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

This study verified the diagnostic accuracy of the nutritional status classified by the international height and BMI references of the World Health Organization (WHO) (WHO/2007), International Obesity Task Force (IOTF/2012) and MULT (2023). The data pool was composed by 22 737 subjects aged five to 16 years from the Santos and Porto Alegre surveys. A correlation matrix between the z-scores of the BMI references and the skinfold measurements was calculated through the Pearson correlation coefficient (r), and the subject's nutritional status was classified according to the international growth references. The accuracy for diagnosing obesity was performed separately by sex and using the 95th percentile of the triceps and subscapular skinfold sum, while Lin's concordance coefficient, Bland-Altman method and the Cohen's Kappa coefficient (Kappa) were used to verify the concordance and reliability among the BMI references. The correlation matrix showed a high positive correlation among the BMI z-scores (r ≥ 0·99) and among the skinfold measurements (r ≥ 0·86). The prevalence of stunting was higher when applying the MULT reference (3·4 %) compared with the WHO reference (2·3 %). The Bland-Altman plots showed the lowest critical difference (CD) between the height references of WHO and MULT (CD = 0·22). Among the BMI references, the WHO obesity percentile presented lower performance than MULT for boys, presenting a lower +LR value (WHO = 6·99/MULT 18 years = 10·99; 19 years = 8·99; 20 years = 8·09) for the same -LR values (0·04). Therefore, MULT reference holds promise as a valuable tool for diagnosing childhood obesity, particularly when considering sex differences. This enhances its suitability for assessing the nutritional status of Brazilian schoolchildren.

Risk assessment of obesity-related noncommunicable diseases through body mass index trajectories in adulthood: NHANES 2007-2018.

AIM: To assess the impact of adult body mass index (BMI) trajectories on the risk of obesity-related noncommunicable diseases (NCDs) in the U.S. adults after adjustment for sociodemographic and lifestyle factors. METHODS: Data were extracted from the National Health and Nutrition Examination Survey conducted from 2007 to 2018, including male and female participants aged 29-59 years. Rao-Scott adjusted chi-square was employed to detect associations between categorical variables in descriptive analyses. Cox proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for NCDs and BMI trajectories, adjusted for sociodemographic and lifestyle factors. Kaplan-Meier curves illustrated the cumulative incidence over time. RESULTS: Analyses were carried out on 15 721 participants and revealing significant differences among BMI trajectories in terms of demographic, lifestyle, and health characteristics. The overall prevalence of NCDs was 28.0% (95%CI:26.6-28.9). The cumulative incidence over time was higher in the high increase, moderate increase, and mixed trajectory groups, with a correspondingly higher cumulative risk (p < 0.001). Non-overweight trajectory was considered reference category in Cox models. The BMI trajectories were independently associated with an increased risk of NCDs, even after adjusting for potential confounders (HR: 1.7; 95%CI: 1.4-1.9 for moderate increase; HR: 3.6; 95%CI: 3.2-4.1 for high increase; and HR: 2.4; 95%CI: 2.1-2.7, for mixed). Furthermore, differences between males and females were also observed. CONCLUSION: The transition to and persistence of obesity into adulthood increases the risk of NCDs. The implementation of targeted interventions with long-term monitoring of BMI may be beneficial in the prevention of future obesity-related NCDs.

Frequency of anthropometric implausible values estimated from different methodologies: a systematic review and meta-analysis.

CONTEXT: Poor anthropometric data quality affect the prevalence of malnutrition and could harm public policy planning. OBJECTIVE: This systematic review and meta-analysis was designed to identify different methods to evaluate and clean anthropometric data, and to calculate the frequency of implausible values for weight and height obtained from these methodologies. DATA SOURCES: Studies about anthropometric data quality and/or anthropometric data cleaning were searched for in the MEDLINE, LILACS, SciELO, Embase, Scopus, Web of Science, and Google Scholar databases in October 2020 and updated in January 2023. In addition, references of included studies were searched for the identification of potentially eligible studies. DATA EXTRACTION: Paired researchers selected studies, extracted data, and critically appraised the selected publications. DATA ANALYSIS: Meta-analysis of the frequency of implausible values and 95% confidence interval (CI) was estimated. Heterogeneity (I2) and publication bias were examined by meta-regression and funnel plot, respectively. RESULTS: In the qualitative synthesis, 123 reports from 104 studies were included, and in the quantitative synthesis, 23 studies of weight and 14 studies of height were included. The study reports were published between 1980 and 2022. The frequency of implausible values for weight was 0.55% (95%CI, 0.29-0.91) and for height was 1.20% (95%CI, 0.44-2.33). Heterogeneity was not affected by the methodological quality score of the studies and publication bias was discarded. CONCLUSIONS: Height had twice the frequency of implausible values compared with weight. Using a set of indicators of quality to evaluate anthropometric data is better than using indicators singly. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42020208977.

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

OBJECTIVES: To 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. METHODS: The 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. RESULTS: MULT 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. CONCLUSION: The 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.

MULT: New height references and their efficiency in multi-ethnic populations.

OBJECTIVES: To develop new height references (MULT) based on longitudinal data of multi-ethnic populations and to compare them to the height references from the Dutch Growth Study, from the Centers for Disease Control and Prevention (CDC) and from the World Health Organization (WHO). METHODS: The MUL height references were developed through the LMS method and the Generalized Additive Models for Location Scale and Shape. They were constructed based on 2611 subjects (15 292 measurements) from the advantaged quintile of the Young Lives (Younger Cohort), Millennium Cohort Study, Adolescent Nutritional Assessment Longitudinal Study, and Epidemiological Health Investigation of Teenagers in Porto studies. The M, S curves were described to compare the growth trajectory of the MULT, DUTCH, CDC and WHO height references. For the population comparative analysis, we used the total sample of the studies (91 063 observations, 17 641 subjects). The Lin's concordance correlation coefficient (CCC) and Cohen's kappa coefficient (K) were used to verify the agreement between MULT, WHO and CDC height references. RESULTS: The MULT height references showed taller boys for the periods of 61-174 months and 196-240 months and taller girls for 61-147 and 181-240 months, when compared to CDC and WHO height references. There was an almost perfect agreement between WHO and MULT height references (CCC >0.99) for the subjects aged 2 to 5 years. CONCLUSIONS: MULT height references presented a taller population and a high agreement with WHO growth charts, especially for children under 5 years, indicating that it could be useful to assess nutritional status of multi-ethnic populations.

Body phenotypes and sexual maturation in Brazilian and US adolescents: evidence for a change in BMI category.

OBJECTIVE: Our study aimed to describe body phenotypes (BP) estimated by multivariate analysis and their association with body mass. DESIGN: BP were defined based on demographic variables, anthropometric data (body mass, height, skinfolds and circumferences), body composition (phase angle measured by bioelectrical impedance analysis), biochemical parameters (TAG, glucose, total cholesterol ratio/LDL, Hb and sexual maturation (pubic hair and breasts or gonads). ANOVA was performed to verify the differences between skin colour and the stages of pubertal development, BP, body composition, anthropometric and biochemical variables. SETTING: Cities of São Paulo-SP, Piracicaba-SP and Florianópolis-SC from Brazil and the United States. PARTICIPANTS: 9269 adolescents aged between 10 and 15 years old. RESULTS: The composition of BP was similar in all surveys, which are: BP1 was composed by skinfolds, body mass and circumferences variables; BP2 by pubic hair, breast in girls or gonad in boys, height and age; BP3 by cholesterol, TAG and glucose; and BP4 by phase angle, Hb and glucose (negative loading). There was a strong correlation (r = 0·9, P < 0·001) between BP1 and BMI. CONCLUSION: We highlighted independence observed between biochemical parameters, anthropometry, body composition and sexual maturation. BP may support the calculation of scores for diagnosis of obesity based on anthropometric variables and overcome ambiguity in the isolated use of BMI.