The growth of youth with Down syndrome (DS) differs from that of youth without DS, and growth charts specific to DS have been developed. However, little is known about the growth of Brazilian youth with DS. The objective of this study was to construct growth charts for Brazilian youth with DS and compare the growth data with the Child Growth Standards of the World Health Organization (WHO) and charts for children with DS from other studies. Mixed longitudinal and cross-sectional data were collected at University of Campinas, 48 specialized centers for people with intellectual disabilities, and two foundations for people with DS between 2012 and 2015. A total of 10,516 growth measurements from birth to 20 years of age were available from 938 youth with DS (53.7% boys) born between 1980 and 2013. The Lambda Mu Sigma method was applied to construct the curves using generalized additive models for location, scale, and shape. Length/height-for-age, weight-for-age, and head circumference-for-age percentile curves were generated for Brazilian boys and girls from birth to 20 years of age. Differences in growth of Brazilian youth ranged from -0.8 to -3.2 z-scores compared to WHO standards, and -1.9 to +1.3 compared to children with DS in other studies. These specific growth charts may guide clinicians and families in monitoring the growth of Brazilian children and adolescents with DS.

Objective: Population-level monitoring of body composition requires accurate, biologically-relevant, yet feasible methods for estimating percent body fat (%BF). The aim of this study was to develop and cross-validate an equation for %BF from Body Mass Index (BMI), age, and sex among children with intellectual disability (ID). This study further aimed to examine the performance of an existing BMI-based equation (Deurenberg equation) for %BF in children with ID. Method: Participants were 107 children (63 boys; aged 6-15 years) with ID randomly allocated to development (n = 81) and cross-validation (n = 26) samples. Dual-Energy X-Ray Absorptiometry provided the criterion %BF. Results: The model including BMI, age, and sex (0 = male; 1 = female) had a significant goodness-of-fit in determining %BF (p < 0.001; R-2 = 0.69; SEE =5.68%). The equation was: %BF = - 15.416 + (1.394 x BMI) + (4.538 x age) - (0.262 x age(2)) + (5.489 x sex). The equation was cross-validated in the separate sample based on (i) strong correlation (r = 0.82; p < 0.001) and non-significant differences between actual and predicted %BF (28.6 +/- 9.6% and 30.1 +/- 7.1%, respectively); (ii) mean absolute error (MAE) = 4.4%; and (iii) reasonable %BF estimations in Bland-Altman plot (mean: 1.48%; 95% CI: 12.5, -9.6). The Deurenberg equation had a large %BF underestimation (mean: -7.1%; 95% CI: 5.3, -19.5), significant difference between actual and estimated %BF (28.6 +/- 9.7% and 21.5 +/- 7.0%, respectively; p < 0.001), and MAE = 8.1%. Conclusions: The developed equation with BMI, sex, and age provides valid %BF estimates for facilitating population-level body fat screening among children with ID. (C) 2022 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda.

To develop growth charts for weight-for-age, height-for-age, and body mass index (BMI)-for-age for both genders aged 2 to 18 years for Brazilian patients with Williams-Beuren Syndrome (WBS). This is a multicenter, retrospective, and longitudinal study, data were collected from the medical records of boys and girls with a confirmed diagnosis of WBS in three large university centers in the state of Sao Paulo, Brazil. Growth charts stratified by gender and age in years were developed using LMSchartmaker Pro software. The LMS (Lambda Mu Sigma) method was used to model the charts . The quality of the settings was checked by worm plots. The first Brazilian growth charts for weight-for-age, height-for-age, and BMI-for-age stratified by gender were constructed for WBS patients aged 2 to 18 years. The growth charts developed in this study can help to guide family members and to improve the health care offered by health professionals.

Youth with intellectual disabilities (IDs) demonstrate below-criteria motor competence (MC) compared with typically developing (TD) youth. Whether differences in MC exist for youth with ID from different countries is unknown. This study examined the MC of youth with ID from Brazil (BR) and the United States (US) and compared it with norms for TD youth as established by the Bruininks–Oseretsky Test of Motor Proficiency (BOT-2). The authors measured 19 BOT-2 test items for bilateral coordination, balance, and upper limb coordination of 502 youth (BR = 252, US = 250) with ID (6–21 years). Raw scores were converted to %ceiling (percentile of highest expected scores). For all test items, no significant differences were seen between BR and US participants in %ceiling scores. Participants from both countries demonstrated equivalent to slightly below BOT-2 norms in 14 of the 19 test items, with lowest scores seen in contralateral synchronizing bilateral coordination, balancing on one leg, and ball handling.