Body Mass Index Z-score Trajectories Research Articles

Prospective associations between neighborhood features and body mass index in Montreal adolescents.

PurposeTo investigate the association between the neighborhood built environment and trajectories of body mass index (BMI) in youth. MethodsData were collected in a prospective study of 1293 adolescents in Montreal. Built environment variables were obtained from public databases for road networks, land use, and the Canadian Census. Anthropometric data were collected when participants were ages 12.5, 15 and 17 years. We undertook hierarchical cluster analysis to identify contrasting neighborhood types based on features of the built environment (e.g., vegetation, population density, walkability). Associations between neighborhood type and trajectories of BMI z-score (BMIz) were estimated using multivariable linear mixed regression analyses, stratified by sex. ResultsWe identified three neighborhood types: Urban, Suburban, and Village. In contrast to the Urban type, the Suburban type was characterized by more vegetation, few services and low population density. Village and Suburban types were similar, but the former had greater land use diversity, population density with more parks and a denser food environment. Among girls, living in Urban types was associated with decreasing BMIz trajectories. Living in Village types was associated with increasing BMIz trajectories. No associations were observed among boys. ConclusionsNeighborhoods characterized by greater opportunities for active living appear to be less obesogenic, particularly among girls.

Environmental Phenols and Growth in Infancy: The Infant Feeding and Early Development Study.

Higher mean and rapid increases in body mass index (BMI) during infancy are associated with subsequent obesity and may be influenced by exposure to endocrine-disrupting chemicals such as phenols. In a prospective US-based cohort conducted 2010-2014, we investigated associations between environmental phenol exposures and BMI in 199 infants. We measured seven urinary phenols at ages 6-8 and 12 weeks and assessed BMI z-score at up to 12 study visits between birth and 36 weeks. We examined individual and joint associations of averaged early infancy phenols with level of BMI z-score using mean differences (β [95% confidence intervals (CI)]) and with BMI z-score trajectories using relative risk ratios (RR [95% CI]). Benzophenone-3, methyl and propyl paraben, and all phenols jointly were positively associated with higher mean BMI z-score (0.07 [-0.05, 0.18], 0.10 [-0.08, 0.27], 0.08 [-0.09, 0.25], 0.17 [-0.08, 0.43], respectively). Relative to a Stable trajectory, benzophenone-3, 2,4-dichlorophenol, 2,5-dichlorophenol, and all phenols jointly were positively associated with risk of a Rapid Increase trajectory (1.46 [0.89, 2.39], 1.33 [0.88, 2.01], 1.66 [1.03, 2.68], 1.41 [0.71, 2.84], respectively). Early phenol exposure was associated with a higher mean and rapid increase in BMI z-score across infancy, signaling potential long-term cardiometabolic consequences of exposure.

PM2.5 constituents associated with childhood obesity and larger BMI growth trajectory: A 14-year longitudinal study

BackgroundThe association of specific PM2.5 chemical constituents with childhood overweight or obesity (OWOB) remain unclear. Furthermore, the long-term impacts of PM2.5 exposure on the trajectory of children's body mass index (BMI) have not been explored. MethodsWe conducted a longitudinal study among 1,450,830 Chinese children aged 6–19 years from Beijing and Zhongshan in China during 2005–2018 to examine the associations of PM2.5 and its chemical constituents with incident OWOB risk. We extracted PM2.5 mass and five main component exposure from Tracking Air Pollution in China (TAP) dataset. Cox proportional hazards models were applied to quantify exposure–response associations. We further performed principal component analysis (PCA) to handle the multi-collinearity and used quantile g-computation (QGC) approach to analyze the impacts of exposure mixtures. Additionally, we selected 125,863 children with at least 8 physical examination measurements and combined group-based trajectory models (GBTM) with multinomial logistic regression models to explore the impacts of exposure to PM2.5 mass and five constituents on BMI and BMI Z-score trajectories during 6–19 years. ResultsWe observed each interquartile range increment in PM2.5 exposure was significantly associated with a 5.1 % increase in the risk of incident OWOB (95 % confidence Interval [CI]: 1.036–1.066). We also found black carbon, sulfate, organic matter, often linked to fossil combustion, had comparable or larger estimates of the effect (HR = 1.139–1.153) than PM2.5. Furthermore, Exposure to PM2.5 mass, sulfate, nitrate, ammonium, organic matter and black carbon was significantly associated with an increased odds of being in a larger BMI trajectory and being assigned to persistent OWOB trajectory. ConclusionsOur findings provide evidence that the constituents mainly from fossil fuel combustion may have a perceptible influence on increased OWOB risk associated with PM2.5 exposure in China. Moreover, long-term exposure to PM2.5 contributes to an increased odds of being in a lager BMI and a persistent OWOB trajectories.

SAT348 Changes In BMI Z-score After Presentation For Early Breast Budding Is Associated With Rapidly Progressive Puberty And Treatment With GnRH Analogues

Abstract Disclosure: H. Jung: None. J. Cho: None. K. Shim: None. Introduction: Childhood overweight and obesity are associated with earlier pubertal timing, especially in girls. We aimed to identify different body mass index (BMI) trajectories in patients presenting for breast budding between 5 and 7 years of age, and investigated whether the change in BMI z-scores during follow up is associated with rapid progression of puberty and eventual treatment with gonadotropin-releasing hormone (GnRH) analogues. Methods: We retrospectively reviewed girls who presented with breast budding at 5 to 7 years of age, between March 2016 and May 2021 at a single center. Those 206 girls, who had more than 3 follow up BMI measurements to more than 9 years of age were included in the study. The girls were grouped according to whether BMI z-scores increased or decreased/remain unchanged overall during follow-up. The BMI z-score changes over time (age) were also assessed for latent class trajectories. The risk of progression to rapid progressive puberty requiring treatment with GnRH analogues was analyzed according to overall changes in BMI z-scores and the different BMI trajectory groups, with adjustment for birthweight, gestational age, maternal menarche, maternal height, as well as the initial age, height, and bone age at presentation. Results: The mean age at presentation for breast budding was 7.1±0.7 years. A greater proportion of girls whose BMI z-scores increased during follow up, required treatment with GnRH analogues (n=53, 64%) compared to those whose BMI z-scores decreased or remained unchanged (n=54, 44%). Girls with increases in BMI z-scores during follow up (n=83) had increased risk (OR 4.68, 95% CI 1.88-11.63, p = 0.001) for rapid progressive puberty and treatment with GnRH analogues compared to those girls with decreases/no changes (n=123) in BMI z-scores, even after adjustment for covariates. Further analysis showed that increases in BMI z-scores even in those of normal weight status, were associated with increased OR (4.88) for treatment. Through latent class mixed modelling analysis, we identified 2 different trajectories (high and increasing BMI z-scores, n=72; and decreasing BMI z-scores, n=134). Risk for rapid progression of puberty and eventual treatment with GnRH analogues did not differ significantly between the different latent class trajectories. Conclusions: Increases in BMI z-scores during the follow up period after presentation for early breast budding may be associated with increased risk for rapid progression of puberty and treatment with GnRH analogues. Analysis of a larger group of patients may allow for better assessment of latent class BMI z-score trajectories. Presentation: Saturday, June 17, 2023

In utero exposure to perfluoroalkyl substances and early childhood BMI trajectories: A mediation analysis with neonatal metabolic profiles

BackgroundIn utero perfluoroalkyl substances (PFAS) exposure has been associated with childhood adiposity, but the mechanisms are poorly known. ObjectiveTo investigate the potential mediating role of neonatal metabolites in the relationship between prenatal PFAS exposure and childhood adiposity trajectories in the first four years of life. MethodsWe analyzed the data for 1671 mother-child pairs from the Shanghai Birth Cohort study. We included those with PFAS exposure information in early pregnancy, neonatal metabolites data and at least three child anthropometric measurements at 6, 12, 24 and/or 48 months. Body mass index (BMI) z-score trajectories were identified using latent class growth mixture modeling. The associations between PFAS concentrations and trajectory classes were assessed using multinomial logistic regression. Screening and penalization-based selection was used to identify neonatal amino acids and acylcarnitines with significant mediation effects. ResultsThree BMI z-score trajectories in early childhood were identified: a persistent increase trajectory (Class 1, 2.2 %), a stable trajectory (Class 2, 66 %), and a transient increase trajectory (Class 3, 32 %). Increased odds of being in Class 1 were observed in association with one log-unit increase in concentrations of perfluorooctane sulfonate (odds ratio [OR], 1.76 [95 % CI, 0.96–3.23], Class 2 as reference; OR, 2.36 [95 % CI, 1.27–4.40], Class 3 as reference), perfluorononanoic acid (OR, 1.90 [95 % CI, 0.97–3.72], Class 2 as reference; OR, 2.23 [95 % CI, 1.12–4.42], Class 3 as reference) and perfluorodecanoic acid (OR, 1.95 [95 % CI, 1.12–3.38], Class 2 as reference; OR, 2.14 [95 % CI, 1.22–3.76], Class 3 as reference). The effect of prenatal PFAS exposure on being in Class 1 was significantly but partly mediated by octanoylcarnitine (2.64 % for perfluorononanoic acid and 3.70 % for sum of 10 PFAS). ConclusionsIn utero PFAS exposure is a risk factor for persistent growth in BMI z-score in early childhood. The alteration of neonatal acylcarnitines suggests a potential molecular pathway.

Fetal exposure to cannabis, neonatal adiposity, and postnatal growth trajectories: The Healthy Start study

Objective: Cannabis use during pregnancy is associated with lower birth weight and may influence postnatal growth. We estimated associations of fetal exposure to cannabis with neonatal adiposity and body mass index (BMI) z-score trajectories through age 3 years, as well as effect modification by breastfeeding. Methods: We leveraged a subsample of 130 mother-child pairs from a Colorado-based cohort. Twelve cannabinoids/metabolites (including delta 9-tetrahydrocannabinol [THC] and cannabidiol [CBD]) were measured in maternal urine collected at ~27 weeks gestation. Fetal exposure to cannabis was dichotomized as exposed (any cannabinoid≥limit of quantification) and not exposed (cannabinoids<limit of quantification). Generalized linear models estimated the associations between fetal exposure to cannabis with birth weight and neonatal adiposity (measured by air displacement plethysmography). A mixed-effects model estimated the association between fetal cannabis exposure and BMI z-score trajectories. Interaction by breastfeeding duration was assessed by including a product term (with fetal exposure to cannabis) in a mixed-effects model. Results: Fetal exposure to cannabis was associated with lower birth weight (-206g; 95% CI: -393, -18; p=0.03) and neonatal adiposity (-2.0%; 95% CI: -3.7, -0.02; p=0.03) followed by rapid postnatal growth through 3 years (0.37 increase in BMI z-score per square root year; 95% CI: 0.01, 0.60; p=0.02). Breastfeeding modified this association (p for interaction<0.01). Among cannabis-exposed offspring who were not breastfed, BMI z-scores were 0.42 lower at 6 months (95% CI: -1.15, 0.31) but 0.54 higher at 36 months (95% CI: -0.36, 1.44). Conversely, BMI z-scores were no different by fetal cannabis exposure among offspring who were breastfed for ~5 months. Conclusions: Our data suggests that fetal exposure to cannabis alters fetal and postnatal growth, and that breastfeeding may stabilize over-compensatory growth among cannabis-exposed offspring. Although the impact of lactational exposure to cannabis requires further investigation, it remains important to caution against cannabis use during pregnancy and lactation.

Longitudinal characterization of determinants associated with obesogenic growth patterns in early childhood.

Longitudinal assessment of the determinants of obesogenic growth trajectories in childhood can suggest appropriate developmental windows for intervention. Latent class growth mixture modelling was used to identify body mass index (BMI) z-score trajectories from birth to age 6 years in 994 children from a prospective mother-offspring cohort (Chinese, Indian and Malay ethnicities) based in Singapore. We evaluated the early-life determinants of the trajectories as well as their associations with cardiometabolic risk markers at age 6 years. Five BMI z-score trajectory patterns were identified, three within the healthy weight range, alongside early-acceleration and late-acceleration obesogenic trajectories. The early-acceleration pattern was characterized by elevated fetal abdominal circumference growth velocity, BMI acceleration immediately after birth and crossing of the obesity threshold by age 2 years. The late-acceleration pattern had normal fetal growth and BMI acceleration after infancy, and approached the obesity threshold by age 6 years. Abdominal fat, liver fat, insulin resistance and odds of pre-hypertension/hypertension were elevated in both groups. Indian ethnicity, high pre-pregnancy BMI, high polygenic risk scores for obesity and shorter breastfeeding duration were common risk factors for both groups. Malay ethnicity and low maternal educational attainment were uniquely associated with early BMI acceleration, whereas nulliparity and obesogenic eating behaviours in early childhood were uniquely associated with late BMI acceleration. BMI acceleration starting immediately after birth or after infancy were both linked to early cardiometabolic alterations. The determinants of these trajectories may be useful for developing early risk stratification and intervention approaches to counteract metabolic adversities linked to childhood obesity.

Associations of maternal non-nutritive sweetener intake during pregnancy with offspring body mass index and body fat from birth to adolescence.

The evidence that maternal non-nutritive sweetener (NNS) intake during pregnancy increases childhood obesity risk is conflicting. A potential reason for this is that all prior studies examined childhood body mass index (BMI) at only one timepoint and at different ages. We examined the extent to which NNS intake during pregnancy is associated with offspring BMI z-score and body fat longitudinally from birth to 18 years. A total of 1683 children from Project Viva, a prospective pre-birth cohort, were recruited from 1999 to 2002 in Massachusetts. We assessed maternal NNS intake in the first and second trimesters of pregnancy using a semiquantitative food frequency questionnaire. Our outcomes were offspring BMI z-score, (at birth, infancy (median 6.3 months), early childhood (3.2 years), mid-childhood (7.7 years), and early adolescence (12.9 years)), sum of skinfolds (SS), fat mass index (FMI) measured by dual x-ray absorptiometry, and BMI z-score trajectory from birth to 18 years. We adjusted models for maternal pre-pregnancy BMI, age, race/ethnicity, education, parity, pre-pregnancy physical activity, smoking, and paternal BMI and education. A total of 70% of mothers were white and pre-pregnancy BMI was 24.6 ± 5.2 kg/m2. The highest quartile of NNS intake (Q4: 0.98 ± 0.91 servings/day) was associated with higher BMI z-score in infancy (β 0.20 units; 95% CI 0.02, 0.38), early childhood (0.21; 0.05, 0.37), mid-childhood (0.21; 0.02, 0.40), and early adolescence (0.14; -0.07, 0.35) compared with Q1 intake (Q1: 0.00 ± 0.00 servings/day). Q4 was also associated with higher SS in early childhood (1.17 mm; 0.47, 1.88), mid-childhood (2.33 mm; 0.80, 3.87), and early adolescence (2.27 mm; -0.06, 4.60) and higher FMI in mid-childhood (0.26 kg/m2; -0.07, 0.59). Associations of maternal NNS intake with offspring BMI z-score became stronger with increasing age from 3 to 18 years (Pinteraction < 0.0001). Maternal NNS intake during pregnancy is associated with increased childhood BMI z-score and body fat from birth to teenage years. This is relevant given the escalating obesity epidemic, and popularity of NNS.

Prenatal exposure to PM2.5 constituents and children’s growth trajectory in the first two years: a birth cohort study

BACKGROUND AND AIM: Limited studies on the associations of prenatal exposure to fine particulate matters (PM2.5) with children’s growth reported inconsistent results. No study evaluated the effects of specific constituents of PM2.5 on children’s growth trajectory, which may contribute to discrepancies among PM2.5 studies. We aimed to examine the association of prenatal exposure to PM2.5 constituents and children’s growth trajectory in the first two years. METHODS: The study was based on a birth cohort(2014-2017) in China, involving 18,667 mothers with their children who were followed to two years old. We estimated prenatal PM2.5 constituents [organic carbon(OC), elemental carbon(EC), sulfate(SO42-), nitrate(NO3-), and ammonium (NH4+)] concentrations based on maternal home addresses. Height(or length) and weight of children were repeatedly measured at the age of 3,6,9,12,18,24 months. We calculated body mass index (BMI) Z-score based on the WHO Standards. Latent class growth modeling was used to identify children’s BMI Z-score trajectory. Multinomial logistic regression was used to examine the association of prenatal exposure to PM2.5 constituents with children’s growth trajectories. RESULTS:Three BMI Z-score trajectories were identified: stable trajectory (n=15265,81.9%), decreased trajectory(n=2130,11.4%), and increased trajectory(n=1234,6.6%). Compared with stable trajectory, an interquartile range (IQR) increase in prenatal exposure to PM2.5, NH4+, and NO3- was associated with 0.847[95% confidence interval(95%CI):0.744,0.965], 0.806(95%CI:0.710,0.915), and 0.677(95%CI: 0.603,0.761) lower risk of increased trajectory, respectively. An IQR increase in prenatal exposure to OC and SO42- was associated with 1.395(95%CI:1.236,1.575) and 1.562 (95%CI:1.324,1.842) higher risk of increased trajectory, respectively. The results were robust in two-pollutant models. We did not observe significant associations between prenatal exposure to PM2.5 constituents and risk of decreased trajectory. CONCLUSIONS:The study suggested that prenatal exposure to PM2.5 and its constituents was associated with risk of children’s increased growth trajectory in the first two years. Public health policy on regulation of harmful PM2.5 constituents should be developed to protect early-life health of children. KEYWORDS: particulate matters, constituents, body mass index, growth trajectory, children

Infant feeding and growth trajectories in early childhood: the application and comparison of two longitudinal modelling approaches.

The role of infant feeding practices in longitudinal growth trajectories in children remains equivocal. This study utilised two longitudinal approaches to examine the associations of infant feeding mode (breastfeeding, mixed feeding, formula feeding), breastfeeding duration, and the timing of solid foods introduction with body mass index (BMI) z-score in early childhood. Secondary analyses of data from the Healthy Beginnings Trial were conducted. Infant feeding practices were reported by mothers at 6, 12, and 24 months of child age. Child weight and length were measured at birth, 12, 24, 42, and 60 months. Two longitudinal approaches: linear spline multilevel model (LSMM) and group-based trajectory modelling (GBTM) were used to describe BMI z-score trajectories and assess its associations with infant feeding practices. The LSMM approach demonstrated that the breastfeeding group showed lower BMI z-scores from ages 12 to 60 months than the mixed feeding and formula feeding groups. Children who were breastfed for ≥ 6 versus < 6 months exhibited a lower BMI z-score trajectory from ages 12 to 60 months. Results from the GBTM approach revealed that the mixed feeding (OR: 1.83, 95%CI 1.04, 3.21) and the formula feeding group (OR: 2.00, 95%CI 0.67, 5.92) showed a tendency for higher odds of following the "High BMIz" trajectory than the breastfeeding group. Breastfeeding duration ≥6 versus < 6 months was linked with lower odds of following the "High BMIz" trajectory (OR 0.65, 95%CI 0.43, 0.98). Both approaches revealed no evidence of an association between the timing of solid foods introduction and BMI z-score trajectory. The two longitudinal approaches revealed similar findings that infant feeding mode and breastfeeding duration, but not the timing of solid foods introduction, were associated with BMI z-score trajectory in early childhood. The findings provide robust longitudinal evidence to encourage and support extended breastfeeding for childhood obesity prevention.

Associations Between Delivery Mode and Early Childhood Body Mass Index Z-Score Trajectories: A Retrospective Analysis of 2,685 Children From Mothers Aged 18 to 35 Years at Delivery

Objective: To investigate the association between cesarean delivery (CD) and trajectory patterns of age- and sex-specific body mass index (BMI) z-score in early childhood.Methods: A retrospective cohort study was conducted among 2,685 children whose maternal age at the time of birth was between 18 and 35 years, and birth data and anthropometric measurement data during their ages 3–60 months were collected. A group-based trajectory modeling approach was used to identify distinct BMI z-score trajectories, and multinomial logistic regressions were applied to estimate the associations among CD (both elective and non-elective combined), elective and non-selective CD, and BMI z-score trajectory classes.Results: Of the 2,685 participants, 46.5% (N = 1,248) were born by vaginal delivery (VD), 20.7% (N = 556) by elective CD, and 32.8% (N = 881) by non-elective CD. Five BMI z-score trajectory patterns were identified, and they were “increasing from moderate to high” (10.1%, n = 270), “increasing from mild to moderate” (34.2%, n = 919), “increasing from low to high” (10.5%, n = 283), “stable mild” (30.1%, n = 808), and “stable low” (15.1%, n = 405) groups. Compared with children delivered by VD, those who delivered by CD (both elective and non-elective combined), elective CD, and non-elective CD were associated with the “increasing from moderate to high” trajectory [odds ratio (OR) = 1.61, 95% confidence interval (CI): 1.13–2.29; OR = 1.64, 95%CI: 1.06–2.54; and OR = 1.59, 95%CI: 1.05–2.39, respectively] and were also associated with the “increasing from low to high” trajectory (OR = 1.60, 95%CI: 1.17–2.19, OR = 1.75, 95%CI: 1.16–2.63; and OR = 1.53, 95%CI: 1.00–2.34, respectively).Conclusion: Both elective and non-elective CD were associated with the risk of accelerated weight gain in early childhood.

The impact of change in neighborhood poverty on BMI trajectory of 37,544 New York City youth: a longitudinal study

BackgroundNeighborhood poverty may increase childhood obesity risk. However, evidence for the neighborhood poverty-obesity relationship is limited. The purpose of this study was to examine how moving to a higher or lower poverty neighborhood impacts body mass index (BMI) z-score trajectories among youth, with the goal of informing policy change, interventions, and clinical practices to reduce childhood obesity.MethodsMethods entailed secondary analysis of existing longitudinal data. The sample included youth attending New York City public schools in grades kindergarten through twelfth from school years 2006/2007 through 2016/2017. Eligibility criteria included moving to a higher or lower poverty neighborhood during the data midpoint [school years 2010/2011 through 2013/2014] of the 12-year data-period; New York City-specific metrics were used to define both neighborhood (Neighborhood Tabulation Area) and relevant neighborhood poverty levels (< 5, 5 to < 10%, 10 to < 20%, 20 to < 30%, 30 to < 40% and ≥ 40% of individuals below Federal Poverty Level). Two-piece latent growth curve models were used to describe BMI z-score trajectories of youth who moved to higher versus lower poverty neighborhoods, with propensity score weighting to account for preexisting differences between the two groups. Primary analyses were stratified by sex and exploratory subgroup analyses were stratified by sex and developmental stage (early childhood, middle childhood, and adolescence) to explore sensitive periods for neighborhood poverty exposure.ResultsOf 532,513 youth with home address data, 18,370 youth moved to a higher poverty neighborhood and 19,174 moved to a lower poverty neighborhood (n = 37,544). Females and males who moved to a higher poverty neighborhood experienced less favorable BMI z-score trajectories for obesity risk, though effects were small. Exploratory subgroup analyses demonstrated that negative effects of neighborhood poverty were most pronounced among young and adolescent females and young males, whereas effects were mixed for other subgroups.ConclusionsYouth who moved to higher poverty neighborhoods experienced less favorable BMI z-score trajectories for obesity risk, though effects were small and most consistent for females and younger youth. Additional research is needed to illuminate neighborhood poverty’s impact on obesity, in order to inform policy, intervention, clinical, and research efforts to reduce obesity and improve child well-being.

Rapid Weight Gain, Infant Feeding Practices, and Subsequent Body Mass Index Trajectories: The CALINA Study.

We aimed to study growth patterns according to rapid weight gain (RWG) and infant feeding practices during the first 120 days and whether infant feeding practices mediated the association between RWG in the first semester of life and subsequent body mass index (BMI) z-score in children from age 1 to 6. (1) Methods: 862 children from the Growth and Feeding during Lactation and Early Childhood in Children of Aragon study (CALINA in Spanish) were examined. Repeated-measures ANOVA analyses were conducted to assess growth trajectories according to RWG and type of feeding practice. The product of coefficients mediation method was used to assess the potential contribution of infant feeding practices to the association between RWG and BMI z-score. Mediation models were conducted using IBM SPSS-PROCESS Statistics for Windows, Version 26.0. Armonk, NY: IBM Corp. (2) Results: BMI and weight z-score trajectories were significantly higher in the RWG group and the formula-fed group. No significant differences were found regarding height. Infant feeding practices did not mediate the association between RWG and BMI z-score but were associated with BMI at 6 years. (3) Conclusions: Infant feeding practices and RWG determine different growth trajectories of BMI and weight during childhood. Although infant feeding practices did not mediate the association between early RWG and BMI later in life, formula feeding is independently related to higher BMI growth patterns later in childhood.

Community context, birth cohorts and childhood body mass index trajectories: Evidence from the China nutrition and health survey 1991-2011.

Childhood overweight and obesity have shown an increase in recent birth cohorts. China has undergone rapid socioeconomic transitions accompanied by lifestyle changes that have profoundly affected the physical growth of children. Less empirical research has considered the role of community context on the cohort effects of children's body mass index (BMI) z-score trajectories. We used the mixed effect models for repeated measurements with restricted cubic spline to predict the BMI z-score trajectories in children aged 1-17 years, influenced by different birth cohorts and community context using data from the China Health and Nutrition Survey from 1991 to 2011, and stratified by sex. Results indicated that the mean of BMI z-scores of children aged 1-17 years have increased in the 2000s cohort. Community context contributed to significant differences in BMI z-score increase with age from middle childhood, and this trend of community inequalities divergences in middle childhood in recent birth cohorts. Therefore, to promote equitable growth for all children in China, policy interventions focusing on the community context may have far-reaching effects on the health of children and adolescents.

Integration of an interpretable machine learning algorithm to identify early life risk factors of childhood obesity among preterm infants: a prospective birth cohort

BackgroundThe early life risk factors of childhood obesity among preterm infants are unclear and little is known about the influence of the feeding practices. We aimed to identify early life risk factors for childhood overweight/obesity among preterm infants and to determine feeding practices that could modify the identified risk factors.MethodsA total of 338,413 mother-child pairs were enrolled in the Jiaxing Birth Cohort (1999 to 2013), and 2125 eligible singleton preterm born children were included for analyses. We obtained data on health examination, anthropometric measurement, lifestyle, and dietary habits of each participant at their visits to clinics. An interpretable machine learning-based analytic framework was used to identify early life predictors for childhood overweight/obesity, and Poisson regression was used to examine the associations between feeding practices and the identified leading predictor.ResultsOf the eligible 2125 preterm infants (863 [40.6%] girls), 274 (12.9%) developed overweight/obesity at age 4–7 years. We summarized early life variables into 25 features and identified two most important features as predictors for childhood overweight/obesity: trajectory of infant BMI (body mass index) Z-score change during the first year of corrected age and maternal BMI at enrollment. According to the impacts of different BMI Z-score trajectories on the outcome, we classified this feature into the favored and unfavored trajectories. Compared with early introduction of solid foods (≤ 3 months of corrected age), introducing solid foods after 6 months of corrected age was significantly associated with 11% lower risk (risk ratio, 0.89; 95% CI, 0.82 to 0.97) of being in the unfavored trajectory.ConclusionsThe trajectory of BMI Z-score change within the first year of life is the most important predictor for childhood overweight/obesity among preterm infants. Introducing solid foods after 6 months of corrected age is a recommended feeding practice for mitigating the risk of being in the unfavored trajectory.

Association between prediabetes diagnosis and body mass index trajectory of overweight and obese adolescents.

Prediabetes awareness in adults has been associated with improved weight management. Whether youth with prediabetes diagnosis experience similar improvements is unknown. To investigate the association between prediabetes identification and body mass index (BMI) trajectory in overweight and obese adolescents. Youth who were followed longitudinally in a large academic-affiliated primary care network and who were overweight/obese while 10 to 18 years old. Retrospective cohort study. Subjects were categorized as "screened" if at least 1 hemoglobin A1c (HbA1c) result was available. Time series analysis was used to determine the difference in difference (DID) in BMI Z-score (BMI-Z) slope before and after HbA1c between: (a) screened youth found to have prediabetes-range HbA1c (5.7%-6.4%, 39-46 mmol/mol) versus normal HbA1c and (b) screened versus age-matched unscreened obese youth. A total of 4184 (55.6% female) screened subjects (median follow-up 9.7 years) were included. In which, 637 (15.2%) had prediabetes-range HbA1c. Prediabetes was associated with a greater decrease in BMI-Z slope than normal HbA1c (DID: -0.023/year [95% CI: -0.042 to -0.004]). When compared to age-matched unscreened subjects (n = 2087), screened subjects (n = 2815) experienced a greater decrease in BMI-Z slope after HbA1c than unscreened subjects at a matched age (DID: -0.031/y [95% CI -0.042 to -0.021]). BMI-Z trajectory improved more among youth with prediabetes-range HbA1c but also stabilized in screened youth overall. Prospective studies are needed to identify provider- and patient-level drivers of this observation.

Trajectories of hemoglobin A1c and body mass index z-score over four decades among 2 to 18 year olds with type 1 diabetes.

To determine trajectories of glycemic control and body mass index (BMI) z-score in a large pediatric sample with type 1 diabetes (T1D) over a 38-year period, and to evaluate sex differences and temporal changes in the prevalence of these trajectories. We conducted a longitudinal, retrospective study of 7002 2 to 18 year olds with T1D followed between 1978 and 2016 at a single center. Group-based modeling was used to identify trajectories for hemoglobin A1c (HbA1c) and BMI z-score. Multinomial logistic regression identified predictors of membership to less favorable glycemic trajectories. Group-based modeling yielded 5 HbA1c trajectories. A total of 86% of the sample fell within 3 trajectories that were largely stable across childhood and adolescence, and 14% fell within 2 trajectories characterized by marked deterioration beginning in pre-adolescence. Girls were more likely to be in the HbA1c trajectory with the highest starting HbA1c and significant deterioration during adolescence, and in the highest two BMI z-score trajectories. Patients with non-white race had the highest odds of belonging to a less favorable HbA1c trajectory. Prevalence of the high stable HbA1c trajectory decreased and prevalence of the low stable HbA1c trajectory increased over the study period. A minority of youth with T1D experienced deterioration of glycemic control during adolescence. Girls were more likely to belong to the worst HbA1c trajectory and to BMI z-score trajectories in the overweight/obese range, which may increase cardiometabolic risk. Addressing racial/ethnic disparities in glycemic control should remain a priority. Advances in T1D management correlated with favorable shifts in HbA1c trajectory prevalence.

BMI Z-Score Trajectories in Youth with T1D—An International Comparison

Obesity in youth with type 1 diabetes (T1D) has emerged as a challenge in care. Data from the Australasian Diabetes Data Network (ADDN), Diabetes Prospective Follow-up (DPV) in Austria and Germany, and T1D Exchange (T1DX) registry in the U.S. were compared to assess international differences in BMI z-score trajectories in youth with T1D. Longitudinal data from 11,513 participants between ages 8-17 years with T1D duration ≥1 year. and ≥5 aggregated body mass index (BMI) values (ADDN: N=1073, 46% female, mean HbA1c 8.3%; DPV: N=8722, 46% female, mean HbA1c 7.8%; T1DX: N=1718, 45% female, mean HbA1c 8.6%) were analyzed. Participants diagnosed with celiac and/or thyroid disease were excluded. Latent class growth modeling by Nagin was used to identify subgroups following similar BMI z-score trajectories. Five distinct trajectories were identified in ADDN and T1DX participants, and six in DPV (Figure). In all registries most participants in ADDN and T1DX maintained weight status over time. However, obese (BMI z-score ≥2) participants from ADDN achieved weight loss over time, compared to obese participants in T1DX, whose BMI SD increased during the teen years. In DPV, there were trajectories indicating dramatic weight gain/loss during puberty. Further analysis by sex and minority status will help to understand the within-registry and between-registry variation and may help target clinical interventions to achieve healthy weight in youth with T1D. Disclosure M. Wu: None. H. Phelan: None. A. Schwandt: None. N.C. Foster: None. J. Couper: None. C. Steigleder-Schweiger: None. S.M. Willi: Advisory Panel; Self; Boehringer Ingelheim GmbH. Other Relationship; Self; Caladrius Biosciences, Inc.. Consultant; Self; GlaxoSmithKline plc., JAEB Center For Health Research. T. Jones: None. P. Kroschwald: None. D.M. Maahs: Advisory Panel; Self; Insulet Corporation. Consultant; Self; Abbott. Research Support; Self; Medtronic, Bigfoot Biomedical, Dexcom, Inc., Insulet Corporation, Roche Diabetes Care Health and Digital Solutions. N. Prinz: None. M.E. Craig: None.

Lower Body Mass Index Z-Score Trajectory During Early Childhood After the Birth of a Younger Sibling

ObjectiveThe objectives of this study were to examine differences in body mass index z-score (BMIZ) trajectory during early childhood among children with a younger sibling compared with those without and to test potential mediators. MethodsThis longitudinal cohort study included 6050 participants of the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B). Focal children's weight, height, sibship status, screen time, active play time, family dinner frequency, and diet quality were assessed at 9 months, 24 months, preschool, and kindergarten when available. A piecewise linear regression model was used to examine the association between sibling birth and focal child's subsequent BMIZ trajectory to kindergarten. Mediation by screen time, active play time, family dinner frequency, and diet quality was tested. ResultsBMIZ trajectory was lower among children who had a new sibling join the family before kindergarten compared to children who did not have a new sibling join the family by kindergarten. The association was strongest when new sibship occurred when the focal child was 48 to 66 months (b = –0.026, P = .044). The association was not mediated by screen time, active play time, family dinner frequency, or diet quality. ConclusionAmong a nationally representative cohort of US children, new sibship before kindergarten was associated with a lower BMIZ trajectory. Several common obesogenic risk factors did not explain the association.

Body mass index trajectories in the first two years and subsequent childhood cardio-metabolic outcomes: a prospective multi-ethnic Asian cohort study

We investigated body mass index (BMI) trajectories in the first 2 years of life in 1170 children from an Asian mother-offspring cohort in Singapore, and examined their predictors and associations with childhood cardio-metabolic risk measures at 5 years. Latent class growth mixture modelling analyses were performed to identify distinct BMI z-score (BMIz) trajectories. Four trajectories were identified: 73.2%(n = 857) of the children showed a normal BMIz trajectory, 13.2%(n = 155) a stable low-BMIz trajectory, 8.6%(n = 100) a stable high-BMIz trajectory and 5.0%(n = 58) a rapid BMIz gain after 3 months trajectory. Predictors of the stable high-BMIz and rapid BMIz gain trajectories were pre-pregnancy BMI, gestational weight gain, Malay and Indian ethnicity, while predictors of stable low-BMIz trajectory were preterm delivery and Indian ethnicity. At 5 years, children with stable high-BMIz or rapid BMIz gain trajectories had increased waist-to-height ratios [B(95%CI) 0.02(0.01,0.03) and 0.03(0.02,0.04)], sum of skinfolds [0.42(0.19,0.65) and 0.70(0.36,1.03)SD units], fat-mass index [0.97(0.32,1.63)SD units] and risk of obesity [relative risk 3.22(1.73,6.05) and 2.56 (1.19,5.53)], but not higher blood pressure. BMIz trajectories were more predictive of adiposity at 5 years than was BMIz at 2 years. Our findings on BMIz trajectories in the first 2 years suggest important ethnic-specific differences and impacts on later metabolic outcomes.