The body mass index (BMI) is a simple and widely utilized screening tool for obesity in children and adults. The purpose of this investigation was to evaluate if BMI could predict total fat mass ...(TFM) and percent body fat (%FAT) in a sample of overweight and obese children.
In this observational study, body composition was measured by dual energy x-ray absorptiometry (DXA) in 663 male and female overweight and obese children at baseline within a multidisciplinary, pediatric fitness clinic at an academic medical center. Univariate and multivariate regression analyses were conducted to evaluate whether BMI z-score (BMIz) predicts TFM or %FAT.
The BMIz, sex and age of subjects were identified as significant predictors for both TFM and %FAT. In subjects younger than 9 years, the BMIz was a weak to moderate predictor for both TFM (R
= 0.03 for males and 0.26 for females) and %FAT (R
= 0.22 for males and 0.38 for females). For subjects between 9 and 18 years, the BMIz was a strong predictor for TFM (R
between 0.57 and 0.73) while BMIz remained only moderately predictive for %FAT (R
between 0.22 and 0.42).
These findings advance the understanding of the utility and limitations of BMI in children and adolescents. In youth (9-18y), BMIz is a strong predictor for TFM, but a weaker predictor of relative body fat (%FAT). In children younger than 9y, BMIz is only a weak to moderate predictor for both TFM and %FAT. This study cautions the use of BMIz as a predictor of %FAT in children younger than 9 years.
The age and sex standardized body mass index (BMIz) is a simple and widely utilized screening tool for obesity in children and adolescents. The purpose of this study was to evaluate the relationship ...between the BMIz trajectory versus the percent body fat (%FAT) trajectory, and if BMIz could predict significant changes in %FAT in a sample of obese children and adolescents.
In this longitudinal observational study, body composition was measured by dual energy x-ray absorptiometry (DXA) in obese children within a multidisciplinary pediatric fitness clinic at an academic medical center over a 3-year time period. Regression analyses were conducted to evaluate the association between changes in BMIz and changes in %FAT.
Baseline assessment was obtained from 515 participants. The reduction observed in BMIz (2.20 to 2.08, p < 0.0001) correlated with the reduction in %FAT (38.5 to 35.8%, p < 0.05) in the first two years. The overall correlation between the slope in BMIz reduction versus %FAT reduction was moderate (r = 0.36, p < 0.0001) over the 3-year follow-up period. The sensitivity of BMIz changes for predicting a decrease in %FAT was acceptable (70, 95% CI: 61-78%), however the specificity was poor (42, 95% CI: 31-54%).
These findings advance the understanding of the utility and limitations of BMIz in children and adolescents. While BMIz may be sensitive to changes in adiposity, it is a weak predictor of these changes in total body fat (%FAT) due to the poor specificity. Therefore, clinicians must exercise caution when monitoring changes in a growing child's body composition to avoid misclassifying or missing substantial change when utilizing BMIz alone.
Rett syndrome (RTT) is a neurodevelopmental autism spectrum disorder that affects girls due primarily to mutations in the gene encoding methyl-CpG binding protein 2 (MECP2). The majority of RTT ...patients carry missense and nonsense mutations leading to a hypomorphic MECP2, while null mutations leading to the complete absence of a functional protein are rare. MECP2 is an X-linked gene subject to random X-chromosome inactivation resulting in mosaic expression of mutant MECP2. The lack of human brain tissue motivates the need for alternative human cellular models to study RTT. Here we report the characterization of a MECP2 mutation in a classic female RTT patient involving rearrangements that remove exons 3 and 4 creating a functionally null mutation. To generate human neuron models of RTT, we isolated human induced pluripotent stem (hiPS) cells from RTT patient fibroblasts. RTT-hiPS cells retained the MECP2 mutation, are pluripotent and fully reprogrammed, and retained an inactive X-chromosome in a nonrandom pattern. Taking advantage of the latter characteristic, we obtained a pair of isogenic wild-type and mutant MECP2 expressing RTT-hiPS cell lines that retained this MECP2 expression pattern upon differentiation into neurons. Phenotypic analysis of mutant RTT-hiPS cell-derived neurons demonstrated a reduction in soma size compared with the isogenic control RTT-hiPS cell-derived neurons from the same RTT patient. Analysis of isogenic control and mutant hiPS cell-derived neurons represents a promising source for understanding the pathogenesis of RTT and the role of MECP2 in human neurons.
BMIz-score (BMIz) is commonly used to assess childhood obesity. Whether change in BMIz score predicts change in visceral fat remains unclear. The objective of the work was to study changes in ...visceral fat, cardiovascular fitness (CVF), and metabolic health over 6 months in children with stable/decreased-BMIz vs. increased-BMIz. Ninety children with obesity, referred for lifestyle intervention were studied (mean age 11±3.1 years, 50% girls, 22% Hispanic). Assessment included abdominal and total fat by dual X-ray absorptiometry (DXA), sub-maximal VO
for CVF, anthropometrics, and fasting insulin, glucose, HDL-C, triglycerides, AST and ALT at 0 and 6 months. Sixty-three children (70%) showed a stable/decrease in BMIz over 6 months. There was no significant change in total body fat between groups (-1.3±2.9% in BMIz-stable/down vs. - 0.6 ± 2.6% BMIz-up, p=0.459); however, BMIz-stable/down group showed a decrease in visceral fat compared to the BMIz-up group (-258±650 g vs.+137±528 g, p=0.009). BMIz-stable/down group also demonstrated increased CVF (+1.2 ml/kg/min, p<0.001), not seen in the BMIz-up group. Neither group had significant changes in metabolic markers. Preventing BMIz increase in obese children predicts a significant decrease in visceral fat even if total body fat is unchanged. This is often associated with increased fitness. Thus, increasing fitness level and keeping BMI stable are strategic initial goals for obese children.
Background Childhood obesity remains a public health concern, and tracking local progress may require local surveillance systems. Electronic health record data may provide a cost-effective solution. ...Purpose To demonstrate the feasibility of estimating childhood obesity rates using de-identified electronic health records for the purpose of public health surveillance and health promotion. Methods Data were extracted from the Public Health Information Exchange (PHINEX) database. PHINEX contains de-identified electronic health records from patients primarily in south central Wisconsin. Data on children and adolescents (aged 2–19 years, 2011–2012, n =93,130) were transformed in a two-step procedure that adjusted for missing data and weighted for a national population distribution. Weighted and adjusted obesity rates were compared to the 2011–2012 National Health and Nutrition Examination Survey (NHANES). Data were analyzed in 2014. Results The weighted and adjusted obesity rate was 16.1% (95% CI=15.8, 16.4). Non-Hispanic white children and adolescents (11.8%, 95% CI=11.5, 12.1) had lower obesity rates compared to non-Hispanic black (22.0%, 95% CI=20.7, 23.2) and Hispanic (23.8%, 95% CI=22.4, 25.1) patients. Overall, electronic health record–derived point estimates were comparable to NHANES, revealing disparities from preschool onward. Conclusions Electronic health records that are weighted and adjusted to account for intrinsic bias may create an opportunity for comparing regional disparities with precision. In PHINEX patients, childhood obesity disparities were measurable from a young age, highlighting the need for early intervention for at-risk children. The electronic health record is a cost-effective, promising tool for local obesity prevention efforts.
Background: Children with Prader-Willi syndrome (PWS) have decreased muscle mass, hypotonia, and impaired linear growth. Recombinant human GH (hGH) treatment reportedly improves body composition and ...physical function in children with PWS, but these studies lack long-term control data. To assess the impact of hGH therapy begun early in life on the natural history of PWS, we compared height, body composition, and strength in similar-age children with PWS naïve to hGH with those treated with hGH for 6 yr.
Objectives: Forty-eight children with PWS were studied: 21 subjects (aged 6–9 yr) treated with hGH for 6 yr (beginning at 4–32 months, mean 13 ± 6 months) were compared with 27 children of similar age (5–9 yr) prior to treatment with hGH. Percent body fat, lean body mass, carbohydrate/lipid metabolism, and motor strength were compared using analysis of covariance.
Results: PWS children treated with hGH demonstrated lower body fat (mean, 36.1 ± 2.1 vs. 44.6 ± 1.8%, P < 0.01), greater height (131 ± 2 vs. 114 ± 2 cm; P < 0.001), greater motor strength increased standing broad jump 22.9 ± 2.1 vs. 14.6 ± 1.9 in. (P < 0.001) and sit-ups 12.4 ± 0.9 vs. 7.1 ± 0.7 in 30 sec (P < 0.001), increased high-density lipoprotein cholesterol (58.9 ± 2.6 vs. 44.9 ± 2.3 mg/dl, P < 0.001), decreased low-density lipoprotein (100 ± 8 vs. 131 ± 7 mg/dl, P < 0.01), and no difference in fasting glucose or insulin.
Conclusions: hGH treatment in children with PWS, begun prior to 2 yr of age, improves body composition, motor function, height, and lipid profiles. The magnitude of these effects suggests that long-term hGH therapy favorably alters the natural history of PWS to an extent that exceeds risks and justifies consideration for initiation during infancy.
Long-term GH therapy alters the natural history of Prader-Willi syndrome to an extent that compares favorably with possible risks.
Outpatient management of pediatric obesity can be difficult, requiring a significant time commitment from both provider and patient. Multidisciplinary clinic-based programs have shown promising ...effects in reducing BMI during intervention, but whether these changes are sustained over time is not well studied. The purpose of this study was to determine the post-treatment outcomes of children seen in a multidisciplinary pediatric obesity clinic (MPOC).
A retrospective chart review was performed using the MPOC database, which included all clinic patients from January 2008 to August 2016 who attended a minimum of 2 visits (n = 472). The primary outcome was the absolute change in BMI Z-score (BMIZ) from the final intervention visit compared to 1- and 2-years post-intervention. Multivariate regression analysis was performed to characterize predictors of change in BMIZ.
MPOC patients ranged in age from 3 to 18 years. Mean BMIZ decreased significantly during intervention (-0.13 ± 1.47, P < .001) and was maintained at 1- and 2-years post-intervention. In participants ages 3 to 5, BMIZ further decreased at 1 year post intervention (-0.27 ± 0.26, P < .001). Age at time of referral was the only significant predictor of change in BMIZ.
Outpatient, multidisciplinary intervention for pediatric obesity was effective in reducing or stabilizing BMIZ during and beyond the intervention, particularly when patients were referred at an early age. Although primary prevention is the ideal management, multidisciplinary clinic intervention can be effective in the sustained treatment of pediatric obesity.
INTRODUCTIONRecent studies report a significant impact of the COVID-19 pandemic on the incidence, severity, and management of diabetes. OBJECTIVETo determine the incidence of new onset pediatric ...diabetes prepandemic versus during the pandemic and to analyze the presentation based on age, severity, HbA1c, body mass index, and COVID testing. METHODSWe conducted a retrospective review of all pediatric patients admitted with newly diagnosed type 1 and type 2 diabetes mellitus admitted to the American Family Children's Hospital (Madison, Wisconsin) from 2018 through 2021. Data included age at diagnosis, body mass index, hemoglobin A1c percent and pH at presentation, presence of autoimmune pancreatic antibodies, and COVID-19 polymerase chain reaction (PCR) results at admission in pre-COVID (January 2018-February 2020) versus during COVID (March 2020-December 2021). Statistical analysis was performed using SAS software with the incidences analyzed using univariate and multivariate Poisson regression analyses. RESULTSDuring the pandemic, the incidence of both type 1 and type 2 diabetes mellitus increased significantly (69% and 225%, P < 0.001, respectively), and a higher number of patients had diabetic ketoacidosis. Type 1 diabetes patients with a body mass index greater than the 95th percentile increased from 11.1% to 16.9% (OR 0.62; 95% CI, 0.29-1.29; P = 0.19). Almost all patients were COVID-19 PCR negative at the time of diagnosis. CONCLUSIONSA dramatic increase in number and severity of newly diagnosed pediatric diabetes cases was seen during the pandemic. The increase was not explained by factors such as changes in referral patterns or insurance coverage. Further work is needed to understand the impact of societal factors and the direct diabetogenic effect of SARS-CoV-2.
Childhood obesity and associated comorbidities, including insulin resistance, are increasing in the United States. Our objectives were to (1) determine the prevalence of insulin resistance in ...children seen in dyslipidemia clinic and (2) evaluate which aspects of the lipid profile correlate with insulin resistance.
Children and adolescents seen in a specialized pediatric dyslipidemia clinic without secondary diagnoses known to alter the lipid panel were included. Simultaneous fasting lipid panel, insulin, and glucose levels were available in 572 children (50.5% male).
Mean patient age was 15.0±3.6 years with the majority being over 10 years of age (92.5%). Mean BMI was 29.8±8.1 kg/m
and BMI standard deviation score was 1.80±0.9. Mean HOMA-IR was 6.2±5.7 with a range of 0.4-49.3, and interquartile range of 2.7-7.6. Triglyceride level had a positive correlation with HOMA-IR (p<0.001). HDL-C negatively correlated with HOMA-IR even controlling for triglyceride level by multivariate analysis (p=0.001) and HDL-C <30 mg/dL predicted IR with 41.5% PPV.
In children and adolescents with dyslipidemia, insulin resistance is common and significantly correlates with reduced HDL-C levels. Non-fasting samples are easier to obtain in children and low HDL-C, which is minimally affected on non-fasting samples, could be an easily obtained indicator of IR. Increasing detection of insulin resistance in children with dyslipidemia may provide greater opportunities for lifestyle interventions and possible pharmacotherapy to modify cardiovascular risk.
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