication.

Endocrine features of Prader-Willi syndrome: a narrative review focusing on genotype-phenotype correlation

Prader-Willi syndrome (PWS) is a complex genetic disorder caused by three different types of molecular genetic abnormalities. The most common defect is a deletion on the paternal 15q11-q13 chromosome, which is seen in about 60% of individuals. The next most common abnormality is maternal disomy 15, found in around 35% of cases, and a defect in the imprinting center that controls the activity of certain genes on chromosome 15, seen in 1-3% of cases. Individuals with PWS typically experience issues with the hypothalamic-pituitary axis, leading to excessive hunger (hyperphagia), severe obesity, various endocrine disorders, and intellectual disability. Differences in physical and behavioral characteristics between patients with PWS due to deletion versus those with maternal disomy are discussed in literature. Patients with maternal disomy tend to have more frequent neurodevelopmental problems, such as autistic traits and behavioral issues, and generally have higher IQ levels compared to those with deletion of the critical PWS region. This has led us to review the pertinent literature to investigate the possibility of establishing connections between the genetic abnormalities and the endocrine disorders experienced by PWS patients, in order to develop more targeted diagnostic and treatment protocols. In this review, we will review the current state of clinical studies focusing on endocrine disorders in individuals with PWS patients, with a specific focus on the various genetic causes. We will look at topics such as neonatal anthropometry, thyroid issues, adrenal problems, hypogonadism, bone metabolism abnormalities, metabolic syndrome resulting from severe obesity caused by hyperphagia, deficiencies in the GH/IGF-1 axis, and the corresponding responses to treatment.

What endocrinologists can do to prevent cardiovascular complications in adults with Prader-Willi syndrome: Lessons from a case series

CONTEXT

Prader-Willi syndrome (PWS) is a complex rare genetic syndrome. Mortality in patients with PWS is 3% per year. In nearly half of the patients, the cause of death is of cardiopulmonary origin. Prevention, diagnosis and treatment of cardiovascular (CV) disease in PWS adults is complicated by the behavioral phenotype, reduced ability to express physical complaints, high pain threshold and obesity.

OBJECTIVE

To describe the challenges in prevention, diagnosis and treatment of CV disease in PWS adults, in order to increase awareness and improve medical care.

METHODS

Retrospective study of medical records of adults visiting the Dutch PWS reference center.

RESULTS

We describe the challenges encountered during diagnosis and treatment of four PWS adults with heart failure. All had pre-existent peripheral edema. CV risk factors in these patients were obesity (n=4), type 2 diabetes mellitus (n=2), hypertension (n=2), hypogonadism (n=3) and sleep apnea (n=2). Remarkably, all patients were younger than 40 years during their first cardiac decompensation. All patients presented with progressive shortness of breath and/or orthopnea and progressive pitting edema. In 117 controls with PWS without CV problems, 31% had leg edema.

CONCLUSION

Diagnosing CV problems in PWS adults is challenging. Peripheral edema is common in PWS adults without CV morbidity, which makes edema in general a poor marker for heart failure. However, when edema is of the pitting kind and progressive, this is a strong predictor of cardiac decompensation. We provide practical recommendations for diagnosing and treating CV problems in this vulnerable patient population.

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.

Bone Health in Adults With Prader-Willi Syndrome: Clinical Recommendations Based on a Multicenter Cohort Study

CONTEXT

Prader-Willi syndrome (PWS) is a rare complex genetic syndrome, characterized by delayed psychomotor development, hypotonia, and hyperphagia. Hormone deficiencies such as hypogonadism, hypothyroidism, and growth hormone deficiency are common. The combination of hypotonia, low physical activity, and hypogonadism might lead to a decrease in bone mass and increase in fracture risk. Moreover, one would expect an increased risk of scoliosis due to hypotonia and low physical activity.

OBJECTIVE

To study the prevalence and risk factors for skeletal problems (reduced bone mineral density, fractures, and scoliosis) in adults with PWS.

METHODS

We retrospectively collected patient characteristics, medical history, medication, biochemical measurements, dual-energy X-ray absorptiometry scans, and spinal X-rays and reviewed the current literature.

RESULTS

We included 354 adults with PWS (median age 31 years; 43% males), of whom 51 (14%) had osteoporosis (T-score below -2.5) and 143 (54%) had osteopenia (T-score -1 to -2.5). The most prevalent modifiable risk factors for osteoporosis were hypogonadism, insufficient dairy intake, sedentary lifestyle, and corticosteroid use. Male sex was associated with osteoporosis (P = .005). Growth hormone treatment was not associated with osteoporosis. A history of vertebral fractures was present in 10 (3%) and nonvertebral fractures in 59 (17%). Scoliosis was present in 263 (80%), but no modifiable risk factors were identified.

CONCLUSION

Besides scoliosis, osteoporosis is common in adults with PWS. Based on the literature and the risk factors for osteoporosis found in our cohort, we provide practical clinical recommendations to avoid skeletal complications in these vulnerable patients.

Health Problems in Adults with Prader-Willi Syndrome of Different Genetic Subtypes: Cohort Study, Meta-Analysis and Review of the Literature

Prader−Willi syndrome (PWS) is a complex, rare genetic disorder caused by a loss of expression of paternally expressed genes on chromosome 15q11.2-q13. The most common underlying genotypes are paternal deletion (DEL) and maternal uniparental disomy (mUPD). DELs can be subdivided into type 1 (DEL-1) and (smaller) type 2 deletions (DEL-2). Most research has focused on behavioral, cognitive and psychological differences between the different genotypes. However, little is known about physical health problems in relation to genetic subtypes. In this cross-sectional study, we compare physical health problems and other clinical features among adults with PWS caused by DEL (N = 65, 12 DEL-1, 27 DEL-2) and mUPD (N = 65). A meta-analysis, including our own data, showed that BMI was 2.79 kg/m2 higher in adults with a DEL (p = 0.001). There were no significant differences between DEL-1 and DEL-2. Scoliosis was more prevalent among adults with a DEL (80% vs. 58%; p = 0.04). Psychotic episodes were more prevalent among adults with an mUPD (44% vs. 9%; p < 0.001). In conclusion, there were no significant differences in physical health outcomes between the genetic subtypes, apart from scoliosis and BMI. The differences in health problems, therefore, mainly apply to the psychological domain.

Endocrine and Metabolic Illnesses in Young Adults with Prader-Willi Syndrome

Prader−Willi syndrome (PWS) is a rare genetic disorder characterized by an insatiable appetite that leads to morbid obesity. Previous studies reported health problems in adults with PWS. However, studies on younger adults are lacking, and there are no specific studies of endocrine and metabolic illness in this age group. We performed a retrospective cohort study of 68 individuals with PWS aged 19 to 34 years at Samsung Medical Center. The prevalence of endocrine and metabolic illnesses were compared with those in an age-, sex-, and BMI-matched healthy control group. Young adults with PWS had a higher prevalence of metabolic syndrome (35.3% vs. 4.4%), type 2 diabetes mellitus (50.0% vs. 5.4%), hypertension (30.8% vs. 16.1%), dyslipidemia (38.2% vs. 14.7%), decreased bone density (26.4% vs. 0.9%), and sleep apnea (32.3% vs. 4.4%) than controls (all p < 0.05). The PWS group that maintained recombinant human growth (rhGH) treatment in adulthood had a lower probability of having a BMI ≥ 30 at the last follow-up (odds ratio = 0.106 (0.012−0.948), p = 0.045). Endocrine and metabolic illnesses in individuals with PWS may have already started in the early teens; therefore, appropriate screening and early intervention are important. Better understanding of the natural history of PWS and age-related complications will lead to better-quality medical care for individuals with PWS.

High Prevalence of Scoliosis in a Large Cohort of Patients with Prader-Willi Syndrome

The characteristics of scoliosis were investigated in a large cohort of children and adults with Prader–Willi syndrome (PWS), analysing the role of age, gender, puberty, body mass index (BMI), genotype and growth hormone therapy (GHT) on its onset and severity. A retrospective cross-sectional study was performed in 180 patients with genetically confirmed PWS (96 females), aged 17.6 ± 12 years. Eighty-five subjects (47%) were obese. One hundred and fifty subjects (83.3%) were on GHT, while 30 patients had never been treated. Overall, 150 subjects (83.3%) were affected by scoliosis, 80.2% of children and adolescents and 87.8% of adults. A mild degree of scoliosis was observed in 58 patients (38.7%), moderate in 43 (28.7%) and severe in 49 (32.6%). Median age at diagnosis of scoliosis was 6.3 years, while the severe forms were diagnosed earlier (median age: 3.8 years). The cumulative probability at 5 years of age was equal to 0.403 and almost doubled at 15 years. No significant associations were found between scoliosis and genotype, gender, pubertal stage, GHT and BMI. A corset was prescribed to 75 subjects (50%) at a median age of 7.5 years, while 26 subjects (17.3%) underwent surgery at a median age of 13.1 years. Our data indicate that scoliosis is one of the major concerns for PWS patients that increases with age, and therefore suggest the need for regular systematic monitoring of spinal deformity from paediatric age.

Psychiatric behavioral effect and characteristics of type 2 diabetes mellitus on Japanese patients with Prader-Willi syndrome: a preliminary retrospective study

OBJECTIVES

In recent years, research on behavioral and psychiatric problems of adults with Prader-Willi syndrome (PWS) has gained attention. However, no report is available regarding the relationship between psychiatric illness and type 2 diabetes mellitus (T2DM) in patients with PWS. Therefore, we evaluated a behavioral assessment to address the lack of data on the association between psychiatric behavior and T2DM.

METHODS

This was a retrospective single-center study of patients with PWS. Patients with PWS whose blood tests were performed in our hospital between January 2018 and December 2019 and aged >10 years were included. We evaluated the data, including the behavioral patterns of Japanese PWS patients with T2DM.

RESULTS

Overall, 114 patients were evaluated; 33 patients (28.9%) developed T2DM. The age of T2DM onset was 18.0 years (interquartile range [IQR], 14.6-21.4 years). The median body mass index at T2DM onset was 33.7 kg/m² (IQR, 30.0-37.4 kg/m²). Between-group comparisons of the intelligence quotient, Food-Related Problem Questionnaire (FRPQ), and Japanese versions of the Short Sensory Profile and Aberrant Behavior Checklist showed a significant difference only in FRPQ scores (p=0.003).

CONCLUSIONS

The occurrence of T2DM among Japanese patients with PWS remains high. Only the FRPQ was significantly different between the T2DM and the non-T2DM group.

Diabetes Mellitus in Prader-Willi Syndrome: Natural History during the Transition from Childhood to Adulthood in a Cohort of 39 Patients

Type 2 diabetes mellitus (T2DM) affects 20% of patients with Prader-Willi syndrome (PWS), with many cases diagnosed during the transition period. Our aim was to describe the natural history of T2DM in patients with PWS before the age of 25 years and to develop screening and preventive strategies. Thirty-nine patients followed in the French PWS Reference Center were included (median age 25.6 years [23.7; 31.7]). Twenty-one had been treated with growth hormone (GH), fifteen had not, and three had an unknown status. The median age at T2DM diagnosis was 16.8 years (11–24) and the median BMI was 39 kg/m² [34.6; 45], with 34/35 patients living with obesity. The patients displayed frequent psychiatric (48.3% hospitalization,) and metabolic (56.4% hypertriglyceridemia,) comorbidities and a parental history of T2DM (35.7%) or overweight (53.6%) compared to the PWS general population. There was no difference in BMI and metabolic complications between the GH-treated and non-GH-treated groups at T2DM diagnosis. Patients with PWS who develop early T2DM have severe obesity, a high frequency of psychiatric and metabolic disorders, and a family history of T2DM and overweight. These results underline the need for early identification of patients at risk, prevention of obesity, and repeated blood glucose monitoring during the transition period.

Improvement of Planning Abilities in Adults with Prader-Willi Syndrome: A Randomized Controlled Trial

Prader-Willi Syndrome (PWS) is a neurodevelopmental genetic disorder with executive deficits. Planning is one of the impaired executive functions implied in the regulation of behavior and everyday actions. We aimed to explore the feasibility and the effectiveness of a metacognitive strategy training designed to improve planning in adults with PWS using a double-blind between-group (training versus usual care) randomized controlled trial, with computerized tests and paper-pencil ecological outcome measures targeting planning, other executive functions, and achievement of personalized goal. Results showed better performances in several executive tasks and in achievement of personalized goals after both interventions, but better improvement for the experimental group (n = 27) compared to control (n = 26) only on the task assessing planning abilities. Interviews with occupational therapists demonstrated the feasibility of this training with this population. Despite a small number of sessions, the metacognitive strategy training showed encouraging results on planning abilities of patients.

Study of the deficit in planning abilities of adults with Prader-Willi Syndrome

BACKGROUND

Prader-Willi syndrome (PWS) is a complex developmental genetic disorder associated with intellectual disability and deficits in executive functions which result in disorganisation and poor personal autonomy.

AIMS

This study aimed to determine impairments in planning skills of adults with PWS, in relation with their intellectual disabilities, as well as the influence of food compulsions on their performance.

METHODS AND PROCEDURES

A modified version of the Zoo Map from the Behavioural Assessment of the Dysexecutive Syndrome was used in three groups: a group of adults with PWS in comparison with two groups both matched on chronological age, one with typical development (TD) and one with intellectual disability (ID).

OUTCOMES AND RESULTS

Compared to TD adults, both adults with PWS and ID showed increased planning time and lower raw scores on the planning task. The execution time and the number of errors were higher in the PWS group compared to the comparison groups. All three groups performed worse in the non-food condition only for number of errors and raw score.

CONCLUSIONS AND IMPLICATIONS

Planning abilities were impaired in PWS adults. Results also showed that intellectual level plays a role in participants' performance. These findings are essential to understand the difficulties of people with PWS daily life.

Associations Between Hyperphagia, Symptoms of Sleep Breathing Disorder, Behaviour Difficulties and Caregiver Well-Being in Prader-Willi Syndrome: A Preliminary Study

Prader-Willi syndrome (PWS) is a rare genetic disorder characterised by neurodevelopmental delays, hyperphagia, difficulties with social communication and challenging behaviours. Individuals require intensive supervision from caregivers which may negatively affect caregiver quality of life. This study used data collected in the Australasian PWS Registry (n = 50, mean age 11.2 years) to evaluate associations between child behaviours and caregiver mental well-being. Symptoms of sleep-related breathing disorder, child depression and social difficulties were associated with poorer caregiver mental and physical well-being. Growth hormone therapy use was associated with better caregiver mental and physical well-being. Optimising management of problematic behaviours and sleep disturbances have the potential to support caregivers who are the most vital network of support for individuals affected by PWS.

Thyroid Function in Adults with Prader-Willi Syndrome; a Cohort Study and Literature Review

Prader–Willi syndrome (PWS) is a complex genetic syndrome combining hypotonia, hyperphagia, a PWS-specific neurocognitive phenotype, and pituitary hormone deficiencies, including hypothyroidism. The low muscle mass associated with PWS causes a low energy expenditure due to a low basal metabolic rate. Combined with increased energy intake due to hyperphagia, this results in a high risk of obesity and associated cardiovascular disease. To reduce the high mortality in PWS (3% yearly), exercise is extremely important. As hypothyroidism can impair exercise tolerance, early detection is crucial. We performed a literature search for articles on hypothyroidism in PWS, measured thyroid hormone (TH) levels in 122 adults with PWS, and performed a medical file search for medication use. Hypothyroidism (low free thyroxin) was present in 17%, and often central in origin (80%). Triiodothyronine levels were lower in patients who used psychotropic drugs, while other TH levels were similar. One in six patients in our cohort of adults with PWS had hypothyroidism, which is more than in non-PWS adults (3%). We recommend yearly screening of free thyroxin and thyroid-stimulating hormone levels to avoid the negative effects of untreated hypothyroidism on basal metabolic rate, body mass index, and cardiovascular risk. Additionally, we recommend measuring TH concentrations 3–4 months after the start of growth hormone treatment.

Effects of Childhood Multidisciplinary Care and Growth Hormone Treatment on Health Problems in Adults with Prader-Willi Syndrome

Prader-Willi syndrome (PWS) is a complex hypothalamic disorder. Features of PWS include hyperphagia, hypotonia, intellectual disability, and pituitary hormone deficiencies. The combination of growth hormone treatment and multidisciplinary care (GHMDc) has greatly improved the health of children with PWS. Little is known about the effects of childhood GHMDc on health outcomes in adulthood. We retrospectively collected clinical data of 109 adults with PWS. Thirty-nine had received GHMDc during childhood and adolescence (GHMDc+ group) and sixty-three had never received growth hormone treatment (GHt) nor multidisciplinary care (GHMDc− group). Our systematic screening revealed fewer undetected health problems in the GHMDc+ group (10%) than in the GHMDc− group (84%). All health problems revealed in the GHMDc+ group had developed between the last visit to the paediatric and the first visit to the adult clinic and/or did not require treatment. Mean BMI and the prevalence of diabetes mellitus type 2 were significantly lower in the GHMDc+ group compared to the GHMDc− group. As all patients who received GHt were treated in a multidisciplinary setting, it is unknown which effects are the result of GHt and which are the result of multidisciplinary care. However, our data clearly show that the combination of both has beneficial effects. Therefore, we recommend continuing GHMDc after patients with PWS have reached adult age.

Paradoxical low severity of COVID-19 in Prader-Willi syndrome: data from a French survey on 647 patients

BACKGROUND

Patients with Prader-Willi syndrome (PWS) often have comorbidities, especially obesity, that may constitute a risk factor for severe forms of COVID-19. We aimed to assess prevalence and medical course of SARS-CoV-2 infection in children and adults with PWS. From November 2020 to January 2021, we performed a detailed medical survey on 342 adults and 305 children with PWS followed in the French reference center.

RESULTS

We obtained responses from 288 adults (84%) and 239 children (78%). From March 2020 to January 2021, 38 adults (13.2%) and 13 children (5.4%) with PWS had SARS-CoV-2 infection. Mean age of adults was 34.1 ± 11.9 years and mean body mass index was 40.6 ± 12.7 kg/m2; 82% had obesity and 37% had diabetes. Only 3 children (23%) had obesity and none had diabetes. Similar to the general population, the most frequent symptoms of COVID-19 were asthenia, fever, cough, headache and shortness of breath. All patients had a favorable outcome.

CONCLUSION

PWS itself is not a risk factor for severe COVID-19 in children and adults. On the contrary, evolution of SARS-CoV-2 infection in adults with PWS seems more favorable than expected, given their comorbidities.

Altered islet prohormone processing: A cause or consequence of diabetes?

Peptide hormones are first produced as larger precursor prohormones that require endoproteolytic cleavage to liberate the mature hormones. A structurally conserved but functionally distinct family of nine prohormone convertase enzymes (PCs) are responsible for cleavage of protein precursors of which PC1/3 and PC2 are known to be exclusive to neuroendocrine cells and responsible for prohormone cleavage. Differential expression of PCs within tissues define prohormone processing; whereas glucagon is the major product liberated from proglucagon via PC2 in pancreatic α-cells, proglucagon is preferentially processed by PC1/3 in intestinal L cells to produce glucagon-like peptides 1 and 2 (GLP-1, GLP-2). Beyond our understanding of processing of islet prohormones in healthy islets, there is convincing evidence that proinsulin, proIAPP, and proglucagon processing is altered during prediabetes and diabetes. There is predictive value of elevated circulating proinsulin or proinsulin : C-peptide ratio for progression to type 2 diabetes and elevated proinsulin or proinsulin : C-peptide is predictive for development of type 1 diabetes in at risk groups. After onset of diabetes, patients have elevated circulating proinsulin and proIAPP and proinsulin may be an autoantigen in type 1 diabetes. Further, preclinical studies reveal that α-cells have altered proglucagon processing during diabetes leading to increased GLP-1 production. We conclude that despite strong associative data, current evidence is inconclusive on the potential causal role of impaired prohormone processing in diabetes, and suggest that future work should focus on resolving the question of whether altered prohormone processing is a causal driver or merely a consequence of diabetes pathology.

Is ghrelin a biomarker of early-onset scoliosis in children with Prader-Willi syndrome?

Background

Adolescents with idiopathic scoliosis display high ghrelin levels. As hyperghrelinemia is found in patients with PWS and early-onset scoliosis (EOS) is highly prevalent in these patients, our aims were to explore (1) whether ghrelin levels differ between those with and without EOS and correlate with scoliosis severity, and (2) whether ghrelin levels in the first year of life are associated with the later development of EOS.

Methods

We used a case control study design for the first question and a longitudinal design for the second. Patients with PWS having plasma ghrelin measurements recorded between 2013 and 2018 in our database were selected and 30 children < 10 years old with EOS and 30 age- and BMI-matched controls without EOS were included. The Cobb angle at diagnosis was recorded. In addition, 37 infants with a ghrelin measurement in the first year of life were followed until 4 years of age and assessed for EOS. Total ghrelin (TG), acylated (AG) and unacylated ghrelin (UAG), and the AG/UAG ratio were analyzed.

Results

EOS children had an AG/UAG ratio statistically significantly lower than controls. The Cobb angle was positively correlated with TG and UAG. TG and AG in the first year of life were higher in infants who later develop EOS without reaching a statistically significant difference.

Conclusions

Our results suggest that ghrelin may play a role in the pathophysiology of EOS in PWS. Higher ghrelinemia in the first year of life required careful follow-up for EOS.

Hypothalamic neuropeptides and neurocircuitries in Prader Willi syndrome

Prader-Willi Syndrome (PWS) is a rare and incurable congenital neurodevelopmental disorder, resulting from the absence of expression of a group of genes on the paternally acquired chromosome 15q11-q13. Phenotypical characteristics of PWS include infantile hypotonia, short stature, incomplete pubertal development, hyperphagia and morbid obesity. Hypothalamic dysfunction in controlling body weight and food intake is a hallmark of PWS. Neuroimaging studies have demonstrated that PWS subjects have abnormal neurocircuitry engaged in the hedonic and physiological control of feeding behavior. This is translated into diminished production of hypothalamic effector peptides which are responsible for the coordination of energy homeostasis and satiety. So far, studies with animal models for PWS and with human post-mortem hypothalamic specimens demonstrated changes particularly in the infundibular and the paraventricular nuclei of the hypothalamus, both in orexigenic and anorexigenic neural populations. Moreover, many PWS patients have a severe endocrine dysfunction, e.g. central hypogonadism and/or growth hormone deficiency, which may contribute to the development of increased fat mass, especially if left untreated. Additionally, the role of non-neuronal cells, such as astrocytes and microglia in the hypothalamic dysregulation in PWS is yet to be determined. Notably, microglial activation is persistently present in non-genetic obesity. To what extent microglia, and other glial cells, are affected in PWS is poorly understood. The elucidation of the hypothalamic dysfunction in PWS could prove to be a key feature of rational therapeutic management in this syndrome. This review aims to examine the evidence for hypothalamic dysfunction, both at the neuropeptidergic and circuitry levels, and its correlation with the pathophysiology of PWS.

Endocrine disorders in Prader-Willi syndrome: a model to understand and treat hypothalamic dysfunction

Prader-Willi syndrome is a rare genetic neurodevelopmental disorder resulting from the loss of expression of maternally imprinted genes located in the paternal chromosomal region, 15q11-13. Impaired hypothalamic development and function is the cause of most of the phenotypes comprising the developmental trajectory of Prader-Willi syndrome: from anorexia at birth to excessive weight gain preceding hyperphagia, and early severe obesity with hormonal deficiencies, behavioural problems, and dysautonomia. Growth hormone deficiency, hypogonadism, hypothyroidism, premature adrenarche, corticotropin deficiency, precocious puberty, and glucose metabolism disorders are the main endocrine dysfunctions observed. Additionally, as a result of hypothalamic dysfunction, oxytocin and ghrelin systems are impaired in most patients. Standard pituitary and gonadal hormone replacement therapies are required. In this Review, we discuss Prader-Willi syndrome as a model of hypothalamic dysfunction, and provide a comprehensive description of the accumulated knowledge on genetics, pathophysiology, and treatment approaches of this rare disorder.

Clinical management of patients with genetic obesity during COVID-19 pandemic: position paper of the ESE Growth & Genetic Obesity COVID-19 Study Group and Rare Endo-ERN main thematic group on Growth and Obesity

This article aims to provide guidance on prevention and treatment of COVID-19 in patients with genetic obesity. Key principals of the management of patients with genetic obesity during COVID-19 pandemic for patients that have contracted COVID-19 are to be aware of: possible adrenal insufficiency (e.g., POMC deficiency, PWS); a more severe course in patients with concomitant immunodeficiency (e.g., LEP and LEPR deficiency), although defective leptin signalling could also be protective against the pro-inflammatory phenotype of COVID-19; disease severity being masked by insufficient awareness of symptoms in syndromic obesity patients with intellectual deficit (in particular PWS); to adjust medication dose to increased body size, preferably use dosing in m2; the high risk of malnutrition in patients with Sars-Cov2 infection, even in case of obesity. Key principals of the obesity management during the pandemic are to strive for optimal obesity management and a healthy lifestyle within the possibilities of the regulations to prevent weight (re)gain and to address anxiety within consultations, since prevalence of anxiety for COVID-19 is underestimated.

Missed Diagnoses and Health Problems in Adults With Prader-Willi Syndrome: Recommendations for Screening and Treatment

CONTEXT

Prader-Willi syndrome (PWS) is a complex hypothalamic disorder, combining hyperphagia, hypotonia, intellectual disability, and pituitary hormone deficiencies. Annual mortality of patients with PWS is high (3%). In half of the patients, the cause of death is obesity related and/or of cardiopulmonary origin. Health problems leading to this increased mortality often remain undetected due to the complexity and rareness of the syndrome.

OBJECTIVE

To assess the prevalence of health problems in adults with PWS retrospectively.

PATIENTS, DESIGN, AND SETTING

We systematically screened 115 PWS adults for undiagnosed health problems. All patients visited the multidisciplinary outpatient clinic for rare endocrine syndromes at the Erasmus University Medical Center, Rotterdam, Netherlands. We collected the results of medical questionnaires, interviews, physical examinations, biochemical measurements, polygraphy, polysomnography, and radiology.

MAIN OUTCOME MEASURES

Presence or absence of endocrine and nonendocrine comorbidities in relation to living situation, body mass index, genotype, and demographic factors.

RESULTS

Seventy patients (61%) had undiagnosed health problems, while 1 in every 4 patients had multiple undiagnosed health problems simultaneously. All males and 93% of females had hypogonadism, 74% had scoliosis, 18% had hypertension, 19% had hypercholesterolemia, 17% had type 2 diabetes mellitus, and 17% had hypothyroidism. Unfavorable lifestyles were common: 22% exercised too little (according to PWS criteria) and 37% did not see a dietitian.

CONCLUSIONS

Systematic screening revealed many undiagnosed health problems in PWS adults. Based on patient characteristics, we provide an algorithm for diagnostics and treatment, with the aim to prevent early complications and reduce mortality in this vulnerable patient group.

Growth Trajectories in Genetic Subtypes of Prader-Willi Syndrome

Prader–Willi syndrome (PWS) is a rare disorder caused by the loss of expression of genes on the paternal copy of chromosome 15q11-13. The main molecular subtypes of PWS are the deletion of 15q11-13 and non-deletion, and differences in neurobehavioral phenotype are recognized between the subtypes. This study aimed to investigate growth trajectories in PWS and associations between PWS subtype (deletion vs. non-deletion) and height, weight and body mass index (BMI). Growth data were available for 125 individuals with PWS (63 males, 62 females), of which 72 (57.6%) had the deletion subtype. There was a median of 28 observations per individual (range 2–85), producing 3565 data points distributed from birth to 18 years of age. Linear mixed models with cubic splines, subject-specific random effects and an autoregressive correlation structure were used to model the longitudinal growth data whilst accounting for the nature of repeated measures. Height was similar for males in both PWS subtypes, with non-deletion females being shorter than deletion females for older ages. Weight and BMI were estimated to be higher in the deletion subtype compared to the non-deletion subtype, with the size of difference increasing with advancing age for weight. These results suggest that individuals with deletion PWS are more prone to obesity.

Evidence for Accelerated Biological Aging in Young Adults with Prader-Willi Syndrome

OBJECTIVE

Adults with Prader-Willi syndrome (PWS) are at increased risk of developing age-associated diseases early in life and, like in premature aging syndromes, aging might be accelerated. We investigated leukocyte telomere length (LTL), a marker of biological age, in young adults with PWS and compared LTL to healthy young adults of similar age. As all young adults with PWS were treated with growth hormone (GH), we also compared LTL in PWS subjects to GH-treated young adults born short for gestational age (SGA).

DESIGN

Cross-sectional study in age-matched young adults; 47 with PWS, 135 healthy, and 75 born SGA.

MEASUREMENTS

LTL measured by quantitative polymerase chain reaction, expressed as telomere/single copy gene ratio.

RESULTS

Median (interquartile range) LTL was 2.6 (2.4-2.8) at a median (interquartile range) age of 19.2 (17.7-21.3) years in PWS, 3.1 (2.9-3.5) in healthy young adults and 3.1 (2.8-3.4) in the SGA group. Median LTL in PWS was significantly lower compared to both control groups (P < .01). In PWS, a lower LTL tended to be associated with a lower total IQ (r = 0.35, P = .08). There was no association between LTL and duration of GH treatment, cumulative GH dose, or several risk factors for type 2 diabetes mellitus or cardiovascular disease.

CONCLUSIONS

Young adults with PWS have significantly shorter median LTL compared to age-matched healthy young adults and GH-treated young adults born SGA. The shorter telomeres might play a role in the premature aging in PWS, independent of GH. Longitudinal research is needed to determine the influence of LTL on aging in PWS.

Update on Diabetes Mellitus and Glucose Metabolism Alterations in Prader-Willi Syndrome

PURPOSE OF REVIEW

This review summarizes our current knowledge on type 2 diabetes mellitus (T2DM) and glucose metabolism alterations in Prader-Willi syndrome (PWS), the most common syndromic cause of obesity, and serves as a guide for future research and current best practice.

RECENT FINDINGS

Diabetes occurs in 10-25% of PWS patients, usually in adulthood. Severe obesity is a significant risk factor for developing of T2DM in PWS. Paradoxically, despite severe obesity, a relative hypoinsulinemia, without the expected insulin resistance, is frequently observed in PWS. The majority of PWS subjects with T2DM are asymptomatic and diabetes-related complications are infrequent. Long-term growth hormone therapy does not adversely influence glucose homeostasis in all ages, if weight gain does not occur. Early intervention to prevent obesity and the regular monitoring of glucose levels are recommended in PWS subjects. However, further studies are required to better understand the physiopathological mechanisms of T2DM in these patients.

Cognitive Training Targeting Planning Dysfunction in Adults with Prader-Willi Syndrome: Brief Report of a Study Protocol

Background: Prader-Willi syndrome (PWS) is a neurodevelopmental genetic disorder involving executive deficits notably with planning. The main objective of the study is to assess the effectiveness of cognitive training on daily life planning difficulties in PWS patients. Methods/design: The study is a double-blind randomized controlled trial which will compare the effectiveness of a metacognitive strategy intervention designed to improve planning difficulties for PWS patients to usual occupational therapy. Sixty adults will be included over 20 months. The main outcome measure will be the performance on the Modified Six Elements Test from the BADS; secondary outcome measures will be computerized executive tasks and questionnaires. Daily life planning difficulties will be identified and transformed into measurable goals using Goal Attainment Scaling. Discussion: The project will provide knowledge on the difficulties experienced by PWS patients, in relation to their executive functioning in order to implement effective intervention for planning in daily life.

Guanfacine Extended Release for the Reduction of Aggression, Attention-Deficit/Hyperactivity Disorder Symptoms, and Self-Injurious Behavior in Prader-Willi Syndrome-A Retrospective Cohort Study

Objective: To examine the role of Guanfacine Extended Release (GXR) in the management of behavioral disturbances in patients with Prader-Willi Syndrome (PWS). Methods: Twenty from a total of 27 individuals with genetically confirmed PWS, 6-26 years of age, with the following symptoms were identified: significant aggression/agitation, skin picking, and/or symptoms of attention-deficit/hyperactivity disorder (ADHD). Response to GXR for the above noted symptoms was categorized as improved, worsened, or unchanged, while assessing for side effects and tolerability. Results: Eleven of the 20 individuals reported skin-picking, 17 reported aggression/agitation, and 16 reported symptoms of ADHD. Nine (81.8%), 14 (82.3%), and 15 (93.7%) individuals showed an improvement in skin-picking, aggression/agitation, and ADHD, respectively, while on GXR treatment. Two patients with prior complaints of psychotic symptoms did not respond to GXR. Of note, no abnormal weight gain or significant adverse reaction was observed in this group, while on GXR. Conclusions: In this study, GXR demonstrated improvement in symptoms of skin picking, aggression/agitation, and ADHD in patients with PWS. GXR was not effective in reducing psychosis or agitation related to psychotic symptoms. Future studies are warranted to further establish the utility of GXR in PWS patients.

Is strength training feasible for young people with Prader-Willi syndrome? A phase I randomised controlled trial

OBJECTIVE

To investigate the feasibility of progressive resistance training for people with Prader-Willi syndrome (PWS), who have muscle weakness and very low muscle mass.

DESIGN

Randomised controlled trial with concealed allocation, assessor blinding and intention-to-treat analysis.

SETTING

Community gymnasium.

PARTICIPANTS

Sixteen participants with PWS (eight female; mean age 25 years) were randomly assigned with 1:1 allocation to an experimental (n=8) or control group (n=8).

INTERVENTION

Progressive resistance training was performed twice a week for 10 weeks. The training was supervised one-to-one by a physiotherapist and comprised seven exercises. The control group continued their usual activities and were offered the training after follow-up assessment.

MAIN OUTCOME MEASURES

Three domains of feasibility were evaluated: implementation (attendance and adherence), practicality (safety) and limited efficacy testing. Muscle strength (one repetition maximum for chest and leg press), physical function (box stacking test, timed stairs climb), muscle composition (US) and body composition (whole-body DXA scan) were measured before and after the intervention.

RESULTS

Participants attended 92% of scheduled sessions and adhered by progressing their training resistance by 82% (range 60-140%). There was one unexpected serious adverse event unrelated to the intervention and several non-serious expected adverse events related to the intervention. Estimates of standardised mean differences indicated moderate to large effects in favour of the experimental group for arm (0.92, 95%CI -0.11 to 1.95) and leg strength (0.78, 95%CI -0.27 to 1.83). The effect was uncertain for secondary outcomes.

CONCLUSIONS

There is preliminary evidence showing progressive resistance training is feasible for people with Prader-Willi syndrome and may increase muscle strength. Clinical Trial Registration Australia New Zealand Clinical Trials Registry ACTRN12616000107426.

Investigation of the relationship between electrodermal and behavioural responses to executive tasks in Prader-Willi syndrome: An event-related experiment

BACKGROUND

Recent work suggests that maladaptive behaviors in genetic developmental disorders may emerge from autonomic dysfunctions impacting higher order executive functions. In Prader-Willi syndrome (PWS), executive functions are not well understood and investigations of possible underlying causes at the autonomic level are lacking.

AIMS

This study aimed at clarifying the status of inhibition and working memory updating functions in PWS and searched for sympathetic signatures as well as to examine their links with executive performance.

METHODS AND PROCEDURES

The performance of thirty adults with PWS was compared to that of thirty healthy adults on two tasks assessing inhibition and working memory updating while electrodermal activity (EDA) was recorded.

OUTCOMES AND RESULTS

PWS adults underperformed healthy adults in the inhibition and the working memory updating tasks and showed abnormal skin conductance responses. Distinct EDA have been found in PWS and healthy adults. Furthermore, while EDA reflected distinct cognitive processes, correlations between electrodermal and behavioural data were absent when examining the two groups separately.

CONCLUSIONS AND IMPLICATIONS

PWS is associated with a slight impairment of inhibition and a severe impairment of working memory updating. Furthermore, there are specific sympathetic autonomic signatures in PWS that do not present straightforward links with executive dysfunctions.

Contributing factors of mortality in Prader-Willi syndrome

Prader-Willi syndrome (PWS) is a multi-system disorder resulting from a lack of paternal gene expression in the 15q11.2-q13 region. Using databases compiled through response questionnaires completed by families known to the Prader-Willi Syndrome Association (USA), this study tested the hypothesis that PWS genetic subtype, BMI, age of diagnosis, clinical symptoms, and growth hormone treatment differ among deceased and living individuals with PWS. Categorical and continuous variables were compared using chi-square and two-group t tests, respectively. Deceased individuals had higher rates of clinical features, including increased weight concerns, heart problems, sleep apnea, other respiratory complications, diabetes, osteoporosis, high pain tolerance, and severe skin picking, when compared to living individuals. Meanwhile, living individuals had higher rates of growth hormone use and early puberty. Obesity and subsequent consequences are the primary contributors to increased mortality in PWS. Additional emphasis on areas to decrease mortality is needed.

Less known aspects of central hypothyroidism: Part 2 - Congenital etiologies

Central hypothyroidism (CH) occurs approximately in 1:50,000, and therefore is expected to be one thousand times rarer compared with primary hypothyroidism. Despite its rarity in the general population, it is much more common in certain disorders, in which it is frequently associated with other pituitary hormone deficiencies. The aim of this paper is to provide an updated review on the frequency of congenital CH, which is <1:50,000, and on its etiology, disregarding CH caused by other genetic defects, such as mutations of transcription factors involved in pituitary organogenesis or mutations of the genes encoding TRH or TRH receptor.

AZP-531, an unacylated ghrelin analog, improves food-related behavior in patients with Prader-Willi syndrome: A randomized placebo-controlled trial

Context and objective

Prader-Willi syndrome (PWS) is characterized by early-onset hyperphagia and increased circulating levels of the orexigenic Acylated Ghrelin (AG) hormone with a relative deficit of Unacylated Ghrelin (UAG). AZP-531, a first-in-class UAG analog, was shown to inhibit the orexigenic effect of AG in animals, to improve glycemic control and decrease body weight in humans. We aimed to investigate the safety and efficacy of AZP-531 in patients with PWS for whom no approved treatment for hyperphagia is currently available.

Methods and design

Multi-center, randomized, double-blind, placebo-controlled trial. Forty-seven patients with genetically confirmed PWS and evidence of hyperphagia received daily subcutaneous injections of AZP-531 (3 and 4 mg for 50–70 kg and >70 kg body weight, respectively) or matching placebo for 14 days. Assessments included adverse events, vital signs, safety laboratory tests, the Hyperphagia Questionnaire (HQ), patient-reported appetite, body composition and glycemic measures.

Results

AZP-531 was well tolerated. There was a significant improvement with AZP-531 versus placebo in the mean total score, the 9-item score and the severity domain score of the HQ (p < .05). The highest reduction in the total and 9-item scores was observed in AZP-531 subjects with the highest hyperphagia score at baseline. Findings were supported by a reduction in appetite scores observed with AZP-531 only. Body weight did not change in both groups while a significant reduction in waist circumference and fat mass was observed only with AZP-531. AZP-531 significantly decreased post-prandial glucose levels in a baseline glucose dependent fashion.

Conclusions

AZP-531 may constitute a new treatment strategy to improve hyperphagia and metabolic issues in patients with PWS. These findings support further investigation in longer-term clinical trials.

Obesity management in Prader-Willi syndrome: current perspectives

Prader-Willi syndrome (PWS) is a complex multisystem disorder due to the absent expression of the paternally active genes in the PWS critical region on chromosome 15 (15q11.2-q13). The syndrome is considered the most common genetic cause of obesity, occurring in 1:10,000-1:30,000 live births. Its main characteristics include neonatal hypotonia, poor feeding, and lack of appetite in infancy, followed by weight gain, lack of satiety, and uncontrolled appetite, frequently after the age of 2-3 years. The clinical picture includes short stature, multiple endocrine abnormalities (hypogonadism, growth hormone/insulin-like growth factor-I axis dysfunction, hypothyroidism, central adrenal insufficiency), dysmorphic features, scoliosis, osteoporosis, mental retardation, and behavioral and psychiatric problems. Subjects with PWS will become severely obese unless their food intake is strictly controlled. Constant and obsessive food seeking behavior can make life very difficult for both the family and caretakers. Prevention of obesity is mandatory in these patients from the first years of life, because once obesity develops it is difficult to maintain the control of food intake. In fact, PWS subjects die prematurely from complications conventionally related to obesity, including diabetes mellitus, metabolic syndrome, sleep apnea, respiratory insufficiency, and cardiovascular disease. The mechanisms underlying hyperphagia in PWS are not completely known, and to date no drugs have proven their efficacy in controlling appetite. Consequently, dietary restriction, physical activity, and behavior management are fundamental in the prevention and management of obesity in PWS. In spite of all available therapeutic tools, however, successful weight loss and maintenance are hardly accomplished. In this context, clinical trials with new drugs have been initiated in order to find new possibilities of a therapy for obesity in these patients. The preliminary results of these studies seem to be encouraging. On the other hand, until well-proven medical treatments are available, bariatric surgery can be taken into consideration, especially in PWS patients with life-threatening comorbidities.

Metabolic health profile in young adults with Prader-Willi syndrome: results of a 2-year randomized, placebo-controlled, crossover GH trial

CONTEXT

Patients with Prader-Willi syndrome (PWS) have an increased fat mass and decreased lean body mass. GH-treated young adults with PWS who have attained adult height benefit from continuation of growth hormone (GH) treatment, as GH maintained their improved body composition, whereas fat mass increased during the placebo period. Adults with PWS are predisposed to T2DM and cardiovascular disease. Whether GH affects metabolic health profile of this patient group is unknown.

OBJECTIVE

To investigate the effects of GH vs placebo on metabolic health, in young adults with PWS who were GH-treated for many years during childhood and had attained adult height (AH).

METHOD

A 2-year, randomized, double-blind, placebo-controlled crossover study with stratification for gender and BMI in 27 young adults with PWS. Intervention with GH (0·67 mg/m² /day) and placebo, both for 1-year duration.

RESULTS

Compared to placebo, GH treatment resulted in similar glucose and insulin levels during oral glucose tolerance test. Only fasting glucose and insulin were slightly higher during GH vs placebo (+0·2 mmol/l and +18·4 pmol/l), although both remained within normal ranges in both phases. Blood pressure and lipid profile were similar after GH vs placebo. At baseline (AH) and during GH, no patients had metabolic syndrome, while 1 developed it during placebo treatment.

CONCLUSIONS

Growth hormone treatment has no adverse effects on metabolic health profile. Thus, GH-treated young adults with PWS who have attained AH benefit from continuation of GH treatment without safety concerns regarding metabolic health.

Economic burden and health-related quality of life associated with Prader-Willi syndrome in France

BACKGROUND

To date, there has been no published comprehensive estimation of costs related to Prader-Willi syndrome (PWS). Our objective was therefore to provide data on the economic burden and health-related quality of life associated with PWS in France in order to raise awareness of the repercussions on individuals suffering from this syndrome and on caregivers as well as on the health and social care systems.

METHOD

A retrospective cross-sectional study was carried out on 51 individuals recruited through the French PWS patient association. Data on their demographic characteristics and resource use were obtained from an online questionnaire, and costs were estimated by a bottom-up approach. The EQ-5D-5L health questionnaire was used to measure the health-related quality of life of individuals suffering from PWS and their caregivers.

RESULTS

The average annual cost of PWS was estimated at €58 890 per individual, with direct healthcare accounting for €42 299, direct non-healthcare formal costs €13 865 and direct non-healthcare informal costs €8459. The main contributors to PWS costs were hospitalisations and social services. Indirect costs resulting from loss of productivity in the labour market was €32 542 for adults suffering from PWS. Mean EQ-5D utility scores were 0.4 for individuals with PWS and 0.7 for caregivers.

CONCLUSIONS

Prader-Willi syndrome represents a major economic burden from a societal perspective and has a significant impact on health-related quality of life both for individuals suffering from PWS and for their caregivers in France. These results underscore the need to develop tailored policies targeted at improving care. Likewise, a larger study collecting a broader range of medical characteristics should be undertaken to achieve more precise estimations.

Disorders of glucose metabolism in Prader-Willi syndrome: Results of a multicenter Italian cohort study

BACKGROUND AND AIMS

Prader-Willi syndrome (PWS) is characterized by a high incidence of altered glucose metabolism (AGM). However, epidemiological data on impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM) are still discordant.

METHODS AND RESULTS

We performed a multicenter study based on 274 PWS patients [144 females, aged 20.3 ± 10.4 yrs (range: 8.1-50.1 years)] evaluating the prevalence for AGM in the entire group, and according to age (children <10 yrs; adolescents 10-18 yrs, and adults >18 yrs), Body Mass Index (BMI = kg/m(2)), gender, genotypes (deletion or uniparental disomy for chromosome 15), and GH therapy (GHT) (untreated, previously or currently treated). Altogether, AGM was detected in 67 (24.4%) of patients (0.7% IFG, 10.2% IGT, 13.5% T2DM). The prevalence of AGM was correlated to age (p = 0.001), BMI (p = 0.001) and HOMA-IR (p = 0.001). However, gender, genotype, and GHT did not influence AGM development in univariate analysis. These data were confirmed as positive predictors when inserted in a multivariate analysis model.

CONCLUSION

This study is the first report on the prevalence of AGM in a large population of PWS. Overall, PWS subjects show a high prevalence of AGM that appears more common in obese and adult subjects. Our data confirm the main role of obesity on the individual metabolic risk clustering in PWS, and thus reinforce the concept that improvement in weight control remains the most important goal of any PWS treatment program.

Medication Trials for Hyperphagia and Food-Related Behaviors in Prader-Willi Syndrome

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder caused by the absence of paternally expressed, imprinted genes on chromosome 15q11-13. Individuals with PWS characteristically have poor feeding and lack of appetite in infancy, followed by the development of weight gain and then uncontrolled appetite and lack of satiety, sometime after the age of two. The overwhelming drive to eat is coupled with reduced energy expenditure and decreased caloric requirements, thus, individuals with PWS will become severely obese unless their food intake is strictly controlled. The mechanisms underlying hyperphagia in PWS remain incompletely understood, and to date no drugs have proven effective in controlling appetite. However, clinical trials have started for several medications, which may provide therapeutic options for those with PWS. These medication trials may also provide insight into potential treatments for obesity in the general population. Ideally, these treatments will help alleviate the complex metabolic issues that are part of this syndrome.

Patterns of Risk for Multiple Co-Occurring Medical Conditions Replicate Across Distinct Cohorts of Children with Autism Spectrum Disorder

Children with autism spectrum disorder (ASD) may present with multiple medical conditions in addition to ASD symptoms. This study investigated whether there are predictive patterns of medical conditions that co-occur with ASD, which could inform medical evaluation and treatment in ASD, as well as potentially identify etiologically meaningful subgroups. Medical history data were queried in the multiplex family Autism Genetic Resource Exchange (AGRE). Fourteen medical conditions were analyzed. Replication in the Simons Simplex Collection (SSC) was attempted using available medical condition data on gastrointestinal disturbances (GID), sleep problems, allergy and epilepsy. In the AGRE cohort, no discrete clusters emerged among 14 medical conditions. GID and seizures were enriched in unaffected family members, and together with sleep problems, were represented in both AGRE and SSC. Further analysis of these medical conditions identified predictive co-occurring patterns in both samples. For a child with ASD, the presence of GID predicts sleep problems and vice versa, with an approximately 2-fold odds ratio in each direction. These risk patterns were replicated in the SSC sample, and in addition, there was increased risk for seizures and sleep problems to co-occur with GID. In these cohorts, seizure alone was not predictive of the other conditions co-occurring, but behavioral impairments were more severe as the number of co-occurring medical symptoms increased. These findings indicate that interdisciplinary clinical care for children with ASD will benefit from evaluation for specific patterns of medical conditions in the affected child and their family members.