Cross-cultural comparisons of obesity and growth in Prader-Willi syndrome

Quality of Life for Adults with Prader-Willi Syndrome in Residential Group Homes

Background: Strict regimens of restricted caloric intake and daily physical exercise are life-saving in Prader-Willi syndrome (PWS) but are extremely challenging in home environments. PWS-specialized hostels (SH) succeed in preventing morbid obesity and in coping with behavioral disorders; however, effects of restricted living environments on quality of life (QOL) have not been described. Evidence on QOL is critical for clinicians involved in placement decisions. Methods: We examined the impact of living in SH versus at home or in non-specialized hostels (H and NSH) on QOL, behavior, and health parameters. All 58 adults (26 males) followed-up in the National Multidisciplinary Clinic for PWS were included: 33 resided in SH, 18 lived at home, and 7 lived in NSH. Questionnaires were administered to primary caregivers to measure QOL, and data were obtained from the medical records. Results: The H and NSH group were compared with those for adults in SH. Despite strict diet and exercise regimens, QOL was similar for both groups. Eight-year follow-up showed that food-seeking behavior decreased in SH but increased in H and NSH. BMI, cholesterol, and triglyceride levels were lower in SH. Conclusion: Our results suggest that living in SH is associated with benefits for physical health and behavior without negatively affecting QOL.

Demographics and medical comorbidities among hospitalized patients with Prader-Willi Syndrome: A National Inpatient Sample analysis

Prader-Willi Syndrome (PWS) is a multi-system genetic disorder characterized by hyperphagia and a range of medical complications. While register and cohort studies have explored the natural course of the syndrome, there is little nationally-representative data. In this study the National Inpatient Sample, a de-identified all-payors database of acute care hospital discharges in the United States, was queried for patients discharged with a diagnosis of PWS in 2019. Hospitalizations involving PWS were compared to hospitalizations without a PWS diagnosis matched based on demographic and hospital factors. In total, 540 hospitalizations (95% CI: 513-567) included a diagnosis of PWS. Median age at time of admission was 22 years, with an interquartile range of 6.3-37.8 years. Respiratory conditions accounted for 110 (20.4%) of primary discharge diagnoses, with infectious conditions for 70 (13.0%) and digestive conditions for 65 (12.0%). Hospitalizations involving PWS were significantly more likely to involve respiratory failure (OR 5.49; 95% CI 3.86-7.80), septicemia (OR 2.80, 95% CI 1.97-3.96), or intestinal obstruction and ileus (OR 6.29; 95% CI 3.70-10.7) compared to matched hospitalizations without PWS. Obesity was diagnosed in 230 PWS hospitalizations (42.6%; OR 3.86, 95% CI 3.17-4.72 relative to non-PWS hospitalizations). These results point to an ongoing need for the improved diagnosis and treatment of PWS complications, and highlight the importance of specific billing codes for rare diseases to enhance the collection of real world evidence.

Long-term weight control in adults with Prader-Willi syndrome living in residential hostels

Hyperphagia leading to severe obesity with increased morbidity and mortality is the major manifestation of Prader-Willi syndrome. Caring for these individuals in a home environment is challenging and stressful for caregivers and families. Residential hostels specifically for PWS adults offer programs of diet, exercise, and vocational opportunities, but long-term effects of PWS hostel living have not been reported. We studied long-term changes in body mass index (BMI) for PWS adults living in residential hostels compared with age-matched controls living with families at home. The study included all 34 individuals (18 men) aged >17 years with genetically confirmed PWS living in residential hostels. BMI was recorded at the time of yearly clinic visits and compared to 23 PWS adults (10 men) living at home. BMI on entering the hostel was 36.3 ± 11.0 kg/m² and decreased to 27.0 ± 5.6 kg/m² (p < 0.001) after 6.9 ± 3.9 years. For 21 residents, a slight rise of BMI to 28.8 kg/m² was observed 5.1 ± 2.5 years after the lowest value was achieved. BMI of 23 PWS adults at home was 36.8 ± 12.7 kg/m² versus 27.9 ± 7.1 kg/m² for hostel residents in the same age range (p = 0.008). From 2008 to 2019, there were five deaths among PWS individuals aged 18-40 years living at home, compared with one death (a 43-year-old man) among hostel residents. Adults with PWS living in hostels lose weight, maintain BMI values in a normal to mildly overweight range, and have lower mortality in contrast to individuals in a family home environment.

Variability and change over time of weight and BMI among adolescents and adults with Prader-Willi syndrome: a 6-month text-based observational study

BACKGROUND

Prader-Willi syndrome (PWS) is a rare neurodevelopmental disorder in which hyperphagia (excessive appetite) is a hallmark feature. Understanding how weight changes over time in this population is important for capturing the contemporary natural history of the disorder as well as assessing the impact of new treatments for hyperphagia. Therefore, we aimed to determine the feasibility of a remote assessment of weight change over time in PWS.

METHODS

We developed a text message-based, prospective cohort study of adolescents and adults with PWS to assess changes in weight and body mass index (BMI) over a six-month period. Weight was collected weekly, while changes in height, living situation, access to food, activity level, and medication were collected at three-month intervals.

RESULTS

One hundred and sixty-five participants enrolled in the study, with a mean age of 19.7 years (range 12-48). There was considerable variability in weight across participants (range: 76.8-207.7 kg). Thirty-three percent of the participants were normal weight, while 15% were overweight and 52% were obese. Overall, the weight of the study participants increased over the study period (mean weight change + 2.35%), while BMI was relatively stable, albeit high (mean BMI of 31.4 at baseline, mean BMI percent change + 1.42%). Changes in living situation, activity, food access, and medication had limited impact on weight and BMI changes. Multivariable analysis found that time, sex, age, and percentage of life on growth hormone (GH) therapy were statistically significant fixed effects. Participants submitted more than 95% of possible weight data points across the 26 weeks of the study.

CONCLUSIONS

This remote, observational study of weight change in PWS showed small increases in weight and BMI over a six-month period. Participants were highly compliant with this text message-based study, suggesting that mobile technology-based data collection was manageable for the participants. We anticipate that the results of this study will inform clinical trials for hyperphagia/obesity related therapies in PWS and provide a basis for understanding the efficacy of new therapies for hyperphagia in the real-world setting.

Thyroid function in patients with Prader-Willi syndrome: an Italian multicenter study of 339 patients

Background Prader-Willi syndrome (PWS) is a genetic disorder due to loss of expression of paternally transcribed genes of the imprinted region of chromosome 15q11-13. PWS is characterized by peculiar signs and symptoms and many endocrine abnormalities have been described (growth hormone deficiency, hypogonadotropic hypogonadism). The abnormalities of thyroid function are discussed in literature and published data are discordant. The aim of our study was to report the thyroid function in patients with PWS to identify the prevalence of thyroid dysfunction. Methods Thyroid function tests were carried out in 339 patients with PWS, aged from 0.2 to 50 years. A database was created to collect personal data, anthropometric data, thyroid function data and possible replacement therapy with L-thyroxine. Subjects were classified according to thyroid function as: euthyroidism (EuT), congenital hypothyroidism (C-HT), hypothyroidism (HT - high thyroid-stimulating hormone [TSH] and low free thyroxine [fT4]), central hypothyroidism (CE-H - low/normal TSH and low fT4), subclinical hypothyroidism (SH - high TSH and normal fT4), and hyperthyroidism (HyperT - low TSH and high fT4). Results Two hundred and forty-three out of 339 PWS patients were younger than 18 years (71.7%). The prevalence of thyroid dysfunction was 13.6%. Specifically, C-HT was found in four children (1.18%), HT in six patients (1.77%), CE-H in 23 patients (6.78%), SH in 13 patients (3.83%), and HyperT in none. All other subjects were in EuT (86.4%). Conclusions Hypothyroidism is a frequent feature in subjects with PWS. Thyroid function should be regularly investigated in all PWS patients both at the diagnosis and annually during follow-up.

Gene-nutrient interactions and susceptibility to human obesity

A large number of genome-wide association studies, transferability studies, and candidate gene studies performed in diverse populations around the world have identified gene variants that are associated with common human obesity. The mounting evidence suggests that these obesity gene variants interact with multiple environmental factors and increase susceptibility to this complex metabolic disease. The objective of this review article is to provide concise and updated information on energy balance, heritability of body weight, origins of gene variants, and gene-nutrient interactions in relation to human obesity. It is proposed that knowledge of these related topics will provide valuable insight for future preventative lifestyle intervention using targeted nutritional and medicinal therapies.

The importance of gene-environment interactions in human obesity

The worldwide obesity epidemic has been mainly attributed to lifestyle changes. However, who becomes obese in an obesity-prone environment is largely determined by genetic factors. In the last 20 years, important progress has been made in the elucidation of the genetic architecture of obesity. In parallel with successful gene identifications, the number of gene-environment interaction (GEI) studies has grown rapidly. This paper reviews the growing body of evidence supporting gene-environment interactions in the field of obesity. Heritability, monogenic and polygenic obesity studies provide converging evidence that obesity-predisposing genes interact with a variety of environmental, lifestyle and treatment exposures. However, some skepticism remains regarding the validity of these studies based on several issues, which include statistical modelling, confounding, low replication rate, underpowered analyses, biological assumptions and measurement precision. What follows in this review includes (1) an introduction to the study of GEI, (2) the evidence of GEI in the field of obesity, (3) an outline of the biological mechanisms that may explain these interaction effects, (4) methodological challenges associated with GEI studies and potential solutions, and (5) future directions of GEI research. Thus far, this growing body of evidence has provided a deeper understanding of GEI influencing obesity and may have tremendous applications in the emerging field of personalized medicine and individualized lifestyle recommendations.

Overweight and obesity in youth with developmental disabilities: a call to action

Elevated weight status has become a leading problem for adults and children around the world, regardless of the presence or lack of disability. Youth with intellectual and developmental disabilities are more vulnerable than the typical population to overweight in recent decades, and these individuals often experience overweight and obesity at higher rates than their typically developing peers. Young people with disabilities have many circumstances, beyond those of typically developing children, which increase their risk for greater body mass. These include greater medication use, having syndromes with obesity as an associated symptom, and possessing altered eating habits related to their disability. We discuss obesity-related health risks, possible weight management options, recommendations for weight maintenance or loss, and future research. Although most professionals who work with youth having developmental disabilities do not have great expertise in nutrition and weight management, we must collectively recognise the importance of weight issues for quality of life of these individuals and work with them in maintaining healthy lifestyles. Intervention options, both for caregivers and for health professionals, are discussed.

Body mass index of adults with intellectual disability participating in Special Olympics by world region

BACKGROUND

People with intellectual disability (ID) experience poorer health and have more unmet health needs compared with people without ID, and they are often absent from population health surveillance. The aim of this study was to describe the body mass index (BMI) status of adult Special Olympics participants by world region and gender. Additionally, the general influence of age and gender on overweight/obesity of all participants was explored.

METHOD

A total of 11 643 (7150 male and 4493 female) Special Olympics BMI records were available from the Special Olympics International Health Promotion database. BMI was compared by gender and world region. Logistic regression was used to examine whether age and gender were associated with the likelihood of being overweight/obese (BMI ≥ 25.0).

RESULTS

Overall, 5.5% of the sample was underweight, 36.1% in the normal range, 24.7% overweight and 32.1% obese, and levels of overweight/obesity were very high in North America. Both age and gender were significant predictors of overweight/obesity (odds ratios 1.06 and 0.59, respectively).

CONCLUSIONS

Our findings demonstrate that adult Special Olympics participants have high levels of overweight and obesity; particularly among women and those from North America. It is crucial that those who work with, care for, coach and live with adults with ID who participate in Special Olympics increase efforts to promote healthy weight status.

The European Prader-Willi Syndrome Clinical Research Database: an aid in the investigation of a rare genetically determined neurodevelopmental disorder

BACKGROUND

Prader-Willi Syndrome (PWS) is a rare genetically determined neurodevelopmental disorder with a complex phenotype that changes with age. The rarity of the syndrome and the need to control for different variables such as genetic sub-type, age and gender limits clinical studies of sufficient size in any one country. A clinical research database has been established to structure data collection and to enable multinational investigations into the development of children and adults with PWS.

METHODS

As part of a joint basic science and clinical study of PWS funded through Framework 6 of the European Union (EU), an expert multidisciplinary group was established that included clinicians involved in PWS research and clinical practice, expert database software developers, and representatives from two national PWS Associations. This group identified the key issues that required resolution and the data fields necessary for a comprehensive database to support PWS research.

RESULTS

The database consists of six 'index' entry points and branching panels and sub-panels and over 1200 data 'fields'. It is Internet-based and designed to support multi-site clinical research in PWS. An algorithm ensures that participant data are anonymous. Access to data is controlled in a manner that is compatible with EU and national laws. The database determines the assessments to be used to collect data thereby enabling the combining of data from different groups under specifically agreed conditions. The data collected at any one time will be determined by individual research groups, who retain control of the data. Over time the database will accumulate data on participants with PWS that will support future research by avoiding the need for repeat data collection of fixed data and it will also enable longitudinal studies and treatment trials.

CONCLUSION

The development of the database has proved to be complex with various administrative and ethical issues to be addressed. At an early stage, it was important to clarify the exact function of the database. It was agreed that it was primarily to support grant-funded research rather than clinical practice. The most complex issues that had to be addressed were concerned with data ownership and establishing the rules for data entry, retrieval and sharing that are compatible with data protection laws, and which are likely to be acceptable to participants and their families and to individual research groups.