Resting energy expenditure and adiposity accretion among children with Down syndrome: a 3-year prospective study

Endocrine, auxological and metabolic profile in children and adolescents with Down syndrome: from infancy to the first steps into adult life

Down syndrome (DS) is the most common chromosomal disorder worldwide. Along with intellectual disability, endocrine disorders represent a remarkable share of the morbidities experienced by children, adolescents and young adults with DS. Auxological parameters are plotted on syndrome-specific charts, as growth rates are reduced compared to healthy age- and gender-matched peers. Furthermore, children with DS are at increased risk for thyroid dysfunctions, diabetes mellitus, osteopenia and obesity compared to general population. Additionally, male individuals with DS often show infertility, while women tend to experience menopause at an overall younger age than healthy controls. Given the recent outstanding improvements in the care of severe DS-related comorbidities, infant mortality has dramatically decreased, with a current average life expectancy exceeding 60 years. Accordingly, the awareness of the specificities of DS in this field is pivotal to timely detect endocrine dysfunctions and to undertake a prompt dedicated treatment. Notably, best practices for the screening and monitoring of pediatric endocrine disorders in DS are still controversial. In addition, specific guidelines for the management of metabolic issues along the challenging period of transitioning from pediatric to adult health care are lacking. By performing a review of published literature, we highlighted the issues specifically involving children and adolescent with DS, aiming at providing clinicians with a detailed up-to-date overview of the endocrine, metabolic and auxological disorders in this selected population, with an additional focus on the management of patients in the critical phase of the transitioning from childhood to adult care.

Physical Activity in Youth with Down Syndrome and Its Relationship with Adiposity

PURPOSE

The aims of this study are to (1) compare physical activity (PA) and sedentary activity (SA) in youth with and without Down syndrome (DS and non-DS) and examine the relationships of PA and SA with their traditional risk factors (age, sex, race, and body mass index Z score [BMI-Z]) and (2) explore the relationship of PA with visceral fat (VFAT) in both groups.

METHODS

SenseWear accelerometry data from at least 2 weekdays and 1 weekend day were collected from youth with DS (N = 77) and non-DS (N = 57) youth. VFAT was measured by dual x-ray absorptiometry.

RESULTS

In age-, sex-, race-, and BMI-Z-adjusted models, those with DS engaged in more minutes of light PA (LPA) ( p < 0.0001) and less SA ( p = 0.003) and trended toward fewer minutes of moderate-to-vigorous PA (MVPA) ( p = 0.08) than non-DS youth. No race or sex differences in MVPA were detected in those with DS, unlike non-DS. After additional adjustment for pubertal status, the relationship between MVPA and VFAT approached significance ( p = 0.06), whereas the relationships of LPA and SA with VFAT were maintained ( p ≤ 0.0001 for both).

CONCLUSION

Youth with DS engage in more LPA compared with non-DS, which, in typically developing populations, can confer a more favorable weight status. Increasing the opportunity for youth with DS to engage in LPA as part of their activities of daily living may offer a viable strategy for achieving healthy weight when barriers restrict pursuit of more vigorous PA.

Energy expenditure and weight-related behaviors in youth with Down syndrome: a protocol

Background

The consequences of obesity are ominous, yet healthcare professionals are not adequately preventing or treating obesity in youth with Down syndrome (DS). Total daily energy expenditure (TDEE) is the energy expended in 24 h through physical activity and life-sustaining physiologic processes. An individual's TDEE is essential for determining the daily caloric intake needed to maintain or change body weight. Successful prevention and treatment of obesity in youth with DS is severely compromised by the lack of data on TDEE and information on weight-related behaviors for this high-risk population. This manuscript describes the protocol for the federally funded study that is in process to determine daily energy expenditure in a large cohort of children with DS.

Methods

This observational cross-sectional study will include a national sample of 230 youth with DS, stratified by age (5-11 and 12-18 years of age) and sex. Doubly Labeled Water analysis will provide the criterion body fat%, fat-free mass, and TDEE. To increase accessibility and decrease the burden on participants, the entire study, including obtaining consent and data collection, is conducted virtually within the participant's home environment on weekdays and weekends. The study team supervises all data collection via a video conferencing platform, e.g., Zoom. This study will (1) examine and determine average TDEE based on age and sex, (2) develop a prediction equation based on measured TDEE to predict energy requirements with a best-fit model based on fat-free mass, sex, age, and height and/or weight, and (3) use 24-hour dietary recalls, a nutrition and physical activity screener, wearable devices, and sleep questionnaire to describe the patterns and quality of dietary intake, sleep, and physical activity status in youth with DS.

Discussion

The lack of accurate information on energy expenditure and weight-related behaviors in youth with DS significantly impedes the successful prevention and treatment of obesity for this vulnerable population. The findings of this study will provide a further understanding of weight-related behaviors as obesity risk factors, currently not well understood for this population. This study will advance the science of weight management in individuals with disabilities and shift clinical practice paradigms.

Parental perception of facilitators and barriers to health among young children with down syndrome: a qualitative study

Background

Despite high rates of obesity and weight-related conditions observed in children with Down syndrome, little is known about how to prevent these conditions.

Purpose

The purpose of this study was to identify parent-perceived facilitators and barriers to health for toddlers (12-36 months old) with Down syndrome.

Materials and methods

We conducted in-depth, semi-structured interviews with the mothers of 25 toddlers with Down syndrome. All interviews were conducted using Zoom Video Technology, audio recorded and transcribed before being coded in NVivo software using a structured protocol. Thematic analysis was used to identify themes in perceived facilitators and barriers to health at the level of the child, family, and community. Data were triangulated using reflective journaling, video review of child meals, and member-checking techniques.

Results

We identified unique themes for facilitators (on the move and sound sleep) and barriers (co-occurring conditions and eating behaviors) at the level of the child. At the level of the family and community, overarching themes that were viewed as either a facilitator or barrier, depending on the context, were identified (role models matter, time is critical, the importance of place, and social support).

Conclusion

These themes can help clinicians and researchers tailor their health promotion interventions to meet the unique needs of children with Down syndrome by using strength-based approaches and providing families with the tools to overcome barriers.

Diet Quality and Cardiometabolic Risk Factors in Adolescents with Down Syndrome

BACKGROUND

Youth with Down syndrome (DS) have a high prevalence of obesity and dyslipidemia. Diet quality may influence cardiometabolic risk (CMR) in youth.

OBJECTIVE

The aim of this secondary analysis was to investigate the relationship between diet quality (Healthy Eating Index [HEI-2015]) with CMR factors in youth with DS compared with age, sex, race, ethnicity, and body mass index percentile matched, typically developing controls.

DESIGN

Adolescents (aged 10 to 20 years) with DS and controls of comparable age, sex, race, ethnicity, and body mass index percentile were recruited from 2012 to 2017 for a cross-sectional study from two large children's hospitals (Children's Hospital of Philadelphia and the Children's National Health System in Washington, DC).

PARTICIPANTS AND SETTING

CMRs in 143 adolescents with DS were compared with 100 controls. Exclusion criteria consisted of major organ-system illnesses.

MAIN OUTCOME MEASURES

The average of three 24-hour dietary recalls was used to calculate the HEI-2015. Anthropometrics, blood pressure, and fasting labs were collected.

STATISTICAL ANALYSES PERFORMED

Group differences were tested using Wilcoxon rank-sum tests. Relationships of CMR factors with HEI-2015 score within DS and controls were tested using linear regression models adjusted for sex, age, race, and body mass index z score.

RESULTS

Compared with controls (n = 100, median age = 14.8 years [interquartile range = 12.2 to 17.3 years]; 41% male; 24% African American; 65% with body mass index ≥85th percentile), adolescents with DS (n = 143, median age = 14.7 years [interquartile range = 11.4 to 17.4 years]; 44% male; 18% African American; 62% with body mass index ≥85th percentile) had higher scores (more aligned with dietary recommendations) for total HEI-2015 (DS: 52.7 [interquartile range = 46.8 to 58.6] vs controls: 45.1 [interquartile range = 39.5 to 55.0]; P < 0.0001). Youth with DS also had higher HEI-2015 component scores for fruits, greens/beans, dairy, refined grains, and saturated fats, but lower whole grains and sodium scores. Within the group with DS, total HEI-2015 was not significantly associated with CMR measures. Whereas HEI-2015 in the DS group was negatively associated with fasting glucose levels, the difference did not meet the set level of statistical significance (-0.14, 95% CI -0.29 to 0.00; P = 0.053).

CONCLUSIONS

Adolescents in both the control and DS groups reported low-quality diets, although the DS group had HEI-2015 scores more closely aligned with recommendations. In the DS group, diet quality was not significantly associated with CMR factors. Although further research is needed, these results suggest that dyslipidemia in youth with DS may not be related to dietary intake.

Resting energy expenditure in adolescents with Down syndrome: a comparison of commonly used predictive equations

BACKGROUND

Adolescents with Down syndrome (DS) are two to three times more likely to be obese than their typically developing peers. When preventing or treating obesity, it is useful for clinicians to understand an individual's energy intake needs. Predictive resting energy expenditure (REE) equations are often recommended for general use in energy intake recommendations; however, these predictive equations have not been validated in youth with DS. The aim of this study was to compare the accuracy of seven commonly used predictive equations for estimating REE in adolescents who are typically developing to REE measured by indirect calorimetry in adolescents with DS.

METHODS

Adolescents with DS participated in a 90-min laboratory visit before 10:00 a.m. after a 12-h overnight fast and a 48-h abstention from aerobic exercise. REE was measured via indirect calorimetry, and estimated REE was derived using the Institute of Medicine, Molnar, Muller and World Health Organization equations. Mean differences between the measured and predicted REE for each equation were evaluated with equivalency testing, and P-values were adjusted for multiple comparisons using the Holm method.

RESULTS

Forty-six adolescents with DS (age: 15.5 ± 1.7 years, 47.8% female, 73.9% non-Hispanic White) completed the REE assessment. Average measured REE was 1459.5 ± 267.8 kcal/day, and the Institute of Medicine equations provided the most accurate prediction of REE with a 1.7 ± 11.2% (13.9 ± 170.3 kcal/day) overestimation. This prediction was not statistically different from the measured REE [P-value = 0.582; 95% confidence interval (CI): -64.5, 36.7], and the difference between the measured and predicted REE was statistically equivalent to zero (P-value = 0.024; 90% CI: -56.1, 28.3).

CONCLUSIONS

The results suggest that the Institute of Medicine equation may be useful in predicting REE in adolescents with DS. Future research should confirm these results in a larger sample and determine the utility of the Institute of Medicine equation for energy intake recommendations during a weight management intervention.

Dysregulated systemic metabolism in a Down syndrome mouse model

OBJECTIVE

Trisomy 21 is one of the most complex genetic perturbations compatible with postnatal survival. Dosage imbalance arising from the triplication of genes on human chromosome 21 (Hsa21) affects multiple organ systems. Much of Down syndrome (DS) research, however, has focused on addressing how aneuploidy dysregulates CNS function leading to cognitive deficit. Although obesity, diabetes, and associated sequelae such as fatty liver and dyslipidemia are well documented in the DS population, only limited studies have been conducted to determine how gene dosage imbalance affects whole-body metabolism. Here, we conduct a comprehensive and systematic analysis of key metabolic parameters across different physiological states in the Ts65Dn trisomic mouse model of DS.

METHODS

Ts65Dn mice and euploid littermates were subjected to comprehensive metabolic phenotyping under basal (chow-fed) state and the pathophysiological state of obesity induced by a high-fat diet (HFD). RNA sequencing of liver, skeletal muscle, and two major fat depots were conducted to determine the impact of aneuploidy on tissue transcriptome. Pathway enrichments, gene-centrality, and key driver estimates were performed to provide insights into tissue autonomous and non-autonomous mechanisms contributing to the dysregulation of systemic metabolism.

RESULTS

Under the basal state, chow-fed Ts65Dn mice of both sexes had elevated locomotor activity and energy expenditure, reduced fasting serum cholesterol levels, and mild glucose intolerance. Sexually dimorphic deterioration in metabolic homeostasis became apparent when mice were challenged with a high-fat diet. While obese Ts65Dn mice of both sexes exhibited dyslipidemia, male mice also showed impaired systemic insulin sensitivity, reduced mitochondrial activity, and elevated fibrotic and inflammatory gene signatures in the liver and adipose tissue. Systems-level analysis highlighted conserved pathways and potential endocrine drivers of adipose-liver crosstalk that contribute to dysregulated glucose and lipid metabolism.

CONCLUSIONS

A combined alteration in the expression of trisomic and disomic genes in peripheral tissues contribute to metabolic dysregulations in Ts65Dn mice. These data lay the groundwork for understanding the impact of aneuploidy on in vivo metabolism.

Field-based versus laboratory-based estimates of muscle quality index in adolescents with and without Down syndrome

BACKGROUND

Low muscle quality index (MQI) is a potential risk of developing functional impairments in older people. However, considering that individuals with Down syndrome (DS) present with a faster decline in biological aging, an investigation on MQI in individuals with DS is necessary. The aims of this present cross-sectional study were to compare (1) MQI between adolescents with and without DS and (2) evaluate laboratory versus field-based estimates of MQI.

METHODS

Fifty-six adolescents were recruited and separated into two groups: DS (n = 30, 13 boys and 17 girls; age: 12.38 ± 3.07 years) and a control (non-DS; n = 26, 9 boys and 17 girls; age: 12.46 ± 2.88 years). Laboratory MQI was derived from the ratio of grip strength to arm muscle mass (in kg) measured by dual-energy X-ray absorptiometry (DXA). Field-based MQI was quantified from the ratio of hand grip strength (HGS) to body mass index (BMI). For statistical analyses, a two-way ANOVA was conducted for group comparisons, and a Pearson correlation was used to test the association between field MQI and laboratory MQI.

RESULTS

Adolescents with DS displayed lower field (P = 0.001), laboratory MQI estimates (P = 0.001) and HGS (P = 0.001) as compared non-DS. Also, there was a strong correlation effect between field MQI and laboratory MQI estimates (P < 0.001, R = 0.81).

CONCLUSION

Adolescents with DS have lower field and laboratory MQI compared with adolescents without DS. Simpler field MQI might be used in daily clinical practice, with special attention to those with DS.

Genetics of Obesity in Humans: A Clinical Review

Obesity is a complex multifactorial disorder with genetic and environmental factors. There is an increase in the worldwide prevalence of obesity in both developed and developing countries. The development of genome-wide association studies (GWAS) and next-generation sequencing (NGS) has increased the discovery of genetic associations and awareness of monogenic and polygenic causes of obesity. The genetics of obesity could be classified into syndromic and non-syndromic obesity. Prader–Willi, fragile X, Bardet–Biedl, Cohen, and Albright Hereditary Osteodystrophy (AHO) syndromes are examples of syndromic obesity, which are associated with developmental delay and early onset obesity. Non-syndromic obesity could be monogenic, polygenic, or chromosomal in origin. Monogenic obesity is caused by variants of single genes while polygenic obesity includes several genes with the involvement of members of gene families. New advances in genetic testing have led to the identification of obesity-related genes. Leptin (LEP), the leptin receptor (LEPR), proopiomelanocortin (POMC), prohormone convertase 1 (PCSK1), the melanocortin 4 receptor (MC4R), single-minded homolog 1 (SIM1), brain-derived neurotrophic factor (BDNF), and the neurotrophic tyrosine kinase receptor type 2 gene (NTRK2) have been reported as causative genes for obesity. NGS is now in use and emerging as a useful tool to search for candidate genes for obesity in clinical settings.

Weight management recommendations for youth with Down syndrome: Expert recommendations

Youth with Down syndrome (DS) have a higher prevalence of overweight and obesity compared to the general youth population. Due to physiological and cognitive differences observed in youth with DS, weight management recommendations developed for the general population, may not be suitable for youth with DS. However, there are no recent recommendations for weight management in youth with DS. A workgroup of clinicians and researchers with extensive experience working with youth with DS came together to give clinicians and families guidance for weight management in youth with DS. Recommendations were developed by the workgroup via a methodical, deliberative process. After the initial development of the recommendations, they were shared with an expert review panel and caregivers who rated the strength of the recommendation and strength of the evidence. The workgroup moved forward the recommendations which the review panels rated as strong. Eight recommendations were developed which focused on screening for overweight and obesity, screening for health conditions that may impact dietary intake and physical activity, screening for feeding difficulties, setting appropriate recommendations for dietary intake and physical activity, and well as prevention and treatment of overweight and obesity using evidence-based strategies. These recommendations can be implemented by clinicians working with youth with Down syndrome as well as the family, school, and other relevant entities.

Weight loss in adolescents with down syndrome compared to adolescents with other intellectual disabilities enrolled in an 18-month randomized weight management trial

BACKGROUND

There is limited information on the efficacy of weight management interventions in adolescents with Down Syndrome (DS).

OBJECTIVE

To compare weight change and intervention compliance between adolescents with DS compared to adolescents with non-DS related intellectual disabilities (ID) who were enrolled in an 18-month weight management trial.

METHODS

Participants were adolescents (13-21 years) with mild to moderate ID and overweight or obesity. Participants were randomized in a 1:1:1 allocation to one of 3 intervention arms for an 18-month weight management trial: face-to-face/conventional diet (FTF/CD), remote delivery/conventional diet (RD/CD), or remote delivery/enhanced Stop Light Diet (RD/eSLD). Anthropometrics were assessed at baseline 6, 12, and 18 months by staff blinded to the intervention, and self-monitoring data was collected across the 18-month study. As an unpowered, post-hoc, secondary analysis, two-sample t-tests were used to compare the weight change across 6,12, and 18 mos. and compliance across 18 mos. between adolescents with and without DS randomized to each intervention arm.

RESULTS

Adolescents with ID (n = 110) were randomized to one of three intervention arms: FTF/CD (n = 36, DS = 17, other ID = 19), RD/CD (n = 39, DS = 21, other ID = 18) or RD/eSLD (n = 35, DS = 15, other ID = 20). Body weight at 18 months was obtained from 82%, 76% and 73% of participants with DS and 84%, 83% and 75% of participants with other ID randomized to the FTF/CD, RD/CD, and RD/eSLD arms, respectively Weight change across 18 months was -0.2 ± 8.8 kg (-0.5%), -0.3 ± 5.3 kg (-0.7%), and -2.6 ± 5.0 kg (-4.0%) in adolescents with DS randomized to the FTF/CD, RD/CD and RD/eSLD arms, respectively. There were no significant differences in change in body weight or BMI across 18 months between adolescents with DS or those with other ID in any of the 3 intervention arms (all p > 0.05). Additionally, there were no significant differences in intervention compliance between adolescents with and without DS across 18 mos. (all p > 0.05).

CONCLUSIONS

Adolescents with DS respond to a multi-component weight management intervention similar to those with others ID.

Trisomy 21 and Coronavirus Disease 2019 in Pediatric Patients

We present 4 pediatric patients with trisomy 21 (T21) and associated comorbidities who developed coronavirus disease 2019 requiring hospitalization. A review of the literature revealed that comorbidities associated with T21 may predispose patients to severe disease. Children with T21 should be considered high risk and monitored carefully if infected with severe acute respiratory syndrome coronavirus 2.

Meta-analysis of metabolites involved in bioenergetic pathways reveals a pseudohypoxic state in Down syndrome

Clinical observations and preclinical studies both suggest that Down syndrome (DS) may be associated with significant metabolic and bioenergetic alterations. However, the relevant scientific literature has not yet been systematically reviewed. The aim of the current study was to conduct a meta-analysis of metabolites involved in bioenergetics pathways in DS to conclusively determine the difference between DS and control subjects. We discuss these findings and their potential relevance in the context of pathogenesis and experimental therapy of DS. Articles published before July 1, 2020, were identified by using the search terms “Down syndrome” and “metabolite name” or “trisomy 21” and “metabolite name”. Moreover, DS-related metabolomics studies and bioenergetics literature were also reviewed. 41 published reports and associated databases were identified, from which the descriptive information and the relevant metabolomic parameters were extracted and analyzed. Mixed effect model revealed the following changes in DS: significantly decreased ATP, CoQ10, homocysteine, serine, arginine and tyrosine; slightly decreased ADP; significantly increased uric acid, succinate, lactate and cysteine; slightly increased phosphate, pyruvate and citrate. However, the concentrations of AMP, 2,3-diphosphoglycerate, glucose, and glutamine were comparable in the DS vs. control populations. We conclude that cells of subjects with DS are in a pseudo-hypoxic state: the cellular metabolic and bio-energetic mechanisms exhibit pathophysiological alterations that resemble the cellular responses associated with hypoxia, even though the supply of the cells with oxygen is not disrupted. This fundamental alteration may be, at least in part, responsible for a variety of functional deficits associated with DS, including reduced exercise difference, impaired neurocognitive status and neurodegeneration.

Systematic review of sedentary behaviour in people with Down syndrome across the lifespan: A clarion call

BACKGROUND

Individuals with Down syndrome (DS) experience health disparities possibly associated with high levels of sedentary behaviour (SB). We systematically reviewed SB measurement, levels, patterns, correlates, consequences and interventions in people with DS across the lifespan.

METHOD

We searched these databases: Embase; PubMed; Web of Science; Scopus; CINAHL; PsycINFO; SPORTDiscus; and Cochrane Library. We included quantitative studies published in English since 1 January 1990.

RESULTS

We identified 17 eligible articles. Across studies, accelerometer-determined sedentary time was 552 min/day (median: 542; range 392-680 min/day). Sedentary time appeared higher than previously reported values in the general population, especially for youth with DS. Multivariate SB correlates were primarily familial and environmental. Sedentary behaviour consequences have not been exclusively studied. Motor skills training reduced SB in youth with DS.

CONCLUSIONS

Sedentary behaviour research in this population is in early stages. Individuals with DS have high levels of SB that may be responsive to interventions.

Does Tonsillectomy Increase Obesity Risk in Children with Down Syndrome?

OBJECTIVES

To examine weight changes relative to surgical success in children with Down syndrome and obstructive sleep apnea (OSA).

STUDY DESIGN

Retrospective chart review of children with Down syndrome undergoing tonsillectomy from 2005 to 2016 for OSA at a tertiary care children's hospital. Only patients with pre-and postoperative polysomnogram within 6 months of tonsillectomy were included. Demographics, weight, height, and polysomnogram data were collected. Body mass index (BMI), expressed as a percentage of the 95th percentile (%BMI_p95), was calculated for 24 months prior to and following surgery. Pre-and postoperative OSA severity were also recorded. The postoperative obstructive/hypopnea index identified subjects with resolution of obstruction (obstructive/hypopnea index <2 events/hour) or persistent mild/moderate/severe obstructive apnea. Regression analyses were used to compare %BMI_p95 pre- and post-tonsillectomy with %BMI_p95 by OSA status following tonsillectomy.

RESULTS

A total of 78 patients with Down syndrome whose mean age was 5.29 years at time of tonsillectomy were identified. There was no difference between best-fit curves of %BMI _p95 pre-and post-tonsillectomy. There was no difference between best-fit curves of %BMI _p95 in patients who saw resolution of OSA after tonsillectomy vs patients with residual OSA.

CONCLUSIONS

Tonsillectomy neither alters the BMI trajectory of children with Down syndrome, nor changes differentially the risk for obesity in children whose OSA did or did not resolve after surgery.

Cardiometabolic Risk and Body Composition in Youth With Down Syndrome

BACKGROUND AND OBJECTIVES

Whether BMI captures adiposity and cardiometabolic risk in Down syndrome (DS), a condition associated with obesity, short stature, and altered body proportions, is not known. We compared cardiometabolic risk measures in youth with DS and typically developing matched controls.

METHODS

Youth with (n = 150) and without (n = 103) DS of comparable age (10-20 years), sex, race, ethnicity, and BMI percentile underwent whole-body dual-energy X-ray absorptiometry, fasting glucose, insulin, lipids, lipoprotein particles, inflammatory factors, and when BMI percentile ≥85, an oral glucose tolerance test.

RESULTS

Sixty-four percent of youth with DS had BMI percentile ≥85. Among these, no difference in glucose, insulin, or insulin resistance was detected, but prediabetes was more prevalent with DS (26.4% vs 10.3%; P = .025) after adjustment for demographics, pubertal status, and BMI z score (odds ratio = 3.2; P = .026). Among all participants, those with DS had higher low-density lipoprotein cholesterol (median 107 [interquartile range 89-128] vs 88.5 [79-103] mg/dL; P < .00005), triglycerides (89.5 [73-133] vs 71.5 [56-104] mg/dL; P < .00005), non-high-density lipoprotein cholesterol (non-HDL-C; 128 [104-153] vs 107 [92-123] mg/dL; P < .00005), and triglycerides/HDL-C (2.2 [1.6-3.4] vs 1.7 [1.1-2.5] mg/dL; P = .0003) and lower levels of HDL-C (41 [36.5-47] vs 45 [37-53] mg/dL; P = .012). DS youth had higher high-sensitivity C-reactive protein, interleukin-6, small low-density lipoprotein particles (LDL-P), and total LDL-P, but similar LDL-P size. Youth with DS had less visceral fat (VFAT), fat mass, and lean mass for BMI z score, but greater VFAT at higher fat mass. However, VFAT did not fully explain the increased prevalence of dyslipidemia or prediabetes in youth with DS.

CONCLUSIONS

Despite similar insulin resistance, youth with DS had greater prevalence of dyslipidemia and prediabetes than typically developing youth, which was not fully explained by VFAT.

Pediatric endocrinology through syndromes

In everyday practice, a pediatric endocrinologist will face a variety of different endocrine issues (such as short or tall stature, dysthyroidism, abnormal pubertal timing or impaired glucose metabolism), which relevantly contribute to the global care of a number of syndromic conditions. On the other hand, the presence of endocrine features may assist in the diagnostic process, leading to final diagnosis of a syndromic disorder. The intention of this review is to provide a referenced overview of different genetic syndromes characterized by endocrine features, and to present a possible classification, based on whether the endocrinopathy or the syndrome is typically recognized first. Thus, the first part of the manuscript deals with the most common syndromes associated with endocrine dysfunctions, while the second part describes the conditions by which a syndrome is most frequently diagnosed after an endocrine finding. The aim is to provide a practical overview of the assessment of syndromic patients, so that they can be recognized and managed in an integrated, multidisciplinary fashion.

Regulator of Calcineurin 1 helps coordinate whole-body metabolism and thermogenesis

Increasing non-shivering thermogenesis (NST), which expends calories as heat rather than storing them as fat, is championed as an effective way to combat obesity and metabolic disease. Innate mechanisms constraining the capacity for NST present a fundamental limitation to this approach, yet are not well understood. Here, we provide evidence that Regulator of Calcineurin 1 (RCAN1), a feedback inhibitor of the calcium-activated protein phosphatase calcineurin (CN), acts to suppress two distinctly different mechanisms of non-shivering thermogenesis (NST): one involving the activation of UCP1 expression in white adipose tissue, the other mediated by sarcolipin (SLN) in skeletal muscle. UCP1 generates heat at the expense of reducing ATP production, whereas SLN increases ATP consumption to generate heat. Gene expression profiles demonstrate a high correlation between Rcan1 expression and metabolic syndrome. On an evolutionary timescale, in the context of limited food resources, systemic suppression of prolonged NST by RCAN1 might have been beneficial; however, in the face of caloric abundance, RCAN1-mediated suppression of these adaptive avenues of energy expenditure may now contribute to the growing epidemic of obesity.

Occurrence of Hypothyroidism, Diabetes Mellitus, and Celiac Disease in Emirati Children with Down's Syndrome

Objectives

Autoimmune diseases are known to occur in people with Down's syndrome (DS), especially celiac disease, type 1 diabetes mellitus (DM), and hypothyroidism. Since there are common genetic risk factors involved in the occurrence of these autoimmune disorders, the risks would differ in different populations. We sought to determine the prevalence of type 1 DM, celiac disease, and hypothyroidism in Emirati patients with DS in Abu Dhabi, UAE.

Methods

Ninety-two patients with DS were investigated for the presence of anti-thyroid antibodies, antithyroglobulin, and anti-thyroid peroxidase antibodies for hypothyroidism, anti-glutamic acid decarboxylase antibodies for type 1 DM, and anti-tissue transglutaminase immunoglobulin A antibodies for celiac disease.

Results

Karyotyping was performed on 89 patients. Eighty-seven had non-disjunction of chromosome 21 (97.8%), one was a mosaic, and one had translocation. Of the patients studied, 19.6% had hypothyroidism, 4.3% had type 1 DM, and 1.1% had celiac disease. Out of the 92 patients studied, 66 (71.7%) did not have any autoimmune disease, 25 (27.2%) had one autoimmune disease, and one (1.1%) had two autoimmune diseases.

Conclusions

Celiac disease was the least prevalent autoimmune disease in patients with DS patients, while type 1 DM and hypothyroidism were both significantly associated with DS.

Dietary practices of children and adolescents with Down syndrome

The aim of this study was to assess dietary intake, breastfeeding history, weight at birth and current weight in children and adolescents with Down syndrome (DS). Therefore, a cross-sectional, controlled study with 19 DS participants and 19 controls without DS matched by gender and age was performed. Except for vitamin D, a lower or the same frequency of insufficient intake in other micronutrients was noted in participants compared with controls. The DS group had a reduced exclusive breastfeeding duration and increased carbohydrate and caloric intake. The consumption of micronutrients in both groups reinforced the current trend of excessive sodium consumption and insufficient intake of calcium, some B complex vitamins and water by children and adolescents.

Increased levels of inflammatory plasma markers and obesity risk in a mouse model of Down syndrome

Down syndrome (DS) is caused by the trisomy of human chromosome 21 and is the most common genetic cause of intellectual disability. In addition to the intellectual deficiencies and physical anomalies, DS individuals present a higher prevalence of obesity and subsequent metabolic disorders than healthy adults. There is increasing evidence from both clinical and experimental studies indicating the association of visceral obesity with a pro-inflammatory status and recent studies have reported that obese people with DS suffer from low-grade systemic inflammation. However, the link between adiposity and inflammation has not been explored in DS. Here we used Ts65Dn mice, a validated DS mouse model, for the study of obesity-related inflammatory markers. Ts65Dn mice presented increased energy intake, and a positive energy balance leading to increased adiposity (fat mass per body weight), but did not show overweight, which only was apparent upon high fat diet induced obesity. Trisomic mice also had fasting hyperglycemia and hypoinsulinemia, and normal incretin levels. Those trisomy-associated changes were accompanied by reduced ghrelin plasma levels and slightly but not significantly increased leptin levels. Upon a glucose load, Ts65Dn mice showed normal increase of incretins accompanied by over-responses of leptin and resistin, while maintaining the hyperglycemic and hypoinsulinemic phenotype. These changes in the adipoinsular axis were accompanied by increased plasma levels of inflammatory biomarkers previously correlated with obesity galectin-3 and HSP72, and reduced IL-6. Taken together, these results suggest that increased adiposity, and pro-inflammatory adipokines leading to low-grade inflammation are important players in the propensity to obesity in DS. We conclude that DS would be a case of impaired metabolic-inflammatory axis.

The role of physical activity in improving physical fitness in children with intellectual and developmental disabilities

BACKGROUND

One in three children in North America are considered overweight or obese. Children with intellectual and developmental disabilities (IDD) are at an increased risk for obesity than their typically developing peers. Decreased physical activity (PA) and low physical fitness may be contributing factors to this rise in obesity.

AIM

Because children with IDD are at an increased risk of diseases related to inactivity, it is important to improve health-related physical fitness to complete activities of daily living and improve health.

METHODS AND PROCEDURES

The focus of this research is on improving the performance of physical fitness components through physical activity programming among a group of children with IDD, ages 7-12 years. The Brockport Physical Fitness Test was used assess levels of physical fitness of 35 children with IDD (25 boys, 10 girls) before and after participation in a 10-week program.

OUTCOMES AND RESULTS

The results of paired sampled t-tests showed participation in 15-h PA program can significantly increase aerobic capacity and muscular strength and endurance in children with IDD.

CONCLUSIONS AND IMPLICATIONS

This study is aimed at understanding the role of PA in helping children with IDD to develop the fitness capacities essential to participation in a wide variety of activities.

Bone health in Down syndrome

Patients with Down syndrome have a number of risk factors that theoretically could predispose them to osteoporosis, such as early aging, development disorders, reduced physical activity, limited sun exposure, frequent comorbidities and use of drug therapies which could affect bone metabolism. In addition, the bone mass of these people may be affected by their anthropometric and body composition peculiarities. In general terms, studies in adults with Down syndrome reported that these people have lower areal bone mineral density (g/cm²) than the general population. However, most of them have not taken the smaller bone size of people with Down syndrome into account. In fact, when body mineral density is adjusted by bone size and we obtain volumetric body mineral density (g/cm³), the difference between both populations disappears. On the other hand, although people with Down syndrome have risk factor of hypovitaminosis D, the results of studies regarding 25(OH)D in this population are not clear. Likewise, the studies about biochemical bone markers or the prevalence of fractures are not conclusive.

Body mass index reference charts for individuals with Down syndrome aged 2-18 years

OBJECTIVE

To develop Brazilian growth charts for body mass index (BMI-for-age) for individuals with Down syndrome (DS). The secondary objective was to compare the BMI-for-age with the Centers for Disease Control and Prevention standards (CDC).

METHODS

A retrospective and cross-sectional growth study of 706 youth with DS (56.7% males) was performed in 51 centers in São Paulo state, Brazil. Weight and height were used to calculate the BMI (kg/m²). The LMS method was applied to construct the growth charts. Z-scores were based on the CDC 2000 growth standards.

RESULTS

The BMI-for-age reference charts showed excellent goodness of fit statistics for boys and girls with DS aged 2-18 years. At 2 years of age, the mean BMI Z-scores of boys and girls with DS were lower compared to those of the CDC (Z-score=-0.2). In contrast, children with DS aged 3-18 years had higher mean Z-scores for BMI-for-age when compared to those of the CDC (Z-scores=+0.2 to +1.3).

CONCLUSIONS

The BMI of Brazilian youth with DS differs from those references established by CDC. These are the first Brazilian BMI-for-age charts for individuals with DS and will hopefully guide clinicians and parents in the evaluation and management of the nutritional status in children and adolescents with DS in Brazil.

Overweight and obesity in children and adolescents with Down syndrome-prevalence, determinants, consequences, and interventions: A literature review

BACKGROUND

Children with Down syndrome (DS) are more likely to be overweight or obese than the general population of youth without DS.

AIMS

To review the prevalence of overweight and obesity and their determinants in youth with DS. The health consequences and the effectiveness of interventions were also examined.

METHODS AND PROCEDURES

A search using MEDLINE, Embase, Web of Science, Scopus, CINAHL, PsycINFO, SPORTDiscus, LILACS, and COCHRANE was conducted. From a total of 4280 studies, we included 45 original research articles published between 1988 and 2015.

OUTCOMES AND RESULTS

The combined prevalence of overweight and obesity varied between studies from 23% to 70%. Youth with DS had higher rates of overweight and obesity than youths without DS. Likely determinants of obesity included increased leptin, decreased resting energy expenditure, comorbidities, unfavorable diet, and low physical activity levels. Obesity was positively associated with obstructive sleep apnea, dyslipidemia, hyperinsulinemia, and gait disorder. Interventions for obesity prevention and control were primarily based on exercise-based programs, and were insufficient to achieve weight or fat loss.

CONCLUSIONS AND IMPLICATIONS

Population-based research is needed to identify risk factors and support multi-factorial strategies for reducing overweight and obesity in children and adolescents with DS.

Percentage of body fat in adolescents with Down syndrome: Estimation from skinfolds

BACKGROUND

Adolescents with Down syndrome (DS) have a unique morphology and body shape, and this needs to be taken into account when assessing body fat percentage (BF%).

OBJECTIVE

To develop a predictive equation from anthropometric variables (skinfolds) for estimating BF% in adolescents with DS.

METHODS

Twenty-three adolescents with DS (7 girls, 16 boys) participated in the study; seven skinfold measurements were taken (biceps, triceps, subscapular, supraspinale, abdominal, front thigh, and medial calf), circumferences and diameters were measured following ISAK recommendations. Total body volume (and then body density) was measured with air displacement plethysmography (ADP); BF% was then calculated. Correlation between anthropometry data and BF% by ADP, and stepwise regression analyses were applied to develop a specific prediction equation.

RESULTS

All the skinfolds, BMI, hip, waist and thigh circumferences correlated with BF% and were included in the regression analysis; sex and triceps were added into the model (R² = 0.89, p < 0.05). Therefore the proposed equation computed as follows: BF% = (0.97 TR) - (8.869·SEX) + 15.6 where TR is triceps skinfolds (mm) and SEX is equal to 0 for female and 1 for male.

CONCLUSIONS

The proposed prediction equation is recommended for the assessment of BF% in adolescents with DS as it is the only one specifically developed and validated in this unique population. It is a cheap, reliable and accessible method that removes the need for use of expensive equipment.

Retrospective Study of Obesity in Children with Down Syndrome

OBJECTIVES

To assess whether children with Down syndrome in the US are at an increased risk for obesity, we determined the obesity prevalence and analyzed obesity development throughout childhood in a cohort of children with Down syndrome. In addition, we analyzed a comorbidity that is associated with Down syndrome and obesity, obstructive sleep apnea syndrome (OSAS).

STUDY DESIGN

This study was a retrospective chart review that evaluated 303 children ages 2 through 18 years with a diagnosis of Down syndrome. All children were patients at Cincinnati Children's Hospital Medical Center with multiple height and weight measurements. To determine obesity burden, the rate of obesity was compared with a local control cohort using contingency tables. Change in obesity rate through time was determined with mixed models. Association of obesity with OSAS was determined with contingency tables.

RESULTS

We evaluated 303 individuals, 47.8% of whom were obese (body mass index ≥95th percentile for age and sex). This was significantly higher than the general pediatric population, which had a 12.1% obesity rate (P < .0001). Body mass index z-scores did not change markedly over time (P = .40). The majority of children with Down syndrome also had OSAS (74.0% of the 177 children who had polysomnography studies). However, OSAS risk was elevated in obese children (risk ratio = 2.4, P = .0015).

CONCLUSIONS

Our results indicate that children with Down syndrome are at a substantial risk for obesity and OSAS. These findings support the need for more aggressive weight management in early childhood and throughout the lifespan.

Body composition estimation using skinfolds in children with and without health conditions affecting growth and body composition

BACKGROUND

Body composition prediction equations using skinfolds are useful alternatives to advanced techniques, but their utility across diverse paediatric populations is unknown.

AIM

To evaluate published and new prediction equations across diverse samples of children with health conditions affecting growth and body composition.

SUBJECTS AND METHODS

Anthropometric and dual-energy X-ray absorptiometry (DXA) body composition measures were obtained in children with Down syndrome (n = 59), Crohn disease (n = 128), steroid-sensitive nephrotic syndrome (n = 67) and a healthy reference group (n = 835). Published body composition equations were evaluated. New equations were developed for ages 3-21 years using the healthy reference sample and validated in other groups and national survey data.

RESULTS

Fat mass (FM), fat-free mass (FFM) and percentage body fat (%BF) from published equations were highly correlated with DXA-derived measures (r = 0.71-0.98), but with poor agreement (mean difference = 2.4 kg, -1.9 kg and 6.3% for FM, FFM and %BF). New equations produced similar correlations (r = 0.85-1.0) with improved agreement for the reference group (0.2 kg, 0.4 kg and 0.0% for FM, FFM and %BF, respectively) and in sub-groups.

CONCLUSIONS

New body composition prediction equations show excellent agreement with DXA and improve body composition estimation in healthy children and those with selected conditions affecting growth.

Supporting a happy, healthy adolescence for young people with Down syndrome and other intellectual disabilities: recommendations for clinicians

PURPOSE OF REVIEW

To review clinical updates and current healthcare issues for adolescents with Down syndrome and intellectual disabilities, including behavioral, social, and emotional issues, health supervision recommendations, and recommendations for supporting the transition process.

RECENT FINDINGS

Several recent findings merit particular attention: low activity levels and implications for overweight and poor bone density; high prevalence of obstructive sleep apnea and its implications; prevalence of mental health and behavioral concerns; and need for appropriate transition services.

SUMMARY

In guiding adolescents with Down syndrome towards healthy productive adult lives, clinicians can make use of healthcare guidelines and should also take a broader, more interdisciplinary approach to ensure that social, educational, and vocational plans are in place to support physical and mental health and development during transition into adulthood. Many of these issues have broader applicability to any adolescent with an intellectual disability.

Obesity Prevention for Children with Developmental Disabilities

The prevention of obesity in children with DD is a pressing public health issue, with implications for health status, independent living, and quality of life. Substantial evidence suggests that children with developmental disabilities (DD), including those with intellectual disabilities (ID) and autism spectrum disorder (ASD), have a prevalence of obesity at least as high if not higher than their typically developing peers. The paper reviews what is known about the classic and unique risk factors for childhood obesity in these groups of children, including dietary, physical activity, sedentary behavior, and family factors, as well as medication use. We use evidence from the literature to make the case that primary prevention at the individual/family, school and community levels will require tailoring of strategies and adapting existing intervention approaches.