Hispanic and black US children's paths to high adolescent obesity prevalence

Using explainable machine learning and fitbit data to investigate predictors of adolescent obesity

Sociodemographic and lifestyle factors (sleep, physical activity, and sedentary behavior) may predict obesity risk in early adolescence; a critical period during the life course. Analyzing data from 2971 participants (M = 11.94, SD = 0.64 years) wearing Fitbit Charge HR 2 devices in the Adolescent Brain Cognitive Development (ABCD) Study, glass box machine learning models identified obesity predictors from Fitbit-derived measures of sleep, cardiovascular fitness, and sociodemographic status. Key predictors of obesity include identifying as Non-White race, low household income, later bedtime, short sleep duration, variable sleep timing, low daily step counts, and high heart rates (AUCMean = 0.726). Findings highlight the importance of inadequate sleep, physical inactivity, and socioeconomic disparities, for obesity risk. Results also show the clinical applicability of wearables for continuous monitoring of sleep and cardiovascular fitness in adolescents. Identifying the tipping points in the predictors of obesity risk can inform interventions and treatment strategies to reduce obesity rates in adolescents.

Obesity Incidence in U.S. Children and Young Adults: A Pooled Analysis

INTRODUCTION

Obesity prevalence among children and adolescents has risen sharply, yet there is a limited understanding of the age-specific dynamics of obesity as there is no single nationally representative cohort following children into young adulthood. Investigators constructed a pooled data set of 5 nationally representative panels and modeled age-specific obesity incidence from childhood into young adulthood.

METHODS

This longitudinal prospective follow-up used 718,560 person-years of observation in a pooled data set of 5 high-quality nationally representative panels-National Longitudinal Survey of Youth 1979 and 1997, National Longitudinal Study of Adolescent Health, and Early Childhood Longitudinal Study-Kindergarten cohorts of 1998 and 2011-constructed by the authors, covering 1980-2016. Differences in obesity incidence across birth cohorts and disparities in obesity incidence by sex and race/ethnicity (non-Hispanic Black, Hispanic, and non-Hispanic White) were tested in multivariate models. Data were analyzed from September 2018 to October 2021.

RESULTS

Obesity incidence increased by approximately 6% for each 1 year of age (hazard ratio=1.06, 95% CI=1.05, 1.07); however, incidence was nonlinear, exhibiting an inverted "U"-shaped pattern before 15 years of age and then rising from adolescence through 30 years. Obesity incidence more than doubled between the cohorts born in 1957-1965 and those born in 1974-1985 during adolescence. There was no significant change among those born in 1991-1994 and 2003-2006 up to age 15 years. Compared with non-Hispanic White children, non-Hispanic Black and Hispanic children had higher obesity incidence in all study cohorts. The magnitude of these disparities on the relative scale remained stable throughout the study period.

CONCLUSIONS

Although many children become obese before the age of 10, obesity incidence rises from about 15 years into early adulthood, suggesting that interventions are required at multiple developmental stages.

Ethnicity Strongly Influences Body Fat Distribution Determining Serum Adipokine Profile and Metabolic Derangement in Childhood Obesity

Background: Body fat content and distribution in childhood is influenced by sex and puberty, but interethnic differences in the percentage and distribution of body fat also exist. The abdominal visceral/subcutaneous fat ratio has been the main feature of body fat distribution found to associate with the serum adipokine profile and metabolic derangement in adulthood obesity. This has also been assumed for childhood obesity despite the known singularities of this disease in the pediatric age in comparison to adults. Objective: We aimed to investigate the effect of ethnicity, together with sex and pubertal status, on body fat content and distribution, serum adipokine profile, metabolic impairment and liver steatosis in children and adolescents with obesity. Patients and Methods: One hundred and fifty children with obesity (50% Caucasians/50% Latinos; 50% males/50% females) were studied. Body fat content and distribution were studied by whole body DXA-scan and abdominal magnetic resonance, and their relationships with liver steatosis (as determined by ultrasonography), glycemia, insulinemia, lipid metabolism, uric acid, total and HMW-adiponectin, leptin, leptin-receptor, and sex steroid levels were explored. Results: Latino patients had more severe truncal obesity (higher trunk/lower limb fat ratio, odds ratio 10.00; p < 0.05) and higher prevalence of liver steatosis than Caucasians regardless of sex or pubertal status, but there were no difference in the visceral/subcutaneous abdominal fat ratio, except for pubertal females. A higher trunk/lower limb fat ratio, but not the visceral/subcutaneous abdominal fat ratio, was associated with adipokine profile impairment (higher free leptin index and lower adiponectin levels), insulin resistance and dyslipidemia, and was further enhanced when liver steatosis was present (p < 0.05). A higher abdominal visceral/subcutaneous fat ratio was observed in prepubertal children (p < 0.01), except for Latino females, whereas predominant subcutaneous fat deposition was observed in adolescents. Conclusion: Ethnicity is one of the main determinants of increased trunk body fat accumulation in Latino children with obesity, which is best estimated by the trunk/lower limb fat ratio and related to the development of metabolic derangement and liver steatosis.

Prevalence, Patterns, and Predictors: A Statewide Longitudinal Study of Childhood Obesity

BACKGROUND

We examined prevalence, incidence, and trajectory of obesity from kindergarten through grade 8 in one of the first states to implement annual surveillance.

METHODS

Participants included 16,414 children enrolled in kindergarten in Arkansas in 2004 with complete body mass index (BMI) measurements in kindergarten and eighth grade. Repeated measures of weight status were entered in multiple linear and logistic regression models with demographics and family poverty status.

RESULTS

The prevalence of obesity (BMI ≥ 95th percentile) was lowest in kindergarten (14.9%), with subsequent incidence rates consistent at 4%. Prevalence and incidence peaked in eighth grade (24.5% and 4.9%, respectively), with 33.8% of children measuring obese at least once by eighth grade. Kindergarten obesity was a significant predictor of eighth grade obesity (odds ratio, 17.5; 95% confidence interval, 15.8-19.3). We found statistically significant 3-way interactions for sex, race, and time, suggesting unique patterns for Hispanic boys and black girls.

CONCLUSIONS

Our study documents unique longitudinal patterns of obesity from kindergarten through eighth grade that expand our understanding of risk. It demonstrates the value of public school health systems that collect routine administrative data about student BMI that is integrated with education records to foster program and policy discussions.

Childhood obesity prevention cluster randomized trial for Hispanic families: outcomes of the healthy families study

BACKGROUND

Obesity prevalence is disproportionately high among Hispanic children.

OBJECTIVES

The Healthy Families Study assessed the efficacy of a culturally targeted, family-based weight gain prevention intervention for Hispanic immigrant families with children ages 5-7 years.

METHODS

The study used a two-group, cluster randomized trial design, assigning 136 families (clusters) to the active intervention (weight gain prevention) and 136 families to attention control (oral health). The active intervention included a 4-month intensive phase (eight classes) and an 8-month reinforcement phase (monthly mail/telephone contact). Children's body mass index z-score (BMI-Z) was the primary outcome.

RESULTS

The BMI-Z growth rate of the active intervention group did not differ from the attention control group at short-term follow-up (median 6 months; 168 families, 206 children) or long-term follow-up (median 16 months; 142 families, 169 children). Dose response analyses indicated a slower increase in BMI-Z at short term among overweight/obese children who attended more intervention classes. Moderate physical activity on weekends increased at short term. Weekend screen time decreased at short term among those attending at least one class session.

CONCLUSION

Low class attendance likely impacted intention-to-treat results. Future interventions targeting this population should test innovative strategies to maximize intervention engagement to produce and sustain effects on weight gain prevention.

Food Consumption Patterns of Infants and Toddlers: Findings from the Feeding Infants and Toddlers Study (FITS) 2016

Background

The prevalence of obesity and type 2 diabetes continues to increase. These conditions disproportionately affect minorities and are associated with poor nutrition early in life. Current food-consumption patterns can inform pending dietary guidelines for infants and toddlers.

Objective

The aim of this study was to describe infant feeding, complementary feeding, and food and beverage consumption patterns of 0- to 23.9-mo-olds in the general population.

Methods

The Feeding Infants and Toddlers Study 2016 is a cross-sectional survey of caregivers of children aged <4 y. Dietary data were collected from a national random sample by using a 24-h dietary recall (n = 3235). The percentage of children consuming foods from >400 food groups was calculated. Differences in the percentage consuming between Hispanic, non-Hispanic white, and non-Hispanic black children aged 0-23.9 mo were evaluated with the use of ORs and 95% CIs.

Results

Eighty-three percent of 0- to 23.9-mo-olds (n = 2635) were ever breastfed, 34% of 0- to 3.9-mo-olds (n = 305) and 15% of 4- to 5.9-mo-olds (n = 295) were exclusively breastfed, and 24% of 12- to 14.9-mo-olds (n = 412) consumed breast milk on the day of the recall. Complementary foods were more likely to be introduced before 4 mo in formula-fed infants (27%) than in infants who did not consume formula (5%). Half of 4- to 5.9-mo-olds consumed iron-fortified infant cereal, but few consumed iron-rich meats. Among toddlers (12-23.9 mo; n = 1133), >20% consumed no servings of fruit or vegetables on the day of the recall, approximately half consumed 100% fruit juice, and one-quarter to one-third consumed a sugar-sweetened beverage (SSB).

Conclusions

Breastfeeding initiation and duration have improved, but exclusivity remains low. Low consumption of iron-rich foods, fruit, and vegetables and lack of variety in vegetable consumption are problems. Efforts to reduce the consumption of SSBs and 100% fruit juice are warranted in early childhood.

Factors Associated With Length of Stay and 30-Day Revisits in Pediatric Acute Pancreatitis

OBJECTIVE

The objective of the study was to identify factors associated with length of stay (LOS) and 30-day hospital revisit for patients hospitalized with acute pancreatitis (AP).

METHOD

Multicenter, retrospective cohort study using the Pediatric Health Information System database. Multilevel linear and logistic regression was used to identify factors independently associated with the primary outcome variables of LOS and 30-day hospital revisit in children aged 1 and 18 years discharged with a primary discharge diagnosis of AP from participating hospitals between 2008 and 2013.

RESULTS

For the 7693 discharges, median LOS was 4 days (interquartile range 3-7 days) and 30-day revisit rate 17.6% (n = 1356). Discharges were primarily girls (55%), Caucasian (46%), and 6 years old or older (85%). On multilevel regression, factors independently associated with both longer LOS and higher revisit odds included malignant and gastrointestinal complex chronic conditions (CCCs) and total parenteral nutrition use while hospitalized. Male gender was associated with both lower LOS (adjusted length of stay = -0.6 days, 95% confidence interval [CI] = -0.8 to -0.4) and decreased revisit odds (aOR 0.85; 95% CI = 0.74 to 0.97). Hispanic ethnicity was associated with increased LOS (adjusted length of stay = +0.8 days, 95% CI = +0.5 to +1.1), but no change in revisit odds.

CONCLUSIONS

Certain demographic and clinical factors, including gender, ethnicity, and type of CCC, were independently associated with LOS and risk of 30-day hospital revisit for pediatric AP. Children with malignant and gastrointestinal CCCs who require total parenteral nutrition are at highest risk for both longer LOS and hospital revisit when admitted with AP. These patient populations may benefit from intensive care coordination when hospitalized for AP.

Associations of neonatal adiponectin and leptin with growth and body composition in African American infants

BACKGROUND

Cord blood adiponectin and leptin concentrations are associated with birth weight and adiposity. Birth size and rate of infant weight gain are associated with future obesity risk. However, it is unclear whether biomarkers reflecting the intrauterine environment are predictive of infant prospective body composition change.

OBJECTIVES

To examine whether cord blood adiponectin and leptin are predictive of neonatal adiposity and fat mass (FM) accrual to 3 months of age.

METHODS

Participants (n = 36) were healthy African American infants. Leptin and adiponectin concentrations were measured in umbilical cord blood. At 2 weeks and 3 months, infant body composition was assessed via air displacement plethysmography. Weight-for-length z-scores (WLZ) were calculated using World Health Organization standards. Multiple linear regression was used to examine associations of cord blood adiponectin and leptin with birth WLZ; WLZ, FM and fat-free mass at 2 weeks, and the conditional change in these variables from 2 weeks to 3 months (body composition at 3 months adjusted for body composition at 2 weeks).

RESULTS

Adiponectin was positively associated with FM at 2 weeks (r = 0.45, P < 0.01), but inversely associated with conditional FM change from 2 weeks to 3 months of age (r = -0.38, P < 0.05). Leptin was not significantly associated with infant body composition.

CONCLUSIONS

Adiponectin may be a marker for FM accrual in African American infants, a relatively understudied population with a high long-term obesity risk. Mechanistic studies are needed to determine whether adiponectin directly influences infant growth or is simply a maker reflective of other ongoing biological changes after birth.

A Home Visiting Parenting Program and Child Obesity: A Randomized Trial

BACKGROUND

Young children living in historically marginalized families are at risk for becoming adolescents with obesity and subsequently adults with increased obesity-related morbidities. These risks are particularly acute for Hispanic children. We hypothesized that the prevention-focused, socioecological approach of the "Minding the Baby" (MTB) home visiting program might decrease the rate of childhood overweight and obesity early in life.

METHODS

This study is a prospective longitudinal cohort study in which we include data collected during 2 phases of the MTB randomized controlled trial. First-time, young mothers who lived in medically underserved communities were invited to participate in the MTB program. Data were collected on demographics, maternal mental health, and anthropometrics of 158 children from birth to 2 years.

RESULTS

More children in the intervention group had a healthy BMI at 2 years. The rate of obesity was significantly higher (P < .01) in the control group (19.7%) compared with the intervention group (3.3%) at this age. Among Hispanic families, children in the MTB intervention were less likely to have overweight or obesity (odds ratio = 0.32; 95% confidence interval: 0.13-0.78).

CONCLUSIONS

Using the MTB program, we significantly lowered the rate of obesity among 2-year-old children living in low-socioeconomic-status communities. In addition, children of Hispanic mothers were less likely to have overweight or obesity at 2 years. Given the high and disproportionate national prevalence of Hispanic young children with overweight and obesity and the increased costs of obesity-related morbidities, these findings have important clinical, research, and policy implications.

Short Sleep Duration Is Associated With Eating More Carbohydrates and Less Dietary Fat in Mexican American Children

Study Objective

Short sleep duration is a risk factor for childhood obesity. Mechanisms are unclear, but may involve selection of high carbohydrate foods. This study examined the association between estimated sleep duration and macronutrient intake as percentages of total energy among Mexican American (MA) 9-11 year olds.

Methods

This cross-sectional study measured diet using two 24-hour recalls and estimated sleep duration using hip-worn accelerometry in MA children (n = 247) who were part of a cohort study. Child and maternal anthropometry were obtained; mothers reported on demographic information. Using linear regression, we examined the relationship of sleep duration with energy intake, sugar intake, and the percentage of energy intake from carbohydrates, fat, and protein.

Results

Children were 47% male; mean age was 10 (SD = 0.9) years. Mean sleep duration was 9.6 (SD = 0.8) hours; 53% were overweight/obese, with a mean energy intake of 1759 (SD = 514) calories. Longer sleep duration was independently associated with a lower percentage of energy intake from carbohydrates (β = -0.22, p < .01) and a higher percentage of energy from fat (β = 0.19, p < .01), driven by the percentage of energy from polyunsaturated fatty acids (PUFA; β = 0.17, p < .05). No association was found with the intake of energy or total sugars, or the percent of calories from protein.

Conclusions

MA children who slept longer consumed diets with a lower percentage of calories from carbohydrates and a higher percentage from fat, especially from PUFA. Short sleep duration may be a risk factor for food cravings that are high in carbohydrate content and may displace heart-healthy dietary fat, and thereby increase obesity risk among children.

Full fat milk consumption protects against severe childhood obesity in Latinos

Consumption of non- or low-fat dairy products is recommended as a strategy to lower the risk of childhood obesity. However, recent evidence suggests that consumption of whole fat dairy products may, in fact, be protective against obesity. Our objective was to determine the association between milk fat consumption and severe obesity among three-year-old Latino children, a population with a disproportionate burden of obesity and severe obesity. 24-hour-dietary recalls were conducted to determine child intake in San Francisco based cohort recruited in 2006–7. Mother-child dyads were weighed and measured. The 24-hour recall data was analyzed to determine participants' consumption of whole milk, 2% milk, and 1% milk. The milk consumption data was used to calculate grams of milk fat consumed. The cross-sectional association between milk fat intake and severe obesity (BMI ≥ 99th percentile) was determined using multivariable logistic regression. Data were available for 145 children, of whom 17% were severely obese. Severely obese children had a lower mean intake of milk fat (5.3 g vs. 8.9 g) and fewer drank any milk (79% versus 95% for not severely obese children (p < 0.01)). Among the potential confounders assessed, maternal BMI and maternal marital status were associated with severe obesity and were included in a multivariate model. In the multivariate model, higher milk fat consumption was associated with lower odds of severe obesity (OR 0.88 CI 0.80–0.97). Higher milk fat consumption is associated with lower odds of severe obesity among Latino preschoolers. These results call into question recommendations that promote consumption of lower fat milk.

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Current guidelines recommend that children consume low-fat milk.

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Prior literature suggests that full fat milk may protect against obesity.

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We evaluated how milk fat consumption relates to weight in Latino children.

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We found that milk fat consumption was protective against severe obesity.

Age at adiposity rebound and body mass index trajectory from early childhood to adolescence; differences by breastfeeding and maternal immigration background

OBJECTIVE

This paper aims to assess association between breastfeeding and maternal immigration background and body mass index development trajectories from age 2 to 16 years.

METHODS

A cohort of children born in Stockholm during 1994 to 1996 was followed from age 2 to 16 years with repeated measurement of height and weight at eight time points (n = 2278). Children were categorized into groups by breastfeeding status during the first 6 months of life and maternal immigration background. Body mass index (BMI) trajectories and age at adiposity rebound were estimated using mixed-effects linear models.

RESULTS

Body mass index trajectories were different by breastfeeding and maternal immigration status (P-value < 0.0001). Compared with exclusively breastfed counterparts, never/short breastfed children of Swedish mothers had a higher BMI trajectory, whereas never/short breastfed children of immigrant mothers followed a lower BMI trajectory. Ages at adiposity rebound were earlier for higher BMI trajectories regardless of maternal immigration background.

CONCLUSION

Differences in BMI trajectories between offspring of immigrant and of Swedish mothers suggest a lack of beneficial association between breastfeeding and long-term BMI development among children of immigrant mothers. Given the relation between long-term BMI development and risk of overweight/obesity, these differences challenge the notion that exclusive breastfeeding is always beneficial for children's BMI development and subsequent risk of overweight/obesity.

Population-Level Measures to Predict Obesity Burden in Public Schools: Looking Upstream for Midstream Actions

PURPOSE

To estimate school-level obesity burden, as reflected in prevalence of obesity, based on the characteristics of students' socioeconomic and geographic environments.

DESIGN

Secondary analysis of cross-sectional data.

SETTING

Public schools (N = 504) from 43 of 67 counties in Pennsylvania.

PARTICIPANTS

Kindergarten through grade 12 students (N = 255 949).

MEASURES

School-level obesity prevalence for the year 2014 was calculated from state-mandated student body mass index (BMI) measurements. Eighteen aggregate variables, characterizing schools and counties, were retrieved from federal data sources.

ANALYSIS

Three classification variables-excess weight (BMI ≥ 85th percentile), obesity (BMI ≥ 95th percentile), and severe obesity (BMI > 35% or 120% of 95th percentile)-each with 3 groups of schools (low-, average-, and high-prevalence) were created for discriminant function analysis, based on state mean and standard deviation of school distribution. Analysis tested each classification model to reveal school- and county-level dimensions on which school groups differed from each other.

RESULTS

Discriminant functions for obesity, which contained school enrollment, percentage of students receiving free/reduced-price lunch, percentage of black/Hispanic students, school location (suburban/other), percentage of county adults with postsecondary education, and percentage of county adults with obesity, yielded 67.86% correct classification (highest accuracy), compared to 34.23% schools classified by chance alone.

CONCLUSION

In the absence of mandated student BMI screenings, the model developed in this study can be used to identify schools most likely to have high obesity burden and, thereafter, determine dissemination of enhanced resources for the implementation of proven prevention policies and programs.

Early Childhood Disadvantage for Sons of Mexican Immigrants: Body Mass Index Across Ages 2-5

PURPOSE

To distinguish the origins of higher weight status and determine when and why intra- and interracial/ethnic disparities emerge.

DESIGN

The study used a longitudinal analysis of the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B).

SETTING

The study was conducted in the United States.

SUBJECTS

Participants were children of non-Hispanic white mothers and children of U.S.- and foreign-born mothers of Mexican origin from a nationally representative sample of children born in the year 2001 (N ≈ 3700).

MEASURES

The Centers for Disease Control and Prevention growth charts determined sex- and age-specific weight status. Covariates were obtained from birth certificate records and parent interviews.

ANALYSIS

Frequencies, growth curve trajectories, and ordinary least squares regression examined body mass index (BMI) and obesity across survey waves.

RESULTS

Compared to their peers with non-Hispanic white mothers, children of Mexican-heritage mothers have higher average BMI and greater rates of obesity. The BMI of boys with Mexican-born mothers is higher relative to whites and children of U.S.-born Mexican mothers across early childhood, increasing sharply at about age 4.5 years. This divergence is driven by increases in the BMI of boys, as girls do not show the same growth. A number of measures, including descriptors of children's nutritional intake, lifestyle factors, and acculturation, do not explain the increased obesity rates among sons of Mexican mothers.

CONCLUSION

Despite favorable perinatal health and weight, Mexican-American sons of foreign-born mothers show disadvantages in BMI that emerge close to the start of kindergarten.

Exploring Categorical Body Mass Index Trajectories in Elementary School Children

BACKGROUND

Studies of body mass index (BMI) change have focused on understanding growth trajectories from childhood to adolescence and adolescence to adulthood, but few have explored BMI trajectories solely in elementary (grades K-5) school children. This report complements these studies by exploring changes in obesity status using analytic methods developed to investigate categorical changes in life-course events.

METHODS

Sequences of a 4-state BMI variable (underweight, normal, overweight, and obese) were calculated using height and weight data collected annually (2008-2013) from 414 kindergarten and first-grade students participating in the Community and Schools Together (CAST) project. These sequences were explored using the TraMineR software package to investigate the distribution of sequences and states, calculate transition rates among states, and examine clustering of sequences.

RESULTS

Aggregated cluster solutions were identified consisting of either 4 clusters (normal, stepped, mixed, and obese) or 3 clusters (aggregation of obese cluster cases into stepped cluster) with membership in the former predicted by ethnicity and socioeconomic status (SES) and the latter by SES alone. Transition rate patterns among states varied markedly by cluster and state.

CONCLUSION

The finding of early emergence of stable obesity states, especially in Hispanic children confirms the need for early childhood interventions to influence BMI.

Latino Parents' Insight on Optimal Sleep for Their Preschool-Age Child: Does Context Matter?

OBJECTIVE

Insufficient sleep is a risk factor for pediatric obesity. Latino children are among those groups in which both short sleep duration and obesity are prevalent. Therefore, this study sought to explore Latino parents' views about ideal sleep duration and sleep-related practices for their preschool-age children in an urban setting.

METHODS

Between October 2013 and January 2014, Latino parents of 2- to 5-year-old children were interviewed at 3 pediatric clinics (San Francisco, Calif). Using a semistructured interview guide, parents were asked to describe bedtime routines and sleep practices of their preschool-age children, including behavioral, parental, social, and contextual factors that may affect children's sleep. Interviews were conducted in Spanish and English. Parents also completed a brief survey on demographic information. Interviews were analyzed on the basis of a priori and emergent themes.

RESULTS

Latino parents (n = 18) were mostly female, with a mean age of 31 years; most were foreign born; and more than half had a monthly household income of $2000 or less. The following themes emerged: parents' ideas about optimal sleep duration for their preschool-age child, consistent bedtime routines, room sharing and bed sharing, parent work and child school schedules that affect children's sleep, and crowded housing and neighborhood noise that disrupt children's sleep.

CONCLUSIONS

These findings increase our understanding of the factors related to achieving optimal sleep duration among Latino children living in urban and often crowded housing. Findings could be used to inform future research on how to increase parental knowledge of healthy sleep practices and adequate sleep among Latino parents of young children.

A Systematic Review of Literature on Culturally Adapted Obesity Prevention Interventions for African American Youth

Obesity and overweight prevalence in African American (AA) youth continues to be one of the highest of all major ethnic groups, which has led researchers to pursue culturally based approaches as a means to improve obesity prevention interventions. The purpose of this systematic review was to evaluate culturally adapted obesity prevention interventions targeting AA youth. A search of electronic databases, limited to multicomponent culturally adapted obesity prevention controlled trials from 2003 to 2013, was conducted for key terms. Eleven studies met inclusion criteria. We used the PEN-3 model to evaluate the strengths and weaknesses of interventions as well as to identify cultural adaptation strategies. The PEN-3 model highlighted the value of designing joint parent-youth interventions, building a relationship between AA mentors and youth, and emphasizing healthful activities that the youth preferred. The PEN-3 model shows promise as an overarching framework to develop culturally adapted obesity interventions.

Two Worlds of Obesity: Ethnic Differences in Child Overweight/Obesity Prevalence and Trajectories

OBJECTIVES

Research on childhood obesity has examined the prevalence of overweight and obesity during childhood and developmental trajectories. This study focuses on the extent to which Hispanic and non-Hispanic white elementary students differ in prevalence of overweight and obesity by grade level, time, gender, and school setting. It also focuses on comparison of the trajectories in weight status for the Hispanic and non-Hispanic white students.

METHODS

BMI values were examined both using standard scores (z-scores) and as categorical variables. Cross-sectional data from 4 years were used to examine prevalence, and panel data across 2-year periods examined trajectories. Descriptive statistics and mixed models, controlling for school setting, were used.

RESULTS

Hispanic students began first grade with higher prevalence of obesity and overweight, and the differences were larger in higher grades and later years. The majority of students had stable weight status over the 2-year periods of the trajectory analysis, but Hispanic students began the panel with higher BMI-Z values and were more likely to increase and less likely to decrease BMI-Z.

CONCLUSIONS

The findings suggest that the degree of childhood overweight/obesity, especially among Hispanics, is substantial and will likely have profound impacts on adult obesity and other associated health issues in the future. Findings confirm the need for early childhood interventions to influence BMI.

Electronic health records and community health surveillance of childhood obesity

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.

Population-level obesity surveillance: monitoring childhood body mass index z-score in a safety-net system

OBJECTIVE

To determine the utility of repeated patient-level body mass index (BMI) measurements among higher-risk patients seen at safety-net clinics as a community-level monitoring tool for overweight and obesity population trends.

METHODS

Data from a network of urban, federally qualified community health centers with computerized tracking of BMI at sequential outpatient visits were analyzed. We performed a longitudinal observational study over 8 years (2005-2012) with children stratified by weight status groups on the basis of BMI. Changes in BMI z-scores were used to estimate population trends among children 2 to 11 years old, with at least 2 visits (at least 1 year apart), for whom weight and height were measured.

RESULTS

Among children (n = 33,542), the rate of overweight was 16% and rate of obesity was 18% at their last visit. Children were followed for an average of 3.24 ± 1.76 years to measure trends and change in weight status from earlier to later childhood. Children who were obese at first visit had increased odds (adjusted odds ratio 27.8, 95% confidence interval 25.6-30.2) of being obese by last visit. Mean change in BMI z-score per person-year of observation was 0.10 ± 0.38, with a differing rate of change based on weight status category at last visit (not overweight = 0.06 ± 0.39; overweight = 0.17 ± 0.34; obese = 0.19 ± 0.36). Change in BMI z-score per person-year decreased for 40% of obese children; however, their weight status group remained unchanged.

CONCLUSIONS

Childhood obesity prevalence was high, with substantial progression to overweight and obesity from first to last visit. Clinically derived BMI z-score per person-year measures can effectively show population trends not observed using standard weight status categories.

What can providers learn from childhood body mass index trajectories: a study of a large, safety-net clinical population

OBJECTIVE

To describe childhood weight gain using body mass index (BMI) z-score trajectories in a low-income urban safety-net population and identify among gender- and race/ethnicity-specific groups any trends for increased risk.

METHODS

A retrospective cohort study was conducted among 2- to 12-year-old patients (2006-2013) visiting a safety-net provider. BMI z-score trajectories were calculated overall, for gender- and race/ethnicity-specific groups, and for peak BMI percentile subgroups to describe weight gain longitudinally.

RESULTS

From 2006 to 2013, a total of 26,234 eligible children were followed for an average of 3.7 years. At baseline (mean age, 4.2 years), 74% of patients were at a normal weight compared to 65% at most recent observation (mean age, 7.8 years). All gender and race/ethnicity subgroups showed increasing average BMI z-scores during childhood. Children consistently under the 50th percentile and those of white race had the most stable BMI z-score trajectories. BMI z-score increased with increasing age in all subgroups. Hispanic boys and black girls had the most significant increase in BMI z-score during this observation period. Children observed in early childhood and whose BMI exceeded the 95th percentile at any time were often already overweight (20%) or obese (36%) by 3 years of age.

CONCLUSIONS

The entire population demonstrated an upward trend in BMI z-score trajectory. This trend was most notable among black girls and Hispanic boys. Many obese children were already overweight by age 3, and persistence of obesity after 3 years of age was high, suggesting that intervention before age 3 may be essential to curbing unhealthy weight trajectories.

Race/ethnic disparities in early childhood BMI, obesity and overweight in the United Kingdom and United States

OBJECTIVE

Racial/ethnic patterning in the risk of obesity and overweight has been observed in early childhood; however, little research has compared these disparities between the United Kingdom (UK) and United States (US) using detailed ethnic classifications. We use comparable nationally representative cohort studies to examine racial/ethnic disparities in mean body mass index (BMI) and in the odds of obesity/overweight in the UK and US. The contribution of sociodemographic, cultural and family routine factors are assessed.

METHODS

Data on BMI, obesity and overweight in 5-year-old children from the MCS (Millennium Cohort Study) and ECLS-B (Early Childhood Longitudinal Study, Birth Cohort) were examined. We investigated race/ethnic disparities in mean BMI and in the odds of obesity and overweight, as compared to normal weight. We assessed the independent contribution of sociodemographic, cultural and family routine factors to observed disparities.

RESULTS

In the UK, after adjustment for sociodemographic, cultural and family routine factors and maternal BMI, we found Black Caribbean children to have higher odds ratio (OR=1.7, confidence interval (CI)=1.1-2.6), Pakistani children to have lower odds of obesity (OR=0.60, CI=0.37-0.96) and Black African children were more likely to be overweight (OR=1.40, CI=1.04-1.88). In the US, in fully adjusted models, there were no race/ethnic disparities in children's odds of obesity and overweight.

CONCLUSION

Disparities for Bangladeshi children in the UK and Mexican, other Hispanic and American Indian children in the US can be explained by socioeconomic disadvantage, whereas a range of cultural and family characteristics partially explain disparities for other groups in the UK. Future public health initiatives focused on reducing risk of overweight and obesity should consider the diverse socioeconomic and cultural profiles of all race/ethnic groups.

Evaluation of bias in estimates of early childhood obesity from parent-reported heights and weights

OBJECTIVES

We evaluated bias in estimated obesity prevalence owing to error in parental reporting. We also evaluated bias mitigation through application of Centers for Disease Control and Prevention's biologically implausible value (BIV) cutoffs.

METHODS

We simulated obesity prevalence of children aged 2 to 5 years in 2 panel surveys after counterfactually substituting parameters estimated from 1999-2008 National Health and Nutrition Examination Survey data for prevalence of extreme height and weight and for proportions obese in extreme height or weight categories.

RESULTS

Heights reported below the first and fifth height-for-age percentiles explained between one half and two thirds, respectively, of total bias in obesity prevalence. Bias was reduced by one tenth when excluding cases with height-for-age and weight-for-age BIVs and by one fifth when excluding cases with body mass-index-for-age BIVs. Applying BIVs, however, resulted in incorrect exclusion of nonnegligible proportions of obese children.

CONCLUSIONS

Correcting the reporting of children's heights in the first percentile alone may reduce overestimation of early childhood obesity prevalence in surveys with parental reporting by one half to two thirds. Excluding BIVs has limited effectiveness in mitigating this bias.

A health literate approach to the prevention of childhood overweight and obesity

OBJECTIVE

To describe a systematic assessment of patient educational materials for the Growing Right Onto Wellness (GROW) trial, a childhood obesity prevention study targeting a low health literate population.

METHODS

Process included: (1) expert review of educational content, (2) assessment of the quality of materials including use of the Suitability Assessment of Materials (SAM) tool, and (3) material review and revision with target population.

RESULTS

12 core modules were developed and assessed in an iterative process. Average readability was at the 6th grade reading level (SMOG Index 5.63 ± 0.76, and Fry graph 6.0 ± 0.85). SAM evaluation resulted in adjustments to literacy demand, layout & typography, and learning stimulation & motivation. Cognitive interviews with target population revealed additional changes incorporated to enhance participant's perception of acceptability and feasibility for behavior change.

CONCLUSION

The GROW modules are a collection of evidence-based materials appropriate for parents with low health literacy and their preschool aged children, that target the prevention of childhood overweight/obesity.

PRACTICE IMPLICATIONS

Most trials addressing the treatment or prevention of childhood obesity use written materials. Due to the ubiquitous prevalence of limited health literacy, our described methods may assist researchers in ensuring their content is both understood and actionable.

Simulation models for socioeconomic inequalities in health: a systematic review

Background: The emergence and evolution of socioeconomic inequalities in health involves multiple factors interacting with each other at different levels. Simulation models are suitable for studying such complex and dynamic systems and have the ability to test the impact of policy interventions in silico. Objective: To explore how simulation models were used in the field of socioeconomic inequalities in health. Methods: An electronic search of studies assessing socioeconomic inequalities in health using a simulation model was conducted. Characteristics of the simulation models were extracted and distinct simulation approaches were identified. As an illustration, a simple agent-based model of the emergence of socioeconomic differences in alcohol abuse was developed. Results: We found 61 studies published between 1989 and 2013. Ten different simulation approaches were identified. The agent-based model illustration showed that multilevel, reciprocal and indirect effects of social determinants on health can be modeled flexibly. Discussion and Conclusions: Based on the review, we discuss the utility of using simulation models for studying health inequalities, and refer to good modeling practices for developing such models. The review and the simulation model example suggest that the use of simulation models may enhance the understanding and debate about existing and new socioeconomic inequalities of health frameworks.

Using Discrete-time Event History Fertility Models to Simulate Total Fertility Rates and Other Fertility Measures

Event history models, also known as hazard models, are commonly used in analyses of fertility. One drawback of event history models is that the conditional probabilities (hazards) estimated by event history models do not readily translate into summary measures, particularly for models of repeatable events, like childbirth. In this paper, we describe how to translate the results of discrete-time event history models of all births into well-known summary fertility measures: simulated age- and parity-specific fertility rates, parity progression ratios (PPRs), and the total fertility rate (TFR). The method incorporates all birth intervals, but permits the hazard functions to vary across parities. It also can simulate values for groups defined by both fixed and time-varying covariates, such as marital or employment life histories. We demonstrate the method using an example from the National Survey of Family Growth (NSFG) and provide an accompanying data file and Stata program.