Secular changes in physical growth and obesity among southwestern American Indian children over four decades

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.

Youth-onset type 2 diabetes mellitus: an urgent challenge

The incidence and prevalence of youth-onset type 2 diabetes mellitus (T2DM) and its complications are increasing worldwide. Youth-onset T2DM has been reported in all racial and ethnic groups, but Indigenous peoples and people of colour are disproportionately affected. People with youth-onset T2DM often have a more aggressive clinical course than those with adult-onset T2DM or those with type 1 diabetes mellitus. Moreover, the available treatment options for children and adolescents with T2DM are more limited than for adult patients. Intermediate complications of youth-onset T2DM, such as increased albuminuria, often develop in late childhood or early adulthood, and end-stage complications, including kidney failure, develop in mid-life. The increasing frequency, earlier onset and greater severity of childhood obesity in the past 50 years together with increasingly sedentary lifestyles and an increasing frequency of intrauterine exposure to diabetes are important drivers of the epidemic of youth-onset T2DM. The particularly high risk of the disease in historically disadvantaged populations suggests an important contribution of social and environmental factors, including limited access to high-quality health care, healthy food choices and opportunities for physical activity as well as exposure to stressors including systemic racism and environmental pollutants. Understanding the mechanisms that underlie the development and aggressive clinical course of youth-onset T2DM is key to identifying successful prevention and management strategies.

Changes in the adiposity level and prevalence of overweight/obesity among children from Kraków (Poland) within the last decade (from 2010 to 2020)

The aim of this study was to assess the changes in the prevalence of overweight, obesity and high adiposity in children and adolescents from Krakow (Poland), between the years 2010 and 2020. Two cross-sectional series of anthropometric measurements were carried out in 2010 and 2020. Analysed characteristics included: body height and weight, BMI (Body Mass Index), body adiposity (%BF). The subjects were categorised according to their BMI (underweight, normal weight, overweight, obesity), as well as %BF (low, normal, high body fat).The research was conducted in randomly selected primary schools in Krakow (Poland). Studied cohorts (8-15 years of age), which represented four of the traditional residential districts: Śródmieście, Podgórze, Krowodrza and Nowa Huta. Among the girls, there was a negative secular trend regarding the prevalence of underweight and obesity. On the other hand, there also was a positive trend concerning the prevalence of overweight and low and high body fat. In boys, there was a negative secular trend regarding the prevalence of underweight and low adiposity. There was also a generally positive secular trend regarding the prevalence of overweight, obesity as well as high adiposity in boys. The findings of this study are particularly significant because detailed knowledge of the prevalence of overweight/obesity in childhood and adolescence is crucial for the future health of entire populations. Further studies should also take into account the levels of physical fitness and activity of the examined population.

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.

Pima Indian Contributions to Our Understanding of Diabetic Kidney Disease

Prospective studies in informative populations are crucial to increasing our knowledge of disease. In this perspective, we describe a half century of studies in an American Indian population that transformed our understanding of kidney disease in type 2 diabetes, now recognized as the leading cause of kidney failure worldwide. Serial examinations conducted for many years that included the collection of data and samples across multiple domains captured an unprecedented volume of clinical, physiologic, morphometric, genomic, and transcriptomic data. This work permitted us to extensively characterize the course and determinants of diabetic kidney disease, its pathophysiologic underpinnings, and important secular trends of urgent concern to populations worldwide, including the emergence of youth-onset type 2 diabetes and its effect on development of diabetic kidney disease in midlife. By combining these data using the tools of integrative biology, we are developing new mechanistic insights into the development and progression of diabetic kidney disease in type 2 diabetes. These insights have already contributed to the identification and successful therapeutic targeting of a novel pathway in DKD. We anticipate that this work will continue to expand our understanding of this complex disease and influence its management in the coming years.

Exchanging fluids The sociocultural implications of microbial, cultural, and ethnic admixture in Latin America

Knowledge of evolutionary influences on patterns of human mating, social interactions, and differential health is increasing, yet these insights have rarely been applied to historical analyses of human population dynamics. The genetic and evolutionary forces behind biases in interethnic mating and in the health of individuals of different ethnic groups in Latin America and the Caribbean since the European colonization of America are still largely ignored. We discuss how historical and contemporary sociocultural interactions and practices are strongly influenced by population-level evolutionary forces. Specifically, we discuss the historical implications of functional (de facto) polygyny, sex-biased admixture, and assortative mating in Latin America. We propose that these three evolutionary mechanisms influenced mating patterns, shaping the genetic and cultural landscape across Latin America and the Caribbean. Further, we discuss how genetic differences between the original populations that migrated at different times into Latin America contributed to their accommodation to and survival in the different local ecologies and interethnic interactions. Relevant medical and social implications follow from the genetic and cultural changes reviewed.

Weight tracking in childhood and adolescence and type 2 diabetes risk

AIMS/HYPOTHESIS

The aim of this work was to examine the associations of average weight and weight velocity in three growth periods from birth through adolescence with type 2 diabetes incidence.

METHODS

Child participants were selected from a 43 year longitudinal study of American Indians to represent three growth periods: pre-adolescence (birth to ~8 years); early adolescence (~8 to ~13 years); and late adolescence (~13 to ~18 years). Age-, sex- and height-standardised weight z score mean and weight z score velocity (change/year) were computed for each period. Participants were followed for up to 25 years from the end of each growth period until they developed diabetes. Associations of weight z score mean or weight z score velocity with diabetes incidence were determined with sex-, birth date- and maternal diabetes-adjusted Poisson regression models.

RESULTS

Among 2100 participants representing the pre-adolescence growth period, 1558 representing the early adolescence period and 1418 representing the late adolescence period, there were 290, 315 and 380 incident diabetes cases, respectively. During the first 10 years of follow-up, the diabetes incidence rate ratio (95% CI) was 1.72 (1.40, 2.11)/SD of log₁₀ weight z score mean in pre-adolescence, 2.09 (1.68, 2.60)/SD of log₁₀ weight z score mean in early adolescence and 1.85 (1.58, 2.17)/SD of log₁₀ weight z score mean in late adolescence. The diabetes incidence rate ratio (95% CI) was 1.79 (1.49, 2.17)/SD of log₁₀ weight z score velocity in pre-adolescence, 1.13 (0.91, 1.41)/SD of log₁₀ weight z score velocity in early adolescence and 1.29 (1.09, 1.51)/SD of log₁₀ weight z score velocity in late adolescence. There were strong correlations in the weight z score means and weak correlations in the weight z score velocities between successive periods.

CONCLUSIONS/INTERPRETATION

Higher weight and accelerated weight gain in all growth periods associate with increased type 2 diabetes risk. Importantly, higher weight and greater weight velocity during pre-adolescence jointly associate with the highest type 2 diabetes risk. Graphical abstract.

Impact of text message-based intervention for weight control and health-promoting lifestyle behaviors of overweight and obese children

BACKGROUND AND AIM

Little information is available on the use of text messages through mobile phones to address overweight/obesity in children. This study aims to evaluate the impact of a text message-based intervention for weight control and health-promoting lifestyle behaviors of overweight/obese children.

MATERIALS AND METHODS

This quasi-experimental study was conducted among overweight/obese school students. Data on sociodemographic, dietary intake, sleep, sedentary behavior, physical activity (PA), and anthropometry were collected before and after the intervention. Weight and height were examined according to the standard protocols. The intervention was consisted of tailored messages for weight control and healthy lifestyle, including diet, PA, sedentary behavior, and sleep. Child attitude and his practice were asked before and after the intervention. The paired t-test was performed to compare means of continuous variables before and after the intervention for normal distribution data. The Wilcoxon test was also used for nonnormal data.

RESULTS

A total of 71 boy students were included in the study (62% obese). The mean age was 10.07 years. The means of attitude score for PA, nutrition, and sleep after intervention were greater than before it, but it was significant only for PA. The mean of nighttime sleep duration of students after the intervention was significantly less. Furthermore, unhealthy score decreases after the intervention.

CONCLUSION

Three-month lifestyle intervention as text messages had positive effects on the nutritional intake of obese children and their attitudes toward PA, but no effect on child body mass index.

Implementation of the Navajo fruit and vegetable prescription programme to improve access to healthy foods in a rural food desert

OBJECTIVE

To utilise a community-based participatory approach in the design and implementation of an intervention targeting diet-related health problems on Navajo Nation.

DESIGN

A dual strategy approach of community needs/assets assessment and engagement of cross-sectorial partners in programme design with systematic cyclical feedback for programme modifications.

SETTING

Navajo Nation, USA.

PARTICIPANTS

Navajo families with individuals meeting criteria for programme enrolment. Participant enrolment increased with iterative cycles.

RESULTS

The Navajo Fruit and Vegetable Prescription (FVRx) Programme.

CONCLUSIONS

A broad, community-driven and culturally relevant programme design has resulted in a programme able to maintain core programmatic principles, while also allowing for flexible adaptation to changing needs.

Changes in the prevalence of overweight/obesity and adiposity among pre-school children in Kraków, Poland, from 2008 to 2018

Socioeconomic changes occurring over time influence the lifestyle choices of a population, and these can significantly affect children’s body weight and composition. The aim of this study was to assess the changes in prevalence of overweight, obesity and adiposity in pre-school children in Poland between 2008 and 2018. Body height, body weight and subscapular and triceps skinfolds were measured in 2167 children aged 3–7 years from Kraków. Body mass index and adiposity (percentage body fat, %BF) were calculated for the children, who were then categorized as underweight, normal weight, overweight or obese according to Cole’s cut-off points. Adiposity was categorized according to the z-scores for %BF as low (<−1), normal (−1 to 1) or high (>1). Differences between cohorts were analysed using the chi-squared test. Only the decrease in the prevalence of obesity in 5-year-old girls was found to be statistically significant. However, some overall tendencies were noted. Decreases in the prevalence of underweight, overweight and obesity were observed for both sexes, as well as in the incidence of high adiposity in boys and low adiposity in girls. Increases in the prevalence of high adiposity in girls and low adiposity in boys were also noted. There was no significant change in the prevalence of overweight and obesity among pre-school children over the study decade, and the visible tendencies included decreases in the prevalence of excess body weight and adiposity as well as underweight and low body fat. Also, the visible trends in adiposity were mostly negative. Further studies should, however, also consider the levels of physical fitness and activity of children, as these have a crucial influence on the measured characteristics.

Trends in height, weight, BMI, skinfolds, and measures of overweight and obesity from 1979 through 1999 among American Indian Youth: The Akwesasne Mohawk

BACKGROUND/OBJECTIVES

Information on recent changes in overweight, obesity, and adiposity among American Indians is scarce. To assess changes in size and adiposity among American Indian youth, data from two samples of Akwesasne Mohawk youth, were compared.

SUBJECTS/METHODS

Both project 1, conducted in 1979 (n = 75) and Project 2, conducted between 1996 and 1999 (n = 206), sampled youth 10-14 years of age from the Akwesasne Mohawk Reservation (aka St. Regis) that borders New York state, and Ontario and Quebec provinces. Heights, weights, and skinfold thicknesses were converted to z-scores using CDC reference values. BMI status was calculated in terms of WHO age-specific cutoffs and CDC cutoffs.

RESULTS

z-Scores for heights differed little between projects. The between-project difference in weight z-score is twice the between-project z-score difference for height. Differences among males are larger and more often significant. Triceps and subscapular skinfold thickness are significantly greater in Project 2. The rate of overweight and obesity combined, increased 3.3-fold. In multiple regression analyses with sex, height, and age in the model, project is a significant predictor of weight and skinfolds.

CONCLUSIONS

Weight and adiposity have increased substantially from 1979 to 1996-99. Overweight and obesity became significantly more common. Given the increase in adiposity, these youth may be facing significant health risks as adults in terms of cardiovascular disease, cancer, and type II diabetes unless weight and adiposity is reduced.

Targeting risk factors for type 2 diabetes in American Indian youth: the Tribal Turning Point pilot study

BACKGROUND

American Indian (AI) youth are at high risk for type 2 diabetes.

OBJECTIVES

To partner with Eastern Band of Cherokee Indians and Navajo Nation to develop a culturally sensitive behavioural intervention for youth (Tribal Turning Point; TTP) and assess feasibility in an 8-month randomized pilot study.

METHODS

We enrolled 62 overweight/obese AI children (7-10 years) who participated with ≥1 parent/primary caregiver. Intervention participants (n = 29) attended 12 group classes and five individual sessions. Control participants (n = 33) attended three health and safety group sessions. We analysed group differences for changes in anthropometrics (BMI, BMI z-score, waist circumference), cardiometabolic (insulin, glucose, blood pressure) and behavioural (physical activity and dietary self-efficacy) outcomes.

RESULTS

Study retention was 97%, and intervention group attendance averaged 84%. We observed significant treatment effects (p = 0.02) for BMI and BMI z-score: BMI increased in control (+1.0 kg m^-2 , p < 0.001) but not intervention participants (+0.3 kg m^-2 , p = 0.13); BMI z-score decreased in intervention (-0.17, p = 0.004) but not control participants (0.01, p = 0.82). There were no treatment effects for cardiometabolic or behavioural outcomes.

CONCLUSIONS

We demonstrated that a behavioural intervention is feasible to deliver and improved obesity measures in AI youth. Future work should evaluate TTP for effectiveness, sustainability and long-term impact in expanded tribal settings.

Growth Tracking in Severely Obese or Underweight Children

OBJECTIVES

To illustrate the difficulties in optimal growth monitoring of children with severe obesity or underweight by using the Centers for Disease Control and Prevention (CDC) 2000 age- and sex-specific BMI percentile growth charts. We also aimed to examine the utility of a new modified CDC BMI z score chart to monitor growth in children with normal and extreme BMI percentiles by using real-life clinical scenarios.

METHODS

Modified BMI z score charts were created by using the 2000 CDC algorithm. Three cases of children with extreme BMI values and abnormal growth patterns were plotted by using the standard CDC 2000 clinical growth chart, the modified BMI z score chart, and the CDC BMI percentile chart, modified to include the percentage of the 95th percentile (%BMI_p95) curves.

RESULTS

Children with severe obesity could not be plotted on the standard CDC BMI percentile chart because their BMI points lay above the chart cutoff. Children with a low BMI (<3%) were also difficult to track on the standard BMI percentile chart. The addition of the %BMI_p95 scale to the standard BMI percentile chart allowed tracking of severely obese children; however, it did not address severely underweight children and required a change of units within the chart when transitioning from normal to obese BMIs. The modified BMI z score chart allowed uniform tracking.

CONCLUSIONS

The modified CDC z score chart is suitable for growth tracking of children with normal and extreme growth patterns; the measures correlate well with the %BMI_p95, and the chart can be incorporated easily into existing electronic health record systems for clinical use.