Early excess weight gain of children in the Pima Indian population

Novel signals and polygenic score for height are associated with pubertal growth traits in Southwestern American Indians

Most genetic variants associated with adult height have been identified through large genome-wide association studies (GWASs) in European-ancestry cohorts. However, it is unclear how these variants influence linear growth during adolescence. This study uses anthropometric and genotypic data from a longitudinal study conducted in an American Indian community in Arizona between 1965-2007. Growth parameters (i.e. height, velocity, and timing of growth spurt) were derived from the Preece-Baines growth model, a parametric growth curve fitted to longitudinal height data, in 787 participants with height measurements spanning the whole period of growth. Heritability estimates suggested that genetic factors could explain 25% to 71% of the variance of pubertal growth traits. We performed a GWAS of growth parameters, testing their associations with 5 077 595 imputed or directly genotyped variants. Six variants associated with height at peak velocity (P < 5 × 10-8, adjusted for sex, birth year and principal components). Implicated genes include NUDT3, previously associated with adult height, and PACSIN1. Two novel variants associated with duration of growth spurt (P < 5 × 10-8) in LOC105375344, an uncharacterized gene with unknown function. We finally examined the association of growth parameters with a polygenic score for height derived from 9557 single nucleotide polymorphisms (SNPs) identified in the GIANT meta-analysis for which genotypic data were available for the American Indian study population. Height polygenic score was correlated with the magnitude and velocity of height growth that occurred before and at the peak of the adolescent growth spurt, indicating overlapping genetic architecture, with no influence on the timing of adolescent growth.

Adolescent Growth Spurt and Type 2 Diabetes Risk in Southwestern American Indians

Early puberty onset is associated with higher risk of diabetes, but most studies have not accounted for childhood factors that may confound the association. Using data from a study conducted in an Indigenous community in Arizona (1965-2007), we examined associations of timing and velocity of the adolescent growth spurt with type 2 diabetes, and whether these associations are mediated by childhood body mass index and insulinemia. Adolescent growth parameters were derived from the Preece-Baines growth model, a parametric growth curve fitted to longitudinal height data, for 861 participants with height measurements spanning the whole period of growth. In males, older age at take-off, age at peak velocity, and age at maturation were associated with decreased prevalence of diabetes (odds ratio (OR) = 0.43 per year, 95% confidence interval (CI): 0.27, 0.69; OR = 0.50, 95% CI: 0.35, 0.72; OR = 0.58, 95% CI: 0.41, 0.83, respectively), while higher velocity at take-off was associated with increased risk (OR = 3.47 per cm/year, 95% CI: 1.87, 6.42) adjusting for age, birth year, and maternal diabetes. Similar results were observed with incident diabetes. Our findings suggest that an early and accelerated adolescent growth spurt is a risk factor for diabetes, at least in males. These associations are only partially explained by measures of adiposity and insulinemia.

Increased Adiposity and Low Height-for-Age in Early Childhood Are Associated With Later Metabolic Risks in American Indian Children and Adolescents

BACKGROUND

Growth abnormalities in childhood have been related to later cardiometabolic risks, but little is known about these associations in populations at high risk of type 2 diabetes.

OBJECTIVES

We examined the associations of patterns of growth, including weight and height at ages 1-59 months, with cardiometabolic risk factors at ages 5-16 years.

METHODS

We linked anthropometric data collected at ages 1-59 months to cardiometabolic data obtained from a longitudinal study in a southwestern American Indian population at high risk of diabetes. Analyses included 701 children with ≥1 follow-up examination at ages 5-16 years. We derived age- and sex-specific weight-for-height z-scores (WHZ) and height-for-age z-scores (HAZ) at ages 1-59 months. We selected the highest observed WHZ and the lowest observed HAZ at ages 1-59 months and analyzed associations of z-scores and categories of WHZ and HAZ with cardiometabolic outcomes at ages 5-16 years. We used linear mixed-effects models to account for repeated measures.

RESULTS

Overweight/obesity (WHZ >2) at ages 1-59 months was significantly associated with increased BMI, fasting and 2-hour postload plasma glucose, fasting and 2-hour insulin, triglycerides, systolic blood pressure, diastolic blood pressure, and decreased HDL cholesterol at ages 5-16 years relative to normal weight (WHZ ≤1). For example, at ages 5-9 years, 2-hour glucose was 10.4 mg/dL higher (95% CI: 5.6-15.3 mg/dL) and fasting insulin was 4.29 μU/mL higher (95% CI: 2.96-5.71 μU/mL) in those with overweight/obesity in early childhood. Associations were attenuated and no longer significant when adjusted for concurrent BMI. A low height-for-age (HAZ < -2) at ages 1-59 months was associated with 5.37 mg/dL lower HDL (95% CI: 2.57-8.17 mg/dL) and 27.5 μU/mL higher 2-hour insulin (95% CI: 3.41-57.6 μU/mL) at ages 10-16 years relative to an HAZ ≥0.

CONCLUSIONS

In this American Indian population, findings suggest a strong contribution of overweight/obesity in early childhood to cardiometabolic risks in later childhood and adolescence, mediated through persistent overweight/obesity into later ages. Findings also suggest potential adverse effects of low height-for-age, which require confirmation.

Caring for American Indian and Alaska Native Children and Adolescents

American Indian and Alaska Native (AI/AN) populations have substantial health inequities, and most of their disease entities begin in childhood. In addition, AI/AN children and adolescents have excessive disease rates compared with the general pediatric population. Because of this, providers of pediatric care are in a unique position not only to attenuate disease incidence during childhood but also to improve the health status of this special population as a whole. This policy statement examines the inequitable disease burden observed in AI/AN youth, with a focus on toxic stress, mental health, and issues related to suicide and substance use disorder, risk of and exposure to injury and violence in childhood, obesity and obesity-related cardiovascular risk factors and disease, foster care, and the intersection of lesbian, gay, bisexual, transgender, queer, and Two-Spirit and AI/AN youth. Opportunities for advocacy in policy making also are presented.

Profile of Gut Hormones, Pancreatic Hormones and Pro-inflammatory Cytokines in New Zealand Maori

Background

Maori, indigenous people of New Zealand, have at least two times higher prevalence of obesity and diabetes in comparison with the general population in the country. Gut and pancreatic hormone profile differences as well as pro-inflammatory milieu may contribute to this disparity. The aim was to investigate the differences in gut hormones, pancreatic hormones and pro-inflammatory cytokines between Maori and non-Maori individuals.

Methods

This was a cross-sectional study. Fasting blood samples were collected to measure cholecystokinin, ghrelin, gastric inhibitory peptide, glicentin, glucagon-like peptide-1 and -2, oxyntomodulin, secretin, amylin, C-peptide, glucagon, insulin, pancreatic polypeptide, somatostatin, interleukin-6, monocyte chemoattractant protein-1 and tumour necrosis factor-α. Binary logistic regression analysis was conducted in one unadjusted and four adjusted statistical models adjusting for patient-, metabolic- and pancreatitis-related factors.

Results

A total of 8 Maori and 85 non-Maori individuals were included. Circulating levels of ghrelin, pancreatic polypeptide and interleukin-6 levels were significantly higher in Maori (P = 0.005, P = 0.003 and P = 0.011, respectively) in both unadjusted and all the four adjusted analyses. Other signaling molecules did not show consistently significant associations with ethnicity.

Conclusion

Profile of gut hormones, pancreatic hormones and pro-inflammatory cytokines appears to differ between Maori and non-Maori individuals, independent of obesity, diabetes and other covariates. This may go some way to explain the increased propensity to obesity and diabetes in the Maori population.

The effect of differing patterns of childhood body mass index gain on adult physiology in American Indians

OBJECTIVE

Identifying groups of individuals with similar patterns of body mass index (BMI) change during childhood may increase understanding of the relationship between childhood BMI and adult health.

METHODS

Discrete classes of BMI z-score change were determined in 1,920 American Indian children with at least four non diabetic health examinations between the ages of 2 and 18 years using latent class trajectory analysis. In subsets of subjects, data were available for melanocortin-4 receptor (MC4R) sequencing; in utero exposure to type 2 diabetes (T2D); or, as adults, oral glucose tolerance tests, onset of T2D, or body composition.

RESULTS

Six separate groups were identified. Individuals with a more modern birth year, an MC4R mutation, or in utero exposure to T2D were clustered in the two groups with high increasing and chronic overweight z-scores (P < 0.0001). The z-score classes predicted adult percent fat (P < 0.0001, partial r(2)  = 0.18 adjusted for covariates). There was a greater risk for T2D, independent from adult BMI, in three classes (lean increasing to overweight, high increasing, and chronic overweight z-scores) compared to the two leanest groups (respectively: HRR= 3.2, P = 0.01; 6.0, P = 0.0003; 11.6, P < 0.0001).

CONCLUSIONS

Distinct patterns of childhood BMI z-score change associate with adult adiposity and may impact risk of T2D.

The impact of interventions to prevent obesity or improve obesity related behaviours in children (0-5 years) from socioeconomically disadvantaged and/or indigenous families: a systematic review

BACKGROUND

Children from disadvantaged families including those from low socioeconomic backgrounds and Indigenous families have higher rates of obesity, making early intervention a priority. The aim of this study was to systematically review the literature to examine the effectiveness of interventions to prevent obesity or improve obesity related behaviours in children 0-5 years from socioeconomically disadvantaged or Indigenous families.

METHODS

Searches of major electronic databases identified articles published from 1993-2013 targeting feeding practices, anthropometric, diet, activity or sedentary behaviour outcomes. This was supplemented with snowballing from existing reviews and primary studies. Data extraction was undertaken by one author and cross checked by another. Quality assessments included both internal and external validity.

RESULTS

Thirty-two studies were identified, with only two (both low quality) in Indigenous groups. Fourteen studies had a primary aim to prevent obesity. Mean differences between intervention and control groups ranged from -0.29 kg/m(2) to -0.54 kg/m(2) for body mass index (BMI) and -2.9 to -25.6% for the prevalence of overweight/obesity. Interventions initiated in infancy (under two years) had a positive impact on obesity related behaviours (e.g. diet quality) but few measured the longer-term impact on healthy weight gain. Findings amongst pre-schoolers (3-5 years) were mixed, with the more successful interventions requiring high levels of parental engagement, use of behaviour change techniques, a focus on skill building and links to community resources. Less than 10% of studies were high quality. Future studies should focus on improving study quality, including follow-up of longer-term anthropometric outcomes, assessments of cost effectiveness, acceptability in target populations and potential for implementation in routine service delivery.

CONCLUSION

There is an urgent need for further research on effective obesity prevention interventions for Indigenous children. The findings from the growing body of intervention research focusing on obesity prevention amongst young children from socioeconomically disadvantaged families suggest intervention effects are modest but promising. Further high quality studies with longer term follow up are required.

TRIAL REGISTRATION

PROSPERO Registration no: CRD42013006536.

Association between Obesity and History of Abuse among American Indians in Rural California

OBJECTIVES

To explore factors associated with obesity among American Indians.

METHODS

A cross-sectional survey of American Indian adults (N=459) was conducted at 13 rural reservation sites in California. Participants responded to a survey about their health and wellness perceptions. The Body Mass Index (BMI) was used to assess obesity. A predictive model for BMI was built using a generalized regression model.

RESULTS

Having high blood pressure and having a history of verbal abuse in childhood were significant predictors of higher BMI. Participants with high blood pressure were likely to have 3.2 units of BMI higher on average than those who do not have high blood pressure (p-value <0.0001). Similarly, those with a history of childhood verbal abuse were likely to have 1.9 units higher BMI on average compared to those with no such history. Having a history of diabetes or sexual abuse in childhood trend towards increased BMI, although not statistically significant.

CONCLUSION

Identifying childhood trauma and its impact on adult obesity rates among American Indians provides new avenues for intervention. Efforts to reduce over weight and obesity should include culturally sensitive interventions to ameliorate and repair what is lost through personal violations of stigma, abuse or neglect.

Aboriginal birth cohort (ABC): a prospective cohort study of early life determinants of adiposity and associated risk factors among Aboriginal people in Canada

BACKGROUND

Aboriginal people living in Canada have a high prevalence of obesity, type 2 diabetes, and cardiovascular disease (CVD). To better understand the pre and postnatal influences on the development of adiposity and related cardio-metabolic factors in adult Aboriginal people, we will recruit and follow prospectively Aboriginal pregnant mothers and their children - the Aboriginal Birth Cohort (ABC) study.

METHODS/DESIGN

We aim to recruit 300 Aboriginal pregnant mothers and their newborns from the Six Nations Reserve, and follow them prospectively to age 3 years. Key details of environment and health including maternal nutrition, glucose tolerance, physical activity, and weight gain will be collected. At birth, cord blood and placenta samples will be collected, as well as newborn anthropometric measurements. Mothers and offspring will be followed annually with serial measurements of diet and physical activity, growth trajectory, and adiposity.

DISCUSSION

There is an urgent need to understand maternal and child factors that underlie the early development of adiposity and type 2 diabetes in Aboriginal people. The information generated from this cohort will assist the Six Nations community in developing interventions to prevent early adiposity in Aboriginal children.

Describing the growth and rapid weight gain of urban Australian Aboriginal infants

AIM

The aims of this paper are to describe the growth of urban Australian Aboriginal infants from birth to 24 months of age and to identify the proportion of these infants experiencing rapid weight gain (RWG) and overweight/obesity.

METHODS

The Gudaga Study is a longitudinal birth cohort of 159 Australian Aboriginal children born on the urban fringe of Sydney. Birthweight and length were extracted from hospital data. Children with a birthweight >1500 grams were included in the analysis (n = 157). Weight, length and head circumference were measured at 2-3 weeks and then six-monthly until 24 months of age. Age- and gender-specific Z-scores were determined from the Centers for Disease Control (CDC) 2000 growth charts for weight, length, head circumference and body mass index (BMI). The proportion of children experiencing RWG (an increase in weight-for-age Z-scores ≥0.67 between birth and 12 months) was calculated. The association between RWG and ≥85th CDC percentile for BMI at 24 months was tested using Pearson's χ².

RESULTS

The mean weight of Gudaga infants was less than the CDC mean length-for-age at birth and 2-3 weeks of age but greater than CDC mean length-for-age and weight-for-age at 18 and 24 months of age. Overall, 42 infants (34.4%) experienced RWG, and 45 infants (36.9%) were overweight/obese at 24 months of age. A greater proportion of those who experienced RWG (61.9%) were overweight/obese at 24 months than those who did not experience RWG (23.8%).

CONCLUSION

Our study suggests a concerning proportion of urban Indigenous infants experience RWG and overweight/obesity in early childhood.

A community-based intervention to prevent obesity beginning at birth among American Indian children: study design and rationale for the PTOTS study

Eating and physical activity behaviors associated with adult obesity have early antecedents, yet few studies have focused on obesity prevention interventions targeting very young children. Efforts to prevent obesity beginning at birth seem particularly important in populations at risk for early-onset obesity. National estimates indicate that American Indian (AI) children have higher rates of overweight and obesity than children of other races/ethnicities. The Prevention of Toddler Obesity and Teeth Health Study (PTOTS) is a community-partnered randomized controlled trial designed to prevent obesity beginning at birth in AI children. PTOTS was developed to test the effectiveness of a multi-component intervention designed to: promote breastfeeding, reduce sugar-sweetened beverage consumption, appropriately time the introduction of healthy solid foods, and counsel parents to reduce sedentary lifestyles in their children. A birth cohort of 577 children from five AI tribes is randomized by tribe to either the intervention (three tribes) or the comparison condition (two tribes). The strengths and weaknesses of PTOTS include a focus on a critical growth phase, placement in the community, and intervention at many levels, using a variety of approaches.

The Healthy Children, Strong Families intervention: design and community participation

Healthy Children, Strong Families (HCSF) is a 2-year, community-driven, family-based randomized controlled trial of a healthy lifestyles intervention conducted in partnership with four Wisconsin American Indian tribes. HCSF is composed of 1 year of targeted home visits to deliver nutritional and physical activity curricula. During Year 1, trained community mentors work with 2-5-year-old American Indian children and their primary caregivers to promote goal-based behavior change. During Year 2, intervention families receive monthly newsletters and attend monthly group meetings to participate in activities designed to reinforce and sustain changes made in Year 1. Control families receive only curricula materials during Year 1 and monthly newsletters during Year 2. Each of the two arms of the study comprises 60 families. Primary outcomes are decreased child body mass index (BMI) z-score and decreased primary caregiver BMI. Secondary outcomes include: increased fruit/vegetable consumption, decreased TV viewing, increased physical activity, decreased soda/sweetened drink consumption, improved primary caregiver biochemical indices, and increased primary caregiver self-efficacy to adopt healthy behaviors. Using community-based participatory research and our history of university-tribal partnerships, the community and academic researchers jointly designed this randomized trial. This article describes the study design and data collection strategies, including outcome measures, with emphasis on the communities' input in all aspects of the research.

Race/Ethnicity, Obesity, and Related Cardio-Metabolic Risk Factors: A Life-Course Perspective

The adoption of health behaviors characterized by minimal energy expenditure and overconsumption of energy has led to cardiometabolic risk factors in pregnancy, childhood, and youth, all of which increase the prevalence of cardiovascular disease in adulthood. The propensity to develop abdominal obesity and cardiometabolic risk factors appears to disproportionally affect non-white ethnic groups. While the majority of observational research has been conducted in populations of European origin, studies in non-white ethnic groups across the life-course are underway and there is evidence that unique ethnic-specific differences exist. This review will focus on the life-course determinants of obesity and its related cardio-metabolic risk factors among diverse ethnic groups including people of Afro-Caribbean origin, South Asian, East Asian, and indigenous ancestry.

Overweight and obesity among North American Indian infants, children, and youth

The frequency of overweight and obesity among North American Indian children and youth exceeds that of other ethnic groups in the United States. This observation is based on studies using body mass index as the primary measure of overweight and obesity. In the mid-20th century, there were regional differences among North American Indian groups in sub-adults' size and shape and only a few Southwestern groups were characterized by high rates of overweight and obesity. In most populations, the high prevalence of overweight and obesity developed in the last decades of the 20th century. Childhood obesity may begin early in life as many studies report higher birth weights and greater weight-for-height in the preschool years. Contributing factors include higher maternal weights, a nutritional transition from locally caught or raised foods to store bought items, psychosocial stress associated with threats to cultural identity and national sovereignty, and exposure to obesogenic pollutants, all associated to some degree with poverty. Obesity is part of the profile of poor health among Native Americans in the US and Canada, and contributes to woefully high rates of diabetes, cardiovascular disease, and early mortality. Interventions that are culturally appropriate are needed to reduce weights at all points in the lifespan.

Greater impact of melanocortin-4 receptor deficiency on rates of growth and risk of type 2 diabetes during childhood compared with adulthood in Pima Indians

Features of melanocortin-4 receptor (MC4R) deficiency have been observed to be more pronounced in childhood. Longitudinal data from a population-based study were used to separate the phenotypic effects of MC4R deficiency during childhood and adulthood. The MC4R exon was sequenced in 6,760 individuals of predominantly Pima Indian heritage, and discovered mutations were functionally assessed in vitro. Effects on BMI, height, and slope of BMI change were assessed during childhood (ages 5-20 years) and adulthood (ages 20-45 years). Six mutations affecting MC4R function, including three that may be private to Pima Indians, were found in 159 individuals (2.4%). The slope of BMI increase was greater in individuals carrying an MC4R mutation compared with noncarriers during childhood but not during adulthood. The final adult height obtained was higher in individuals with MC4R deficiency. There was an increased risk for developing type 2 diabetes in individuals with a defective MC4R during childhood and adulthood, but this was only independent of BMI in childhood. The greater rates of body mass accumulation and risk of type 2 diabetes before the age of 20 years in individuals with MC4R deficiency indicate that the effects of these mutations are more apparent during the active growth of childhood.

The TOTS community intervention to prevent overweight in American Indian toddlers beginning at birth: a feasibility and efficacy study

Excess weight gain in American Indian/Alaskan native (AI/AN) children is a public health concern. This study tested (1) the feasibility of delivering community-wide interventions, alone or in combination with family-based interventions, to promote breastfeeding and reduce the consumption of sugar-sweetened beverages; and (2) whether these interventions decrease Body Mass Index (BMI)-Z scores in children 18-24 months of age. Three AI/AN tribes were randomly assigned to two active interventions; a community-wide intervention alone (tribe A; n = 63 families) or community-wide intervention containing a family component (tribes B and C; n = 142 families). Tribal staff and the research team designed community-tailored interventions and trained community health workers to deliver the family intervention through home visits. Feasibility and acceptability of the intervention and BMI-Z scores at 18-24 months were compared between tribe A and tribes B & C combined using a separate sample pretest, posttest design. Eighty-six percent of enrolled families completed the study. Breastfeeding initiation and 6-month duration increased 14 and 15%, respectively, in all tribes compared to national rates for American Indians. Breastfeeding at 12 months was comparable to national data. Parents expressed confidence in their ability to curtail family consumption of sugar-sweetened beverages. Compared to a pretest sample of children of a similar age 2 years before the study begun, BMI-Z scores increased in all tribes. However, the increase was less in tribes B & C compared to tribe A (-0.75, P = 0.016). Family, plus community-wide interventions to increase breastfeeding and curtail sugar-sweetened beverages attenuate BMI rise in AI/AN toddlers more than community-wide interventions alone.

Period-specific growth, overweight and modification by breastfeeding in the GINI and LISA birth cohorts up to age 6 years

Children's weight/growth development is age-specific and may be influenced by breastfeeding. We therefore assessed velocities of weight, length, body-mass-index and overweight/obesity development from birth up to age 6 years overall and in relation to breastfeeding. The method of this study is based on pooled data of the birth-cohorts GINI-plus and LISA-plus and follows 7,643 healthy full-term neonates in four study-centers in Germany. Up to nine anthropometric measurements are available. Overweight/obesity is percentile-defined according to WHO-Child-Growth-Standards. Fully-breastfed is defined as breastfed for at least 4 months. Piecewise-linear-random-coefficient-models were applied to assess growth trajectories and velocities between 0-3, 3-6, 6-12, 12-24 and beyond 24th months. Velocities for weight-, length- and BMI-development are highest in the first 3 months after birth and diminish, with differing pace, in the periods that follow. For overweight and obesity, peak-velocities are estimated in periods 6-12 and 3-6 months. The difference in the velocity of weight gain for breastfed vs. other children is -18 g/month in the first 3 month, -93 g/month between month 3 and 6, -14 g/month between month 6 and 12 and -3 g/month beyond the 24th month. Velocities in length are not different between breastfed and non-breastfed children. Over time, a slightly lower risk (difference < 2%) of being overweight was estimated for breastfed children, after adjustment for study-center, socio-economic-status and maternal smoking in pregnancy. Infants fully-breastfed gain less weight, but grow equally in length in the first 12 months of life versus mixed or formula-fed children. The protective effect of breastfeeding on becoming overweight is related to its weight-velocity-modifying-effect in early infancy.

Association of weight gain in infancy and early childhood with metabolic risk in young adults

CONTEXT

Early postnatal life has been suggested as an important window during which risks for long-term health may be influenced.

OBJECTIVE

The aim of this study was to examine the independent associations between weight gain during infancy (0-6 months) and early childhood (3-6 yr) with components of the metabolic syndrome in young adults.

DESIGN

This was a prospective cohort study (The Stockholm Weight Development Study).

SETTING

The study was conducted in a general community.

PARTICIPANTS

Subjects included 128 (54 males) singletons, followed from birth to 17 yr.

MAIN OUTCOME MEASURE

None of these young adults met the full criteria for the metabolic syndrome. We therefore calculated a continuous clustered metabolic risk score by averaging the standardized values of the following components: waist circumference, blood pressure, fasting triglycerides, high-density lipoprotein cholesterol, glucose, and insulin level.

RESULTS

Clustered metabolic risk at age 17 yr was predicted by weight gain during infancy (standardized beta = 0.16; P < 0.0001) but not during early childhood (standardized beta = 0.10; P = 0.23), adjusted for birth weight, gestational age, current height, maternal fat mass, and socioeconomic status at age 17 yr. Further adjustment for current fat mass and weight gain during childhood did not alter the significant association between infancy weight gain with the metabolic risk score (standardized beta = 0.20; P = 0.007).

CONCLUSIONS

Rapid weight gain during infancy (0-6 months) but not during early childhood (3-6 yr) predicted clustered metabolic risk at age 17 yr. Early interventions to moderate rapid weight gain even at very young ages may help to reduce adult cardiovascular disease risks.

Height, weight, and body mass index among Akwesasne Mohawk youth

Information on the growth of contemporary Native American adolescents is limited. A few studies have shown that Native Americans have growth patterns that may differ from U.S. reference values. We describe basic anthropometric characteristics (height and weight) of Mohawk youth between the ages of 10.0 and 16.99 years from the Akwesasne Mohawk Nation. Body mass index (BMI) was calculated. Mean height of Akwesasne Mohawk youth approximates the 50th percentile of reference values as determined by the 2000 Center for Disease Control and Prevention (CDC) growth charts. At every age, weight means of males approximate or exceed the 90th percentile and all mean weights of females approximate the 85th percentile. Akwesasne males are significantly taller than females from age 14 on and significantly heavier at ages 14 and 16. All age-specific BMI means for males are at or above the 90th percentile and females' means are at or above the 85th. The potential for long-term health effects associated with being overweight has implications for the future health of young Native Americans.

Early growth in offspring of diabetic mothers

OBJECTIVE

By age 5 years, offspring of diabetic mothers (ODMs) are heavier and have altered glucose metabolism compared with offspring of mothers without diabetes (non-DMs). This study evaluates the growth pattern of ODMs before the age of 5 years.

RESEARCH DESIGN AND METHODS

Anthropometric measures (z scores) from birth, 1.5 years, and 7.7 years in Pima Indian children were compared by maternal diabetes status.

RESULTS

After adjustment for earlier gestational age at delivery (37.8 vs. 39.3 weeks, P < 0.01), ODMs were heavier at birth (z score birth weight 0.49 vs. -0.04, P < 0.01) than non-DMs. At age 1.5 years, ODMs were shorter than the non-DMs (z score = -0.24 vs. 0.12, P < 0.01) but their weight and relative weight (RW; weight adjusted for age, sex, and length or height) were similar. From birth to 1.5 years, ODMs showed significant "catch down" of weight compared with non-DMs (change in weight z score from birth to 1.5 years of ODMs and non-DMs was -0.56 and 0.12, respectively, P < 0.01). By age 7.7 years, ODMs were heavier (weight z score 0.89 vs. -0.07, P < 0.01) but had similar height as non-DMs. Differences in glucose and insulin concentrations at age 7.7 years were dependent on RW.

CONCLUSIONS

ODMs had a dramatically different growth pattern from that of non-DMs. Gestational age-adjusted birth weight was higher. During the first 1.5 postnatal years, the change in weight z score and attained height were reduced. Subsequently, height caught up to that of non-DMs, while weight gain greatly exceeded that of non-DMs.

Pancreatic polypeptide is involved in the regulation of body weight in pima Indian male subjects

Pancreatic polypeptide (PP) is released from the pancreas in response to a meal. In humans, low-circulating PP levels have been observed in obesity, and administration of pharmacological doses of PP has been shown to decrease food intake. The aim of the present study was to investigate whether low circulating PP is associated with weight gain in Pima Indians. Plasma PP concentrations were measured after an overnight fast and 30 min after a standardized mixed meal in 33 nondiabetic male subjects who had a follow-up visit 4.9 +/- 2.5 years later. Cross-sectionally, fasting and postprandial PP levels were negatively associated with body size and adiposity. Prospectively, the change in PP response to the meal was negatively associated with the change in body weight (r = -0.53, P = 0.002). In contrast, a high fasting PP level was positively associated with change in body weight (r = 0.45, P = 0.009). In conclusion, our results provide evidence that, even within the physiological range, PP contributes to the regulation of energy balance in humans. However this contribution appears to be more complex than anticipated because of the opposite effect of fasting and postprandial PP on the risk of future weight gain.

Beverage consumption and risk of obesity among Native Americans in Arizona

Native Americans face some of the highest rates of obesity and diabetes in the world. Despite numerous education programs to reduce obesity among Native Americans, little attention has been paid to reducing fructose, particularly in the form of high-fructose corn syrup in beverages. Considerable data indicate that energy from beverages does not displace energy from other foods throughout the day, often leading to energy imbalance, and numerous studies have documented that beverages are a leading contributor to energy intakes among Native Americans. Prevention programs that target pregnant women and parents of infants and very young children are necessary to halt the epidemic of obesity among Native Americans; one approach may be by promoting sugar-free beverages.

Distribution of adipose tissue in the newborn

Regional differences in adipose tissue distribution are associated with differences in adipocyte metabolism and obesity-related morbidities. Intrauterine growth restriction appears to place individuals at greater risk of obesity associated morbidities in later life. Despite this, little is known regarding the quantity and distribution of adipose tissue in infants during early development. The aim of this study was to compare total and regional adipose tissue content in appropriate-for-gestational-age (AGA) and growth-restricted (GR) newborn infants born at or near term. Whole body adipose tissue magnetic resonance imaging (MRI) was performed as soon as possible after birth. Total and regional adipose tissue depots were quantified. A total of 35 infants (10 GR; 25 AGA) were studied. Mean (SD) total percentage adipose tissue was lower in GR infants than AGA infants [GR: 17.70% (2.17); AGA: 23.40% (3.85); p = 0.003]. This difference arose from differences in subcutaneous adipose tissue mass [mean (SD) percentage subcutaneous adipose tissue mass, GR: 16.13% (2.20); AGA: 21.44% (3.81); p = 0.004], but not intra-abdominal adipose tissue mass [mean (SD) percentage intra-abdominal adipose tissue, GR: 0.42% (0.22); AGA: 0.61% (0.31); p = 0.45]. In contrast to subcutaneous adipose tissue, intra-abdominal adipose tissue is not reduced in infants with intrauterine growth restriction. This suggests that subcutaneous and intra-abdominal adipose tissue compartments may be under different regulatory control during intrauterine life.

Obesity in American-Indian children: prevalence, consequences, and prevention

BACKGROUND

American Indians of all ages and both sexes have a high prevalence of obesity. The health risks associated with obesity are numerous and include Type 2 diabetes mellitus, hypertension, dyslipidemia, and respiratory problems. Obesity has become a major health problem in American Indians only in the past few generations and it is believed to be associated with the relative abundance of high-fat, high-calorie foods and the rapid change from active to sedentary lifestyles.

METHODS

The authors reviewed selected literature on prevalence of obesity in American-Indian children, and health consequences of obesity.

RESULTS

Obesity is now one of the most serious public health problems facing American-Indian children, and it has grave implications for the immediate and long-term health of American-Indian youth. Unless this pattern is reversed, American-Indian populations will be burdened by an increased incidence of chronic diseases. Intervention studies are urgently needed in American-Indian communities to develop and test effective strategies for obesity prevention and treatment.

CONCLUSIONS

To be effective, educational and environmental interventions must be developed with full participation of the American-Indian communities.

Obesity prevention in preschool native-american children: a pilot study using home visiting

OBJECTIVE

To determine whether maternal participation in an obesity prevention plus parenting support (OPPS) intervention would reduce the prevalence of obesity in high-risk Native-American children when compared with a parenting support (PS)-only intervention.

RESEARCH METHODS AND PROCEDURES

Forty-three mother/child pairs were recruited to participate. Mothers were 26.5 +/- 5 years old with a mean BMI of 29.9 +/- 3 kg/m(2). Children (23 males) were 22 +/- 8 months old with mean weight-for-height z (WHZ) scores of 0.73 +/- 1.4. Mothers were randomly assigned to a 16-week OPPS intervention or PS alone. The intervention was delivered one-on-one in homes by an indigenous peer educator. Baseline and week 16 assessments included weight and height (WHZ score and weight-for-height percentile for children), dietary intake (3-day food records), physical activity (measured by accelerometers), parental feeding style (Child Feeding Questionnaire), and maternal outcome expectations, self-efficacy, and intention to change diet and exercise behaviors.

RESULTS

Changes in WHZ scores showed a trend toward significance, with WHZ scores decreasing in the PS condition and increasing among the OPPS group (-0.27 +/- 1.1 vs. 0.31 +/- 1.1, p = 0.06). Children in the OPPS condition also significantly decreased energy intake (-316 +/- 835 kcal/d vs. 197 +/- 608 kcal/d, p < 0.05). Scores on the restriction subscale of the Child Feeding Questionnaire decreased significantly in the OPPS condition (-0.22+/- 0.42 vs. 0.08+/- 0.63, p < 0.05), indicating that mothers in the OPPS group were engaging in less restrictive child feeding practices over time.

DISCUSSION

A home-visiting program focused on changing lifestyle behaviors and improving parenting skills showed promise for obesity prevention in high-risk Native-American children.