Birthweight and early-onset type 2 diabetes in American Indians: differential effects in adolescents and young adults and additive effects of genotype, BMI and maternal diabetes

Barriers to implementing good nutrition in pregnancy and early childhood: Creating equitable national solutions

Exposure to deleterious stressors in early life, such as poor nutrition, underlies most adult-onset chronic diseases. As rates of chronic disease continue to climb in the United States, a focus on good nutrition before and during pregnancy, lactation, and early childhood provides a potential opportunity to reverse this trend. This report provides an overview of nutrition investigations in pregnancy and early childhood and addresses racial disparities and health outcomes, current national guidelines, and barriers to achieving adequate nutrition in pregnant individuals and children. Current national policies and community interventions to improve nutrition, as well as the current state of nutrition education among healthcare professionals and students, are discussed. Major gaps in knowledge and implementation of nutrition practices during pregnancy and early childhood were identified and action goals were constructed. The action goals are intended to guide the development and implementation of critical nutritional strategies that bridge these gaps. Such goals create a national blueprint for improving the health of mothers and children by promoting long-term developmental outcomes that improve the overall health of the US population.

Low birthweight is associated with a higher incidence of type 2 diabetes over two decades independent of adult BMI and genetic predisposition

AIMS/HYPOTHESIS

Low birthweight is a risk factor for type 2 diabetes. Most previous studies are based on cross-sectional prevalence data, not designed to study the timing of onset of type 2 diabetes in relation to birthweight. We aimed to examine associations of birthweight with age-specific incidence rate of type 2 diabetes in middle-aged to older adults over two decades.

METHODS

Adults aged 30-60 years enrolled in the Danish Inter99 cohort in 1999-2001 (baseline examination), with information on birthweight from original birth records from 1939-1971 and without diabetes at baseline, were eligible. Birth records were linked with individual-level data on age at diabetes diagnosis and key covariates. Incidence rates of type 2 diabetes as a function of age, sex and birthweight were modelled using Poisson regression, adjusting for prematurity status at birth, parity, polygenic scores for birthweight and type 2 diabetes, maternal and paternal diabetes history, socioeconomic status and adult BMI.

RESULTS

In 4590 participants there were 492 incident type 2 diabetes cases during a mean follow-up of 19 years. Type 2 diabetes incidence rate increased with age, was higher in male participants, and decreased with increasing birthweight (incidence rate ratio [95% CI per 1 kg increase in birthweight] 0.60 [0.48, 0.75]). The inverse association of birthweight with type 2 diabetes incidence was statistically significant across all models and in sensitivity analysis.

CONCLUSIONS/INTERPRETATION

A lower birthweight was associated with increased risk of developing type 2 diabetes independent of adult BMI and genetic risk of type 2 diabetes and birthweight.

Maternal glucose intolerance during pregnancy affects offspring POMC expression and results in adult metabolic alterations in a sex-dependent manner

Introduction

Gestational diabetes (GDM) is associated with negative outcomes in mothers and their offspring, including greater risks of macrosomia at birth and the development of metabolic disorders. While these outcomes are well-established, the mechanisms by which this increased metabolic vulnerability is conferred on the offspring are comparatively lacking. One proposed mechanism is that maternal glycemic dysregulation alters the development of the hypothalamic regions related to metabolism and energy balance.

Methods

To investigate this possibility, in this study, we first examined the effects of STZ-induced maternal glucose intolerance on the offspring on pregnancy day (PD) 19, and, in a second experiment, in early adulthood (postnatal day (PND) 60). Whether effects would be influenced by sex, or exposure of offspring to a high-fat diet was also investigated. The impact of maternal STZ treatment on POMC neuron number in the ARC of offspring at both time points was also examined.

Results

As expected, STZ administration on PD 7 decreased maternal glucose tolerance, and increased risk for macrosomia, and loss of pups at birth. Offspring of STZ-treated mothers were also more vulnerable to developing metabolic impairments in adulthood. These were accompanied by sex-specific effects of maternal STZ treatment in the offspring, including fewer POMC neurons in the ARC of female but not male infants in late pregnancy and a higher number of POMC neurons in the ARC of both male and female adult offspring of STZ-treated dams, which was exacerbated in females exposed to a high-fat diet after weaning.

Discussion

This work suggests that maternal hyperglycemia induced by STZ treatment, in combination with early-life exposure to an obesogenic diet, leads to adult metabolic alterations that correlate with the increased hypothalamic expression of POMC, showing that maternal glycemic dysregulation can impact the development of hypothalamic circuits regulating energy state with a stronger impact on female offspring.

The utility of a type 2 diabetes polygenic score in addition to clinical variables for prediction of type 2 diabetes incidence in birth, youth and adult cohorts in an Indigenous study population

AIMS/HYPOTHESIS

There is limited information on how polygenic scores (PSs), based on variants from genome-wide association studies (GWASs) of type 2 diabetes, add to clinical variables in predicting type 2 diabetes incidence, particularly in non-European-ancestry populations.

METHODS

For participants in a longitudinal study in an Indigenous population from the Southwestern USA with high type 2 diabetes prevalence, we analysed ten constructions of PS using publicly available GWAS summary statistics. Type 2 diabetes incidence was examined in three cohorts of individuals without diabetes at baseline. The adult cohort, 2333 participants followed from age ≥20 years, had 640 type 2 diabetes cases. The youth cohort included 2229 participants followed from age 5-19 years (228 cases). The birth cohort included 2894 participants followed from birth (438 cases). We assessed contributions of PSs and clinical variables in predicting type 2 diabetes incidence.

RESULTS

Of the ten PS constructions, a PS using 293 genome-wide significant variants from a large type 2 diabetes GWAS meta-analysis in European-ancestry populations performed best. In the adult cohort, the AUC of the receiver operating characteristic curve for clinical variables for prediction of incident type 2 diabetes was 0.728; with the PS, 0.735. The PS's HR was 1.27 per SD (p=1.6 × 10-8; 95% CI 1.17, 1.38). In youth, corresponding AUCs were 0.805 and 0.812, with HR 1.49 (p=4.3 × 10-8; 95% CI 1.29, 1.72). In the birth cohort, AUCs were 0.614 and 0.685, with HR 1.48 (p=2.8 × 10-16; 95% CI 1.35, 1.63). To further assess the potential impact of including PS for assessing individual risk, net reclassification improvement (NRI) was calculated: NRI for the PS was 0.270, 0.268 and 0.362 for adult, youth and birth cohorts, respectively. For comparison, NRI for HbA1c was 0.267 and 0.173 for adult and youth cohorts, respectively. In decision curve analyses across all cohorts, the net benefit of including the PS in addition to clinical variables was most pronounced at moderately stringent threshold probability values for instituting a preventive intervention.

CONCLUSIONS/INTERPRETATION

This study demonstrates that a European-derived PS contributes significantly to prediction of type 2 diabetes incidence in addition to information provided by clinical variables in this Indigenous study population. Discriminatory power of the PS was similar to that of other commonly measured clinical variables (e.g. HbA1c). Including type 2 diabetes PS in addition to clinical variables may be clinically beneficial for identifying individuals at higher risk for the disease, especially at younger ages.

Low and insufficient birth weights as important factors of developmental stages of type 2 diabetes: Intergenerational Limache Cohort study

BACKGROUND & AIMS

This study aimed to investigate the association of birth weight with developmental stages of Type 2 Diabetes among Chilean young adults.

METHODS

A probabilistic sample of 1947 individuals (22-28 years) that belong to two birth cohorts (cohort 1: participants born in 1974-1978, cohort 2: participants born in 1988-1992). Multivariable logistic regressions were calculated.

RESULTS

Birth weight was negatively associated with insulin resistance (IR) and dysglycaemia (prediabetes and diabetes) in adulthood (adjusted odds ratio [AOR]: 0.76 (95% confidence interval [CI]: 0.61-0.94), OR: 0.72 (95% CI: 0.60-0.89) for IR and IR plus dysglycaemia, respectively. The AOR for IR plus dysglycaemia for males was 0.72 (95% CI: 0.51-0.99) and for females was 0.77 (95% CI: 0.60-1.01). Birth weight below 3.0 kg (Cohort 2) was associated with 1.40 (95% CI: 1.01-1.95) higher likelihood of IR plus dysglycaemia.

CONCLUSIONS

Our results demonstrate how a population of young adults experienced greater probability of IR, impaired fasting glucose, and diabetes as birth weight decreases. We report a novel finding of effect of suboptimal birth weight on metabolic alterations that belongs to developmental stages of Type 2 Diabetes in young adults born in a period of epidemiological and nutrition transition and grew in post-transition.

Epidemiology of Type 2 Diabetes in Indigenous Communities in the United States

PURPOSE OF REVIEW

The present review focuses on the epidemiology of type 2 diabetes (T2D) in Indigenous communities in the continental United States (U.S.)-including disease prevention and management-and discusses special considerations in conducting research with Indigenous communities.

RECENT FINDINGS

Previous studies have reported the disparately high prevalence of diabetes, especially T2D, among Indigenous peoples in the U.S. The high prevalence and incidence of early-onset T2D in Indigenous youth relative to that of all youth in the U.S. population pose challenges to the prevention of complications of diabetes. Behavioral, dietary, lifestyle, and genetic factors associated with T2D in Indigenous communities are often investigated. More limited is the discussion of the historical and ongoing consequences of colonization and displacement that impact the aforementioned risk factors. Future research is necessary to assess community-specific needs with respect to diabetes prevention and management across the diversity of Indigenous communities in the U.S.

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.