MULT: A new BMI reference to assess nutritional status of multi‐ethnic children and adolescents

Abstract

ObjectivesTo develop a new Body Mass Index (BMI) reference (MULT) based on longitudinal data of multi‐ethnic populations and to compare it to international BMI references.MethodsThe MULT BMI reference was constructed through the LMS method and the Generalized Additive Models for Location Scale and Shape (GAMLSS), with 81 310 observations of 17 505 subjects aged 0–22 years old, from the United Kingdom, Ethiopia, Peru, India, Vietnam, Brazil, and Portugal. Outlier values were removed based on weight z‐scores (population level) and based on BMI z‐scores using the linear mixed effects model (individual level). The MULT M, S and L curves were compared to the ones of the World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF), and Dutch Growth Study (DUTCH). The MULT BMI percentile cutoffs for overweight and obesity were calculated using the adult BMI values of 25 and 30 kg/m2 at 17, 18, 19, and 20 years old.ResultsMULT presented the lowest mean BMI values for the ages 102–240 months for boys and 114–220 months for girls. MULT S values were similar to the WHO and IOTF for children under 60 months of age and the highest during puberty, while the L curve showed to be more symmetric than the other BMI references.ConclusionThe MULT BMI reference was constructed based on recent data of populations from 10 countries, being a good option to assess the nutritional status of multi‐ethnic populations.

Comparison of international height and BMI-for-age growth references and their correlation with adiposity in Brazilian schoolchildren

“…This study provided valuable insights into the correlation, diagnostic accuracy and concordance of different growth references based on body adiposity indicators. High positive correlations were identified among BMI z-scores and skinfold measurements, particularly with the MULT reference (14) displaying robust associations. The diagnostic accuracy assessment revealed nuanced patterns, with the IOTF and MULT (17 years) obesity percentiles exhibiting trade-offs between sensitivity and specificity (14,17,18) .…”

“…The diagnostic accuracy, which includes sensitivity, specificity, positive likelihood ratio (þLR) and negative likelihood ratio (−LR) of the BMI references, was performed based on the classification of high adiposity values obtained from the sum of skinfold measurements (29) . Additionally, since the MULT BMI reference presented four different cut-off options for obesity, the analyses were performed for all cut-off options, showing the one more adequate to be applied to Brazilian children and adolescents (14) .…”

“…The prevalence of normal height and stunting was estimated using the WHO and MULT height references (13,16) . Additionally, the prevalence of underweight, normal weight, overweight and obesity was calculated according to the BMI reference values of the WHO, IOTF and MULT (14,(16)(17)(18) . For the MULT BMI reference (14) , the following cut-off points were applied for both sexes: (a) underweight for percentile < 3rd; (b) overweight for percentile ≥ 85 th and (c) obesity for percentile ≥ 98th.…”

“…The height-for-age growth chart shows the linear growth trajectory, which is essential for detecting stunting, while the BMI-for-age growth chart identifies underweight, overweight and obesity conditions (10,12) . There are international growth references recommended to be applied worldwide, and the most recent published was the MULT growth reference (2023), which was constructed with data from multi-ethnic children and adolescents from ten countries (13,14) . Other growth references, such as the ones from the World Health Organization (WHO, 2006/2007), the International Task Obesity Force (IOTF/ 2012) and the Centers for Disease Control and Prevention (CDC, 2000) have been used internationally over the years (15)(16)(17)(18)(19) .…”

“…Moreover, they have been essential for assessing nutritional status at the population level, although there is no consensus on which one is the most appropriate for international use, especially in children over five years old (10,11) . Therefore, this study aimed to compare the nutritional status classified by the WHO (2007) (16) , IOTF (2012) (18) and MULT (2023) (13,14) height and BMI references and verify their diagnostic accuracy in detecting obesity based on body adiposity in Brazilian schoolchildren.…”